At 6:10 in the recently posted YouTube video from Peter Klutt/Legendary on the Flip-top, there is a picture of a letter from Ray Geddes regarding using the car for testing multiple engines, including the alloy 390 and the iron 427 amongst others. One of those other engines was a 325ci small block.
I have looked around and did some searches here, but cannot find much of any info on it. Is there a good reference on that particular engine and its specs, like bore and stroke, etc.? Did it ever see use in racing? Seems I have a vague recollection that Gurney raced it...
Any tips are much appreciated!
It seems most of the references I've come across of the "325 C.I.D. engine" was that it was "under development", seemingly to be suffering from "reliability" problems, and yes it saw some actual race participation, but perhaps was most often deemed as a "secondary standard" under development, with some trepidation. :-\
Not that I have come across any specification data as produced by Ford Motor Co. or Shelby American stating what the actual bore & stroke was, or that there was only one possibility attempted, but I'd probably believe the the bore was the standard 4" coupled to a crankshaft stoke of 3.25", which actually equates to something over 326 C.I.D. closer to 327 C.I.D., but since Pontiac had a "326" and Chevy had a "327" I guessing the Ford guys just settled on the "325" moniker?
The other possibility might be with the bore at 4.030" (aka. "thirty-over) coupled to a crankshaft stroke of 3.200", which would result again into something just over 326 C.I.D.. It would come down to which issues the engineers were more concerned of, "stroke length" or the "over-bore", each bringing to the table drawbacks that could lead to problems? ???
Hopefully someone else can add to the meager information that I have, as I too find this an interesting subject! :)
Scott.
The Gurney Lotus 19 at Daytona 1965 ran that particular engine...ran as the "rabbit" to burn out the competition. Dan Gerber is also noted to have run that engine in his Peregrine Special (ex-Bob Johnson car).
Interesting info. Thanks for posting, guys! Anyone else?
Quote from: kranky on March 13, 2026, 01:31:21 PMThe Gurney Lotus 19 at Daytona 1965 ran that particular engine...ran as the "rabbit" to burn out the competition.
Yes, I had read that somewhere; and that the "325" had obviously been selected for it's performance advantage due to it's greater capacity, but also as this presented an opportunity for further testing under the conditions stipulated, and then that they didn't really expect nor really intended that it would last the duration. :-\
Scott.
Shelby American also ran 325ci cheater engines at certain tracks in the R Models and probably Group 2s as well. These were 289hipo based engines.. different from the DOHC stuff.
I believe they were run at circuits where tech was not as evasive and they put out a bunch more power and torque, obviously.
Interesting to hear that SAI did some testing of this engine in 2196. I have never seen a photograph of the car running that engine but I suppose anything is possible.
Kind regards,
Vern
I recall reading something about that engine in some book a long time ago. I can't remember the book, but I vividly recall it showing a picture of the connecting rods. I remember the picture because the rod caps were at a 45-degree angle as opposed to being flat across.
The late Wayne Richards had a block and a crankshaft from the 325 program. The main journal were a different diameter and his was set up for the "Indy 255" rods. He had no pistons and he had bought the parts from the Shelby sale when they closed down the airport facility. He had offered them to me for a possible build for my BOSS 302, however at the time I was still hunting SK parts.
John
When I was young and following the the performance of the Cobra Team, I recall a disappointing race report from a west coast race where all the usually reliable factory cars blew their engines. I believe the report said they were experimental "325" engines. Should be some documentation around.
Daytona Beach Morning Journal....Photo caption-Disgusted Gurney--Dan Gurney pokes around under the hood of his Lotus Ford after retiring from the race with a burned piston. He led all but 10 of the first 213 laps.
So there was some durability to the engine after 700 "+" miles of racing, not including practice mileage.
interestingly, i have seen factory dyno sheets for the 325 engine and the particular engine that the sheet recorded made just over 360hp and 360tq. In comparison, a full race, weber'd Cobra engine made 388hp but only 320tq
Peculiar. This 325 cu in hp/tq interplay is way off (by being the same) for a 90 degree presumably hi-perf V-8 (as opposed to say an agricultural pump-motor).
Although it could be many things, most initially look to an intake tract/ cyl head restriction, especially if/when the tq is in an 'expected ballpark'.
Not always does just increasing the engines' capacity result in more H.P.; but it does most often create greater torque numbers. This is as you are perhaps successfully transforming a smaller capacity, higher R.P.M., automotive "performance" engine, into what amounts to a larger capacity, but lower R.P.M. capability, truck or tractor engine! :o
If considering the rather conservative nature in flow capacities of the "S.B.F." inline-valve cylinder heads, this including the "C6FE" castings, and noting that this has always been a problem for allowing greater H.P. from these engines, one should realize that at some point the engine's volume capacity is going to out-run the cylinder head port flow capability (and camming) and at that point any gain in horse power at R.P.M. just isn't going to be had, even possibly reduced with the lower R.P.M.'s at which the engine might reach it's peak.
But again, torque numbers across the board (until the limited air flow kills the upper R.P.M.'s) will be up, and in a suitable application, even with less peak H.P., the greater torque can produce faster lap times. ;)
Scott.
Quote from: 68stangcjfb on March 16, 2026, 02:25:18 PMI recall reading something about that engine in some book a long time ago. I can't remember the book, but I vividly recall it showing a picture of the connecting rods. I remember the picture because the rod caps were at a 45-degree angle as opposed to being flat across.
I remember this also in a Super Ford Magazine article in the early 80's. They did an engine build and put it in a 66 GT350H.
Mike
I would like to read those articles if anyone can pinpoint the dates! Interesting that no real bore and stroke numbers come up... my guess at the different crank journal size is a welded stroker effort, which likely reduced the rod journal diameter.
