https://www.caranddriver.com/archives/1968-tunnel-port-ford-mustang-vs-chevrolet-camaro-z-28-archived-comparison
Lots of good pictures
Great Article... ;D
I know I have that magazine. I don't remember, did the Tunnel Port toss the rods or what?
Quote from: roddster on June 09, 2018, 10:34:54 PM
I know I have that magazine. I don't remember, did the Tunnel Port toss the rods or what?
At 7,000rpm it shouldn't have. That was a four bolt C8FE Boss 302 block, or what became a Boss block and the problem with that engine was that the power band was up over 8,000 rpm to make it pull under race conditions.
In fact I think the number was 8,200+...gaboom!
Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?
Thanks
Quote from: shelbydoug on June 10, 2018, 11:04:30 AM
Quote from: roddster on June 09, 2018, 10:34:54 PM
I know I have that magazine. I don't remember, did the Tunnel Port toss the rods or what?
At 7,000rpm it shouldn't have. That was a four bolt C8FE Boss 302 block, or what became a Boss block and the problem with that engine was that the power band was up over 8,000 rpm to make it pull under race conditions.
In fact I think the number was 8,200+...gaboom!
No, not really. No engine failures on this one. This is a real Tunnel Port experimental engine:
"Well, yes, this is your regular 12.5 to one compression ratio, dry deck, tunnel port 302," allowed Ford Man still a bit defensive from the tire discussion. "How many do ya want?" Man, just the name tunnel port makes us stand at attention. It's really a simple idea but only Ford had the initiative to do it. Instead of trying to crowd the intake ports between the push-rods like everybody else, Ford just made the intake port as big as they pleased and then ran a little tube down through it for the pushrod to move inside of. A great idea. This particular 302 had a fairly tame (by race standards) camshaft and a dual-point distributor without the benefit of transistor ignition. An 8-quart road racing oil sump finished off the package."
Also as noted in the article, the Camaro was the better street car, and Mustang was the better race car.
Thanks for sharing
Quote from: fthlflyer on August 23, 2023, 11:03:34 PM
Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?
Thanks
It depends on who set up the engine which I doubt seriously could be called stock.
It may be a breather for the oil pan. At some point in the development of the Boss 302, the valve covers were using drain back tubes to the pan.
Oil sump pressures are a significant consideration on all engines and a crossover between a race and a "street" engine, that factor can be tricky or just a little controversial.
Race engines in the day were just vented to the atmosphere. Today if you can get it balanced correctly, 10-12 inches of vacuum to the pan helps seal the piston rings to the tune of something like 25hp. That requires a closed venting system which depending on the kind of racing you are doing can be difficult to balance correctly but is doable.
As far as the rev limits and the grenading tendency of the Tunnel Port engine, since I wasn't there in the day, I have to rely on the press reports and reviews of the time commenting that "the drivers" claimed there was no power in the T/P until about 8,200 rpm's at which "every single" Ford assembled engine blew.
It isn't an argument on my part, just a comment on why "the race teams" claimed the entire season was a wash.
One thing that I was looking for in the pictures that I didn't notice was the serial number stamping into the car, i.e., whether or not it showed the D engine code.
As far as I know, which again is not first hand and subject even today as controversial, how many "genuine" D T/P cars were manufactured and how many were just restamped Shelby T/A cars to comply with the rules.
I personally kind of doubt anyone would take seriously that the number produced would comply with the minimum necessary.
Thinking back on reading some of these types of review articles, I seem to remember "some" mentions, here and there, of reviewers questioning why "these street looking tires" would feel so sticky to the touch and why they all seemed to have an extra "S" in the molded in identification number?
At some point someone mentioned special test tires made by Goodyear that had soft race rubber compounds. Interesting to review now that seemingly no one talks about them anymore and certainly no one these days talks about having them "re-manufactured"?
All in all, a very interesting artifact article of the day but anyone is going to have a really tough time convincing me that both of these cars are not "factory 'ringers' ".
The quote about the Mustang Tunnel Ports by the "Ford Guy". "of sure, how many do you want" is typical smoke screen stuff of the era.
Even suggesting that either of these cars somehow came directly off of a production assembly line is just plain ludicrousness.
Quote from: roddster on June 09, 2018, 10:34:54 PMI know I have that magazine. I don't remember, did the Tunnel Port toss the rods or what?
Titus/Bucknam won out of the box at the Daytona 24 hour. They were 64 laps ahead of the second place Penske Camaro. Porsche prototypes were 1-2-3 at the finish and Titus stuck the 4th over the line Mustang right in their "ad photo".
Titus popped the first engine in race 3 - After Titus didn't win race 2 Ford had demanded that SR (SR = Shelby Racing Inc - Since mid 67 CS was no longer an independent Ford backed company but a contract race team working under Ford's dictates) not even open the engines and run them as received from Ford. If you remember this is the same stunt that Ford pulled in 1965 when they demanded SA swap their engines for Ford built ones just before the start of LeMans - head bolts failed. They took a failed TP engine apart and found it still contained casting sand. One failed on the pace lap. The onsite Ford engineer accused Titus of intentionally over reving the engine. Titus grabbed him and stuffed his head through the drivers window and pointed out the tattle tale on the tach was at 4,200....