As I recall, at some point, Shelby had Gurney driving "the rabbit". It was thought to have been a 325ci.
It was used to over stress the competition by being unrealistically fast and was not expected to finish the race.
Although I have seen those pictures of the offset connecting rod caps, I believe that it was small block Chevy connecting rods that were being used at least at some point in the developement.
The Boss 302 heads were intended to solve the issue of intake restrictions on the 289 heads.
The intake flow numbers as stated are really the hp restrictions with the 289 head flowing stock around 180cfm, race ported about 220.
The GT40 heads something like 240cfm and the stock B302 around 250cfm.
Current aftermarket heads for the inline valves are showing around 300cfm on the intakes and complimentary exhaust numbers.
A couple of years ago, a member here, built a 325 with AFR heads, a .528" solid lifter cam, a single Cobra intake, tri-y headers and a 715 carb and it dynoed right at 425hp.
Several involved in that build thought there was more power to be had there with better cam selection and maybe a better exhaust design that would bring it closer to 500hp?
So the thought of more power by larger displacements on the SB Ford has been kicking around for decades and you can make significantly more with modern tech.
Using old tech will result in old numbers since there is no hidden magic in the old castings.
Quote from: slither on March 27, 2026, 01:37:27 AM Interesting that no real bore and stroke numbers come up... my guess at the different crank journal size is a welded stroker effort, which likely reduced the rod journal diameter.
I'm guessing that this engine subject must have fallen under the "need to know" basis, as the available information seems limited; but with consideration, I'm betting on the 3.25" stroke crankshaft with a standard 4" bore. ;)
Now, the crankshaft makeup otherwise would be interesting! Again I'm guessing, but I doubt the 325's crankshaft was of a 289 cast piece with weld build-up to allow for the offset stroke grinding. It is probable that the otherwise intended to be 289 "raw" casting core could be turned out to the 325's dimensions or that the the casting boxes could be readily modified to permit such; but I'm more inclined to think that instead, they borrowed raw steel forgings from the "Indy 255" project and had those finish machined to the requirements? :-\
Again guessing, but I'd bet the connecting rods, at least the raw forgings, also came from the Indy 255 program?
But the documentation just doesn't seem to be available, nor does it seem the participants have ever voiced much in the way of factual information on this topic? All of which is interesting in itself! ???
Scott.
P.S. I would highly doubt that "Chevy" rods were ever actually utilized, the engineers probably had "looked" at such, just as they often studied the product of the competition in establishing what they were doing, not only in engine development, but everything else also; but I'd be concerned for my job at Ford Motor Co., if it were ever established that as an engineer I had just substituted in a set of Chevy rods and Henry Ford II ever found out! ::)
Quote from: pbf777 on March 27, 2026, 11:01:23 AMQuote from: slither on March 27, 2026, 01:37:27 AM Interesting that no real bore and stroke numbers come up... my guess at the different crank journal size is a welded stroker effort, which likely reduced the rod journal diameter.
I'm guessing that this engine subject must have fallen under the "need to know" basis, as the available information seems limited; but with consideration, I'm betting on the 3.25" stroke crankshaft with a standard 4" bore. ;)
Now, the crankshaft makeup otherwise would be interesting! Again I'm guessing, but I doubt the 325's crankshaft was of a 289 cast piece with weld build-up to allow for the offset stroke grinding. It is probable that the otherwise intended to be 289 "raw" casting core could be turned out to the 325's dimensions or that the the casting boxes could be readily modified to permit such; but I'm more inclined to think that instead, they borrowed raw steel forgings from the "Indy 255" project and had those finish machined to the requirements? :-\
Again guessing, but I'd bet the connecting rods, at least the raw forgings, also came from the Indy 255 program?
But the documentation just doesn't seem to be available, nor does it seem the participants have ever voiced much in the way of factual information on this topic? All of which is interesting in itself! ???
Scott.
P.S. I would highly doubt that "Chevy" rods were ever actually utilized, the engineers probably had "looked" at such, just as they often studied the product of the competition in establishing what they were doing, not only in engine development, but everything else also; but I'd be concerned for my job at Ford Motor Co., if it were ever established that as an engineer I had just substituted in a set of Chevy rods and Henry Ford II ever found out! ::)
Scott,
As I said regarding the actual 325 parts that Wayne Richards actually had at his shop the crank, rods were 255 Indy parts. The crank had no evidence of welding, we assumed that it had started out as a raw forging and was ground for the purpose of being used in that specific build. The block was an XE block with deck oiling similar to the tunnelport 302, however was not a "Dry Deck" block. The main bearings were not a standard size.Wayne bought the parts at the Shelby LAX sale.
John
Yea this has raised my interest in how they did this . I understand why they did it to even the 327 chevy playing field . would really like to see the actual parts used .
Yep, seems Ford was more "reactive" than "proactive" in this arena of engine packages, this example where they figured out that the Chevy guys had a 327 as of '62, and then when GM crammed their "big-block" in the Corvette in '65 (396/427), so then Henry decided the Cobra would have the "427" too! ::)
Surprisingly, the exception was when Mercury in '58, and when at the time was Fords' performance arm, just blew everybody else out of the water with the introduction of the MEL 430 cu. in. "Bulldozer" engine w/ single 4-barrel was at 350/360 H.P., 490 ft. lbs. of torque and w/ the "Super Marauder" "Tri-Power" set-up was at "400 H.P. and claimed to be 500-510 ft. lbs! :o
In comparison:
Cadillac was only at 365 cu. in. and w/ three 2-barrels was at 335 H.P.,
Chevy's new big-block "Porcupine" engine was at 348 cu.in. and with 3-duces @ 315 H.P.,
Olds was 371 cu.in. w/ the "J-2 Rocket" option was at 312 H.P.,
Pontiac was at 370 cu. in. w/ the tri-power was at 300 H.P. and w/ F.I. was 310-330 H.P.,
Chrysler who receives all of the accolades for performance in the period with the 392 cu. in. w/ dual 4-barrels was at 380 H.P, and w/ F.I. 390 H.P.; but the greatest torque was about 450 ft. lbs. w/ a single 4-barrel, but then dropped to 435 ft. lbs. with dual 4-barrels etc..
But after '58 Ford abandoned the performance efforts for the MEL and Mercury for the most part, so few know or have even heard of the "M.E.L."! :(
Scott.
P.S. O.K. I got sidetracked! ::)
"Back in the day". Long time reader of Hot Rod Magazine. You could buy a Chevy stroker right out of the magazine. But Ford stuff? Always some kind of NASA shop "could" make it for you at a price.
Quote from: pbf777 on March 27, 2026, 11:01:23 AMQuote from: slither on March 27, 2026, 01:37:27 AM Interesting that no real bore and stroke numbers come up... my guess at the different crank journal size is a welded stroker effort, which likely reduced the rod journal diameter.
I'm guessing that this engine subject must have fallen under the "need to know" basis, as the available information seems limited; but with consideration, I'm betting on the 3.25" stroke crankshaft with a standard 4" bore. ;)
Now, the crankshaft makeup otherwise would be interesting! Again I'm guessing, but I doubt the 325's crankshaft was of a 289 cast piece with weld build-up to allow for the offset stroke grinding. It is probable that the otherwise intended to be 289 "raw" casting core could be turned out to the 325's dimensions or that the the casting boxes could be readily modified to permit such; but I'm more inclined to think that instead, they borrowed raw steel forgings from the "Indy 255" project and had those finish machined to the requirements? :-\
Again guessing, but I'd bet the connecting rods, at least the raw forgings, also came from the Indy 255 program?
But the documentation just doesn't seem to be available, nor does it seem the participants have ever voiced much in the way of factual information on this topic? All of which is interesting in itself! ???
Scott. ::)
Seems odd that the info has never really seen the light of day...
There was an article published. I believe in late 70s to early 80s. I also remember seeing the rod with the angled cap on it.But couldn't swear that that was for a ford or what Engine it was for. If memory serves me, which is questionable, I think the article said that Ford put three of the engines into cars for testing. I remember after reading it that I wondered if a guy at work had one of those engines in a car he had because it ran a lot stronger than it should have and it was totally stock,As far as he or anybody else knew. My Mustang had a built engine, and we would run basically head to head. So that made me wonder if he might have one of those cars that got out of ford. There's a good chance that I still have the magazine or engine annual that had a write up on that engine.But with close 5 thousand magazines, it's really going to be hard to ever locate it. Here's a picture of about 4000 magazines. And a few dozen catalogs and other odds and ends of ephemera, for those that probably don't believe i've got that many. There are hundreds more in each of the man caves,one in the house And one in the garage. I will keep my eye open for the article, As there are some things, I need to look up and some of the magazines.
Part of the possible engine problems
Could have been the angled caps because bolts are not made for side strength.They are made to be stretched and have strength in that plane.So they might have given away due to the angle of the rod bolts.
Roy
offset grinding a 289 stock crank to a 3.230 stroke makes the big end of the rod really small. this would not ad reliabilty in a race engine . but would reduce friction and increase hp (for a short time) I do not see any 255 indy parts that would interchange with this project .
Requires a rod with a
1.77 bore
Quote from: gt350shelb on March 29, 2026, 11:16:20 AMoffset grinding a 289 stock crank to a 3.230 stroke makes the big end of the rod really small. this would not ad reliabilty in a race engine . but would reduce friction and increase hp (for a short time) I do not see any 255 indy parts that would interchange with this project .
Requires a rod with a
1.77 bore
There are many things that are said on the Internet that because they are not actually said in a conversational environment don't come off with the respect intended, so please understand that what I am saying is from the highest mutual respect.
In the parts that Wayne had from Shelby the crankshaft was an XE forging, (I'm aware of the difference between a forging and a casting) the rods were Indy 255 rods and the block was an XE block. Other than that I can not tell you anything else. I know that from what I have seen and touched in my FoMoCo adventures over the years not everything is cataloged.
Quote from: shelbydoug on March 27, 2026, 08:36:44 AMAs I recall, at some point, Shelby had Gurney driving "the rabbit". It was thought to have been a 325ci.
The Lotus 19B and/or 19J. Gurney had been running the Arcerio Brothers Lotus 19 with an aluminum Buick (Traco?). John Klug of Pacesetter homes sponsored the one off 19B designed by Len Terry for Lotus with a 289. All the Lotus 19s had reliability problems - mainly gearbox. The famous Gurney win by stopping his failed car just short of the finish line until time ran out was the Arciero car not the 19B. Gurney's All American Racers partnered with CS for 2 1965 races in the much modified 19B listed as a 19J running Shelby colors - and undoubtably a SA supplied engine. It had 2 DNFs both engine failure. The car was later found by Wayne Lyndon under a pile of used tires at Caldwell Tire company in Pasadena. He was a fireman and owned part of a model train store. He opened a store in Sacramento and that's when Gordon Gimbal bought the car from him for his wife Nancy to race. It was well known here in CA having been restored to it's Pacesetter paint scheme. The Arciero 19 continued racing with a different driver and Chevy. These little V8 Sport Racers are considered to be the genesis of the CanAm cars.
[q
[/quote]
There are many things that are said on the Internet that because they are not actually said in a conversational environment don't come off with the respect intended, so please understand that what I am saying is from the highest mutual respect.
In the parts that Wayne had from Shelby the crankshaft was an XE forging, (I'm aware of the difference between a forging and a casting) the rods were Indy 255 rods and the block was an XE block. Other than that I can not tell you anything else. I know that from what I have seen and touched in my FoMoCo adventures over the years not everything is cataloged.
[/quote]
totally agree with XE parts anything is possible back then
I must agree often Ford is late to the party. But the 427 FE R code (dual quad) was in 1963 Galaxies. The Flip Top Cobra was built in 1964 as a big block test bed. Arnig was already developing the coil spring chassis. GMs 396 came out in 1965 and wasn't a 427 until 1966. Then Ford did copy it's porcupine valve layout for the Cleveland.
Quote from: gt350shelb on March 29, 2026, 11:16:20 AM. . . . . offset grinding a 289 stock crank to a 3.230 stroke makes the big end of the rod really small. this would not ad reliabilty in a race engine . . . . .
I believe you looking at this from the perspective of us, as the end-user in the performance aftermarket, this being post O.E.M. production. But a an O.E.M., they had access to the "raw" castings/forgings which could accommodate reasonable stroke adjustments without the "need" to be of a smaller journal diameter. :)
Quote from: TA Coupe on March 29, 2026, 02:56:31 AMThere was an article published. I believe in late 70s to early 80s. I also remember seeing the rod with the angled cap on it.But couldn't swear that that was for a ford or what Engine it was for.
Yeah, I'm in the same boat; kinda remember, but I just couldn't bet a lot on it! :-\ Besides, it was a "magazine article", and I'm not sure I'd bet my life on anything printed there any more than that on the inter-net today! ::)
QuotePart of the possible engine problems could have been the angled caps because bolts are not made for side strength.They are made to be stretched and have strength in that plane.So they might have given away due to the angle of the rod bolts.
The "angled cap" or "parting-line" connecting rod isn't really terribly unique, often practiced on smaller bore engines or particularly heavy duty industrial examples where they might be quite under-square with "generously sized" journals and "meaty" rods are utilized, this where the rod big end wouldn't fit down the bore otherwise. ;)
Now, the "angled parting line" rod, if was as utilized in the "325", doesn't really make sense on the 4.00" bore, after all we're familiar with the BOSS 302 "TA" rod and as meaty as that thing is, it drops-in with the standard horizontal parting line; but if in the process of looking for a better/meatier example than that of the 289, preferably something that was already in the pipe-line, and the rod had been borrowed from the 255 cu. in. "Indy" project, well the 255's bore was only 3.76"!
Hmm . . . . . :-\
I would agree that the bolt being placed in even a scenario of a partial "shear" probably isn't really a positive, but the idea is that the heft and draw on the fastener for the tightening torque is to be far greater than the shear influence.
And this is just another example of one of those "compromises" the the engineers must wrestle with in creating the total package of an engine. :)
Scott.
Quote from: 98SVT - was 06GT on March 29, 2026, 07:34:24 PMI must agree often Ford is late to the party. But the 427 FE R code (dual quad) was in 1963 Galaxies. The Flip Top Cobra was built in 1964 as a big block test bed.
And that is the very car that was supposed to have tested the 325ci engine... 20 over with 3.2" stroke would yield a 324.92ci. That said, it seems that would be a stretch for a 289 crank, which begs the question if Ford was working on some slightly larger stroke cranks for the racing program. It's not much of a stretch to get to a "yes" there!
I doubt it's necessary to try and make the "325" moniker a perfect physical dimensional match in the bore & stroke guessing game as manufactures have been assigning implications of such in their labeling for decades. ;)
As an example: In 1963 with the introduction of the Pontiac "326" cu. in V8 it was actually "336" cu. in.; but apparently due to GM's capacity restrictions "labeling" it as being something under "330" cu. in. meant that it would be applicable for installations in more chassis.
And then the other story is that since GM's "flagship" vehicle, the Corvette, would have Chevy's 327 cu. in. engine example, Pontiac was "informed" that the "336" just wasn't going to fly! ::)
For 1964 the "326" actually became something closer to just that! :)
Scott.
Interesting tidbit, pb!
The 1965 Shelby De Tomaso P70 designed by Peter Brock was scheduled to also be powered by the 325 engine with a future engine size increase to a 7-liter engine as of early August 1965.
It really would be interesting to know what it seems may have been the "reliability" problems that the "325" had been experiencing; that as of the past few decades the 3.4" stroker-crank packages have proven to be really "no problem". :-\
And of course, even if it were accurate in the notion that there 'were' reliability problems, we also don't know if such was actually related to the engines capacity increase or whether caused by some other deviation from the 289 package? ???
This thread seems to be one with more questions than answers; but at least someone is asking! :-[
Scott.
Quote from: pbf777 on April 06, 2026, 11:38:17 AM..... that there 'were' reliability problems, we also don't know if such was actually related to the engines capacity increase or whether caused by some other deviation....
Let's not forget the Ford edict that CS swap his engines in the 65 GT40s for ones built by Ford the night before LeMans - ALL failed. The Tunnel Port is another one. Shelby won the Daytona 24 hour 4th overall behind 3 prototype Porsches and 64 laps ahead of the 2nd place TA car. Then Ford required the engines be run as received and not even opened to check things like valve lash - multiple DNFs were the result. Titus had one of those fail on the pace lap. The tattle tale was at 4,200 RPM.
Ford has a weird internal culture/mindset where they hire outside help to get the job done but then go out of their way to make it appear their inhouse guys did it and are the best in the world and know what they are doing.
Here's a little insight - https://www.youtube.com/watch?v=paEQCZxclPQ
Quote from: 98SVT - was 06GT on April 06, 2026, 01:08:28 PMFord has a weird internal culture/mindset where they hire outside help to get the job done but then go out of their way to make it appear their in house guys did it and are the best in the world and know what they are doing.
It's not really "weird", it's just the bureaucratic mindset of incapable individuals, justifying the curb-stops out in the parking lot with their names on them! ::)
Scott.
Quote from: 98SVT - was 06GT on April 06, 2026, 01:08:28 PMThe Tunnel Port is another one. Shelby won the Daytona 24 hour 4th overall behind 3 prototype Porsches and 64 laps ahead of the 2nd place TA car. Then Ford required the engines be run as received and . . . . multiple DNFs were the result.
And yes, the "Tunnel-Port" engine 'is' another one, that although there is a greater sum of information on, still leaves one wondering just what actually happened? ???
Scott.
Quote from: pbf777 on April 06, 2026, 02:50:38 PMQuote from: 98SVT - was 06GT on April 06, 2026, 01:08:28 PMThe Tunnel Port is another one. Shelby won the Daytona 24 hour 4th overall behind 3 prototype Porsches and 64 laps ahead of the 2nd place TA car. Then Ford required the engines be run as received and . . . . multiple DNFs were the result.
And yes, the "Tunnel-Port" engine 'is' another one, that although there is a greater sum of information on, still leaves one wondering just what actually happened? ???
Scott.
Street car engine builders using out of the bin parts for race engines. The 65 LeMans failure was due to head bolts failing. Grade 8 would have lasted and Ford would have won a year earlier. SA tore down one of the first TP failures and found casting sand still in the engine.
Quote from: 98SVT - was 06GT on April 06, 2026, 03:00:54 PMThe 65 LeMans failure was due to head bolts failing.
I have a bad habit of not accepting statements at their face value, and this presents as possibly a good example of the difficulty, for anyone at this point in time, of being able to determine the "actual" cause(s) in the failures of this era. As unless one actually has access to evidence and/or technical inspections/testing as done by true experts on the subject matter, the rest of even the in period testimony or remembrances in later periods, just ends up as generalized perspectives provided by those whom really probably shouldn't comment in absolutes. :)
To explore further, here, "head bolt failure"? Well, I'm guessing the bolts didn't just unexpectedly snap-off and cylinder heads just fell onto the ground? So probably the problem was "head gasket failure" which led to overheating, which put the car(s) out of contention, which was then attributed to "bolt failure"? The perspective issue here might be that generally in this sort of engine configuration and with "proper" type of gasket, surface preparation, etc., if the clamp load can be maintained on the gasket, it most likely isn't going anywhere, and it's generally accepted that the weakest link are the fasteners and that "lifting" of the cylinder head is often the accepted cause of a "blown head gasket" (but not always ;) ). Attempting to address this issue is what has made ARP Fasteners who they are today!
So, were the head bolts truly "defective"? Or rather as intended, just "not capable" by design? ???
And then, perhaps the bolts "were" capable, under the intended application and environmental conditions, but there was just to much cylinder pressure (say, ignition timing and/or running compression) and/or heat (was the cooling system capable?) for the octane capability of the fuel, and if not, did a potential detonation scenario lead to the chain of events that became addressed as "head bolt failure"? ::)
B.T.W. The Ford O.E.M. head bolts as utilized here are of a grade greater than "8", though not having been graded as such, it's generally accepted as say a Grade "9". If you take a set of 1/2" x 13t grade 8 fasteners of the same lengths as the O.E.M. Ford units, pull them to the 95-105 ft. lbs. torque specification, if you have any "feel" for such (if they just don't snap-off! :o ) you'll know their not as capable. ;)
Scott.
Quote from: 98SVT - was 06GT on April 06, 2026, 03:00:54 PMSA tore down one of the first TP failures and found casting sand still in the engine.
Not disputing this statement, but I "think", I remember that it was after one of these engine failures, that upon tear-down at S.A., it was blasting media that was found in the oil pan and it was determined that it was residue as from the standard cleaning process adopted at S.A. of the oil pans, which was abruptly changed thereafter to not. :-\
Now I said, I only sorta remember, something like that, so it's O.K. to blast me out of the water, and tell the "correct" story! ::)
Scott.
Quote from: pbf777 on April 06, 2026, 05:09:54 PMQuote from: 98SVT - was 06GT on April 06, 2026, 03:00:54 PMThe 65 LeMans failure was due to head bolts failing.
I have a bad habit of not accepting statements at their face value,
CS interview stated - Head bolts streched.
Quote from: pbf777 on April 06, 2026, 05:23:40 PMQuote from: 98SVT - was 06GT on April 06, 2026, 03:00:54 PMSA tore down one of the first TP failures and found casting sand still in the engine.
Not disputing this statement, but I "think", I remember that it was after one of these engine failures, that upon tear-down at S.A., it was blasting media that was found in the oil pan and it was determined that it was residue as from the standard cleaning process adopted at S.A. of the oil pans, which was abruptly changed thereafter to not. :-\
Now I said, I only sorta remember, something like that, so it's O.K. to blast me out of the water, and tell the "correct" story! ::)
Scott.
Engine torn down was one sent from Ford. Titus' kid told me it was casting sand. He also told me that a Ford engineer accused his dad of over revving an engine on the pace lap and causing a failure. Titus grabbed the guy by the neck and shoved his head in the car to see the tach at 4,200.
Quote from: 98SVT - was 06GT on April 06, 2026, 07:03:56 PMCS interview stated - Head bolts stretched.
Carroll Shelby's statement isn't to be ignored and may be quite legitimate. But the question is how accurate and truly revealing is it and how do 'you' interpret it? Not to beg the question, and probably why I'll never be chosen to sit as a juror, at least not by those whom shoulder the burden of "proof", but this statement doesn't address any of the possibilities or questions I posed; rather it plays right into the scenario that I find makes for question. ::)
Even we we choose to accept it at face value, is it that the head bolts were "defective" and just stretched, this after being put into operational service? Or was this due to "improper installation" (aka. over-torqued) and stretched? Or rather, an indication of "inadequate engineering execution" in the sum of and/or size of, aka., just not capable; and/or that of the supporting structure that they engage proved insufficient in rigidity?
Then, maybe the overall failure was just simply attributed to the known fact that the head bolts stretch (spring) in the operational functioning of the engine, just a little, this within the "elastic" limits of the fastener and isn't generally a problem until it becomes excessive (eg. due to detonation) and then the necessary clamping load requirements for gasket retention is potential lost, if only momentarily. But this would rarely enter into the "plastic" range of the fastener where there would be retained elongation that could actually be physically measurable and warrant the label of as being "stretched". And often, even if the bolt had stretched, it perhaps was inevitable and the true "fault" may prove due to the actions of other events involving other componentry encompassing the engineering endeavor as a hole? :-\
The sum of these considerations or any others, prove as unanswered in the simple statement, because as stated previously, it is generally just accepted that in most instances if the head gasket blows it's because the clamping load which holds it in place was lost, and this in simplistic views this is solely the responsibility of the fastener; but in reality such events generally involve more than one aspect, as rarely is a failure the result of a singular action. ;)
Besides, wasn't in some interview where C.S. was being asked something technical about the cars and his response was something amounting to: Hell, I don't work on the cars, I hire other people to do that! :o
But in the end, I surely don't know . . . . . but I wonder . . . . . .? :)
Scott.
Quote from: pbf777 on April 07, 2026, 01:24:39 PMBesides, wasn't in some interview where C.S. was being asked something technical about the cars and his response was something amounting to: Hell, I don't work on the cars, I hire other people to that! :o
But in the end, I surely don't know . . . . . but I wonder . . . . . .? :)
True CS was no wrench - or engineer. But he did put a winning team of wrenches together that also knew the ins and outs of extracting the max out of engines and that street car production parts would not get the job done. Chuck Beck (Porsche 550 Spyder kit, etc) was a fabricator at SA. The GT40 originally had a small gel cell aircraft battery. Ford demanded that the whole area be rebuilt and modified to accept a big Motorcraft wet cell battery. I wonder how many of those died from the added vibrations and G forces in the racing environment.
In the end none of us will truly know. Unlike Enzo who enshrined his failed parts so his engineers didn't make the same mistake twice Ford's corporate structure assured that problems were swept under the carpet and the blame moved down the employee chain to protect your job.
Enzo's "room of mistakes"
One of the engines that was swapped out at Le Mans in '65 was the experimental 325ci engine in the Rob Walker GT40 driven by Bondurant and Maglioli. Bob mentioned later that he really liked the 325 as it made a lot of torque coming out of the slower corners, much better than a 289. Alas his GT40 was a DNF with the swapped 289.
https://www.facebook.com/photo/?fbid=1490916185915959&set=pcb.3961733477461191
Found this article about the 325 cid engine from Tasca Ford. It goes into pretty good detail about the specs of the build. It's possible Ford, Tasca and Shelby were working together on it to some extent.
Quote from: CSX2601 on April 19, 2026, 06:04:06 PMthe experimental 325ci engine in the Rob Walker GT40 driven by Bondurant and Maglioli. Bob mentioned later that he really liked the 325 as it made a lot of torque coming out of the slower corners
The increase in torque would happen with the longer stroke - 3.25".
Which BTW could make it the same bore/stroke as the 327 Chevy 4"x3.25" 326.7
What's the story on the Mustang in the central pictures? Was it mods they offered? Single euro style stripe, pony interior, GT350ish side scoops, Hurst mag wheels, Tbird taillights.
Quote from: jimhyc on April 19, 2026, 09:18:08 PMFound this article about the 325 cid engine from Tasca Ford.
Great find! ;D
But, I wonder if rather this article might be describing "a" 325 cid engine (Tasca's version) and not necessarily "the" 325 being discussed here? :-\
Anyone know what version of Holley carburetors the "540 C.F.M." units might be? R1847's maybe? 1848's were rated at "465 C.F.M."; 1849's were rated at "550 C.F.M." (smaller venturi size) maybe a "recalibration" due to . . . . . . ? Just some numbers to keep others confused? ???
Scott.
The car in the middle of all the photos was known as the 1965 Tasca 505 Mustang, I never knew what powered this Mustang or what the 505 was designated for but we all do now. There was an article in one of the old Shelby Americans, one of Cobrasation articles where Kopec/ Pardee spoke to the lead Tasca 1965 GT350 salesman, his name was something like Tony Gonsolves? if I remember correctly. I don't have that issue in front of me. Anyways, it was a fantastic article on the what it was like to give demo rides and how to sell a 1965 GT350 back when they were new. I read that article over and over again, so much I spoke to Howard about him, turns out Tony had lied about some of the stories he had told in the article. In the article, he mentioned about racing the 505 while he was in a 65 GT350 on the local turnpike/ freeway and how the 505 would always pull away from him. I do have a 65 GT350 spec sheet with the Tasca stamp and Tony's name, so I at least know he did work there. Not sure what ever happened to the 505.
Quote from: pbf777 on April 20, 2026, 11:33:00 AMBut, I wonder if rather this article might be describing "a" 325 cid engine (Tasca's version) and not necessarily "the" 325 being discussed here?
It appears that Tasca is using the Ford specs for their 505 project. Somehow we'd need to find their crankshaft source. Was it a Ford experimental part or a local crank maker?
Tasca was known for creating his own car and engine mods - not always out of the Ford bin.
The letter is unsigned - did it not go out to potential customers (when Ford scrapped the 325 idea)?
Quote from: 98SVT - was 06GT on April 20, 2026, 12:32:18 PMIt appears that Tasca is using the Ford specs for their 505 project.
In the description, the use of "exact" and "also" prostitutes the intent. :(
QuoteSomehow we'd need to find their crankshaft source. Was it a Ford experimental part or a local crank maker?
I'm guessing but perhaps: https://www.facebook.com/groups/434525774318705/posts/449082129529736/
Scott.
Quote from: pbf777 on April 20, 2026, 02:07:58 PMQuote from: 98SVT - was 06GT on April 20, 2026, 12:32:18 PMIt appears that Tasca is using the Ford specs for their 505 project.
In the description, the use of "exact" and "also" prostitutes the intent. :(
QuoteSomehow we'd need to find their crankshaft source. Was it a Ford experimental part or a local crank maker?
I'm guessing but perhaps:
"exact blueprint specs from Ford" Only tells us they used Ford engineering data.
Tasca has always been focused on drag racing with little involvement in road and/or endurance racing. With today's metallurgy and engineering 505hp out of a small block is a cake walk back in the 60s it would have been a hand grenade that the builder kept the pin.
With there being "no substitute for cubic inches" I can see the genesis of the engine being why are we giving up 38 cubic inches to the Vettes? From there a welded crank as a proof of concept. Then Ford creates the crank forging/casting(?) and sends some to SA, Tasca and probably HM for them to play with. We don't know what the failures were but I suspect rod length v rpm played into it. As noted they were spinning it at 8,000 rpm. While the longer rod in the 327 was probably held below that speed. (note: 8-9 grand through the lights was fairly common for 60s pro drag cars but not road race cars that were expected last lap after lap)
Crankshaft Co. while across the country from Tasca was well known and respected here in SoCal and probably used by SA for some of their crank work.
Can you imagine driving the Lotus 19B with 505 horse? Less than 2.5 pounds per pony. A 500 horse Mustang today has about 8 pounds per horse (and street tires that surpass 60s race tires).
I remember "Hank the Crank" rather then the "Crankshaft Company", but automobile manufacturers being what they are, don't use the term "theft of design", they refer to it as "modelling".
There is likely nothing that was not available to "qualified racers" through Ford's "XE Indy Program". Just not available to you and me whereas even as an 18 year old I could walk into a Chevy dealers parts department and buy a race ready engine immediately.
I do remember 327 four bolt short blocks being $325.
Supposedly "the Deuce" was disappointed that there was no increase in Ford vehicle sales considering the vast sum that he personally had invested in racing. However, maybe if these parts were available to an 18 year old like me, even though I was still wearing sneakers, the investment might have paid off?
From what I personally have seen with XE parts, they were second to none and frankly still are. Which is why some of us still hunt for them.
Unlike those forgings, my Joe Nameth white leather Pumas have not survived the years. Just as well. I likely would just be embarrassing my wife and sons by wearing those? Not to speak of the white Levis?
I do remember having a Joe Namath "foo Manchu" for about a week. I got disgusted in that most never noticed it because it was so light colored.
I'll stick with XE parts. Those still have real value.
Wasn't the crank in the GT40's an XE forging and mated to a four bolt block? The Boss 302 used initially a C8FE block of which the original casting was out of the "Indy Program".
Quote from: shelbydoug on April 20, 2026, 04:38:36 PMI remember "Hank the Crank" rather then the "Crankshaft Company",
There is likely nothing that was not available to "qualified racers" through Ford's "XE Indy Program". Just not available to you and me whereas even as an 18 year old I could walk into a Chevy dealers parts department and buy a race ready engine immediately.
Crankshaft Co. was the "discount" place. Hank the Crank had the name and seemed to use that to charge more money.
It's always been cheaper to make horsepower and race a Chevy instead of a Ford. Take a look at GM crate engines today compared to the Motorsport catalog. GM's sales to anyone did a few things - increased the sale of parts lowering the price per item. Got Joe Cool to buy that new car on Monday knowing he could race it Sunday with the same parts he saw winning last week. As the typical Ford guys we were happy to see the Fords win but knew they were doing it with backdoor parts that if they were available to us Levi & Tshirt racers we couldn't afford them. It was Ford's pricing and corporate structure that prohibited them from profiting from racing nothing else.
The guy up the street from me was a strong local Chevy racer with a regular car repair shop. He and a partner bought a 69 COPO Camaro. He said specializing in Chevy offered him a chance at more customers and profits than Ford. His shop was the LA area go to place for Chevy building/tuning. You always knew when Grumpy Jenkins was in town - his shop doors were closed lest anyone get a view of the Grump's secrets.
Back when I was racing in the late 60's, I used to get upset when I would walk into the local Chevrolet dealer's parts department and see a L88 long block selling for not much more than what I was paying for a HiPo 289 short block. Still get steamed thinking about it!
"Hank The Crank" didn't come about until the early '70's and apparently founder Henry Benchtloff worked for the Crankshaft Company in Los Angeles before he hung out his own shingle. :)
The ol' '70 Shelby had a Ford steel 427 crank that had been reworked by H.T.C.; welded, stroked and had the extra center counter-weight added. 8)
Scott.
Quote from: 98SVT - was 06GT on April 20, 2026, 08:08:56 PMQuote from: shelbydoug on April 20, 2026, 04:38:36 PMI remember "Hank the Crank" rather then the "Crankshaft Company",
There is likely nothing that was not available to "qualified racers" through Ford's "XE Indy Program". Just not available to you and me whereas even as an 18 year old I could walk into a Chevy dealers parts department and buy a race ready engine immediately.
Crankshaft Co. was the "discount" place. Hank the Crank had the name and seemed to use that to charge more money.
It's always been cheaper to make horsepower and race a Chevy instead of a Ford. Take a look at GM crate engines today compared to the Motorsport catalog.
My father was of the same opinion and told me so once a long long time ago though he was mostly a dyed in the wool Ford guy.
Thanks, Jim, that's great info! Much appreciated!
Calculating displacement using a 3/8" increase in stroke puts it at 5 thou less than a 3.25" stroker crank, or right at at 3.245". With a bone-stock bore of 4", we are looking at 326.22ci displacement with the 3.245" stroke, unless I failed in my calculations. I would have thought that they would have called it a 327ci under those circumstances, in order to compete head to head with the 327ci displacement bowties... thoughts?
The crankshafts utilized were highly modified C1TE 8 counterweight raw forgings, originally intended for a 292 Y-block truck application.
They were initially obtained by Ak Miller in his capacity as FoMoCo's Performance Advisor for 'outlaw' use in his 'Cobra Kit Special'. This was a Tojeiro/AC chassis'd, fiberglass bodied roadster for the 1964 Pike's Peak Hillclimb event. The intent was showcasing the efficacy of Cobra Kits in which Ak worked in close collaboration w SAI in developing and promoting on behalf of Ford.
In getting this going, Ak worked w longtime associate Alex Alexander, owner of Crank Shaft Company (CSC). Hank Bechtloff was an employee of CSC who is credited with doing the work.
Specifically:
-the 292 inherently shares the same cylinder bore spacing as a 289 (which is also why Gurney utilized Y block OEM shaft rockers on his later Gurney-Weslake cylinder heads);
-the C1TE required significant machine work on shortening the snout, thinning and re-contouring the forward counter weight and forward main journal, and significant modification/creation of the aft flange which the raw forging fortuitously allowed. This got it into the 289 block;
-once in, the (originally intended) 3.300 stroke was reduced to 3.25, and crankpin diameter reduced from (intended) 2.188 to 2.00 (a 289 crankpin is 2.123);
-CSC and Ak utilized a CSC I-beam/capscrew connecting rod (itself an impressive piece circa 1964). Connecting rod inserts from a 215 Olds application were utilized;
-from this CSC did have a short term marketing of this set up with the capability of up to a 3.45 stroke through offset grinding;
-it was not a secret, nor was a seller;
-it was covered in the aftermarket press with little fanfare, the Oct 1964 Hot Rod mag being notable;
-the Shelby American engine shop of this period was comprised largely of CS hires from Culver City, Gardena, and Whittier. These were the guys who built the then-terrifying engines for the 289s: roadsters, FIA, USRRC, Dragonsnakes and Daytonas;
-the 325 project was concurrent with SAI's reception of the GT40 program from FAV and SAI's initial push to go 289/wet sump with their on-property staff;
-this was prior to any Dearborn involvement or any SK,XE,C6FE,C7FE parts for the 289;
-this was all to change after LeMans 1965 through classic 'mission creep' as Dearborn took increasing control to the point where they were shipping sealed E&F and HM FE engines, through the later TP302 debacle, etc. All at the expense of the SAI engine team, many of whom re-migrated to Culver City and the remaining SAI engine shop was basically reduced to sell formulaic 'R-model' engines via catalog. (It probably wasn't until the 1969 Revson 'Shelby' B302 program utilizing Falconer & Dunn that local engines were used;
-couple loose ends: CSC was a super top tier operation, this was no Speed—O-Motive nor later PAW, and yes Hank later split off circa 1971...still a legend.
This entire topic is classic Ak Miller, a major player, whose seminal involvement w early SAI is largely lost to history and not a part of the SAAC narrative.
(pics attached)
Beautiful looking crank shaft! One thing to watch out for when stroking a 289 bock is that the cylinders are a bit shorter on the bottom end. So not as easy to get away with as on the later blocks that had longer cylinders. I enhanced the crankshafts picture so that you can read some of the numbers a little bit better.
Roy
Quote from: slither on April 21, 2026, 11:21:10 PMI would have thought that they would have called it a 327ci under those circumstances, in order to compete head to head with the 327ci displacement bowties... thoughts? [/font][/size]
NEVER - it implies you are late to the party and merely following the competition. Beating them with a smaller engine however is advertising gold. Engine sizes were always rounded off to something the engineers were happy with and the ad guys thought would sound good. You couldn't even trust hp ratings. The insurance went up greatly once you got over 300 horse.
Quote from: camp upshur on April 22, 2026, 06:02:47 AMThey were initially obtained by Ak Miller in his capacity as FoMoCo's Performance Advisor
This entire topic is classic Ak Miller, a major player, whose seminal involvement w early SAI is largely lost to history and not a part of the SAAC narrative.
AK was a legend. Lakes racer in the 30s. Past Pres SCTA. Many Pikes Peak wins. Drag racer - 1st VP of NHRA. We only saw in Hot Rod a small portion of his back room Ford work that got buried in their corporate world. I think his last involvement with Ford was his 70 Pikes Peak class win in a "stock" 351C Mustang. He did work on Pantera and had a great turbo system for them.
In reality he was to Ford in this time what Smokey Yunick was to Chevrolet.
His shop is still open but I don't know who's running it today.
From camp upshur - the Shelby American engine shop of this period was comprised largely of CS hires from Culver City, Gardena, and Whittier. These were the guys who built the then-terrifying engines for the 289s: roadsters, FIA, USRRC, Dragonsnakes and Daytonas
RE: Culver City - that was the real center of racing in SoCal from the 1920s thru the 60s. https://www.culvercityhistoricalsociety.org/the-historic-culver-city-racing-scene/
Wow, camp, this is the holy grail of SAI 325ci engine info!! Thanks for taking time to post. I enjoyed reading it!
Much appreciated.
camp upshur, how have you come by all of your information? Sounds like maybe you were an insider somewhere back in the day?
Roy