After RPM limits by Ford that were to low to win any race and 4 failed engines Titus told CS at race 12 he would not be back for 1969. In typical CS you can't quit you're fired style Titus ended his driving for CS. Ironically Titus bought Jon Ward's Camaro AS car for the final 68 race - they swapped body parts to make it look like a Firebird but had little other prep time - the engine blew.
Interesting - Sam Posey as the test driver. He is who CS was speaking about when he made his comments about rich kids buying rides rather than coming up through the ranks.
Link to homoligation papers - https://historicdb.fia.com/car/ford-mustang-1968-gp-ii-302
Quote from: crossboss on August 24, 2023, 01:15:52 AM
Also as noted in the article, the Camaro was the better street car, and Mustang was the better race car.
This was the greatest magazine comparison test ever! The next best was the '65 Pontiac 2+2 vs. Ferrari!
But at the time, for those with automotive familiarity, it really was solely entertainment, as all concerned understood that that as was being presented was not probably representative of what was in the showroom. And although the Ford certainly appeared the more exotic 8), which was understandable when one considers that period of Ford's racing history and the products they had developed to that point; but don't think that GM showed up unprepared. After all, consider that the DZ-302 engine basically shared the same engine block (same bore and deck-height of 9.025") as that of the 327 and 350 cu. in. engines, but with a 283 crank-stroke swap for the reduced capacity. So, particularly since the article did reference how much more "street friendly" with greater lower R.P.M. torque that the GM product presented (as I recall), do you suppose they showed up with only a 302? ::)
Yeah I know, the article stated that they "checked 'em" (P & G ?), but racers have been cheating past that for decades, you think the GM engineers couldn't have figure it out! ::)
I dunno................ But remember it's just entertainment, just don't get to serious about that which we'll never know. :)
Scott.
Quote from: fthlflyer on August 23, 2023, 11:03:34 PM
Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?
Thanks
Possibly to vent the Oil Pan Sump?
I think it's typical of Ford to make only a couple of examples while GM makes thousands of them and sells them to anyone. Granted the Z28 was never a hot seller but compared to the tunnel port 302? Or even the Boss 302? The Z28 might be from GM but damn! It was a great car.
Quote from: tesgt350 on August 24, 2023, 02:39:56 PM
Quote from: fthlflyer on August 23, 2023, 11:03:34 PM
Reviving an older thread to ask a question: Does anyone know what the extra breather and tube on the Mustang's passenger's side (behind the battery and next to the solenoid) goes to?
Thanks
Possibly to vent the Oil Pan Sump?
I've seen weirder stuff then that. We will never know though exactly what the thought going on with it was. I've never seen anything quite like that and there isn't anything else that needs venting.
Mountain motor experiment maybe?
Personally I think that the cross over tube from valve cover to valve seen on the B2 T/A cars that was adapted from the NASCAR boys engine
builds is strange as well but amongst the simplest to deal with.
I should add that those things have open breathers on them and will spill on road race set ups.
The current use of a closed vent and a scrapper tank is good thinking but I don't know the issues that it has with any kind of endurance racing.
I use that set up and find mine mostly full of water with oil droplets mixing with it. It's a really yucky mess to clean out.
I agree and suspected it to be a crankcase vent of some type, but that seemed excessive with dual breathers on the valvecovers. Blown alcohol motors don't need that much venting. . .
I'm wondering if Ford didn't use something off the parts shelf from a truck or industrial application. . .
Quote from: shelbydoug on August 24, 2023, 09:27:24 PM
I should add that those things have open breathers on them and will spill on road race set ups.
The current use of a closed vent and a scrapper tank is good thinking but I don't know the issues that it has with any kind of endurance racing.
Most sanctioning bodies require the catch tanks to keep oil off the track. I wonder if that tube was added to easily add oil directly to the oil pan. I'm pretty sure dry sumps were not allowed at the time so probably not for that tank.
Quote from: 98SVT - was 06GT on August 25, 2023, 01:10:04 PM
Quote from: shelbydoug on August 24, 2023, 09:27:24 PM
I should add that those things have open breathers on them and will spill on road race set ups.
The current use of a closed vent and a scrapper tank is good thinking but I don't know the issues that it has with any kind of endurance racing.
Most sanctioning bodies require the catch tanks to keep oil off the track. I wonder if that tube was added to easily add oil directly to the oil pan. I'm pretty sure dry sumps were not allowed at the time so probably not for that tank.
I was thinking that also but here's the thing, the Mustang isn't "stock". With the numbers it put up, I'd suspect it is one of "Smokie's Specials". Whatever that tube is for kind of strongly suggests that there is no way it came off of anyone's assembly lines.
A Prosecuting Attorney, of which I am not, might even go as far as to suggest that it is PROOF. ;)
I would add, that if you were like me, and learned about these cars through publications like this, Smokey was still kind of a secret.
Bud Moore we knew something about and now that I mentioned it, who has more of a touch of making "Mountain Motors" then his shop?
I'd go with the very unlikely scenario of the Z being a 302 as well but 326/347/355's were around although kinda' expensive even for the time. They just recently have become pretty cheap to build.
You folks that have participated in magazine road tests have previously talked about the poetic license taken by your editors, out and out incompetency of some testers and flat out bribery laid on you by new sets of tires, free Taco Bell and maybe even Hurst girls? 8)
So I guess it is a "believe whatever you want thing"..."same as it ever was?"
I don't think the car with the vent tube is a race car. Because it has a nice looking windshield, wiper reservoir tank and heater hoses Going back which I don't think a race car would have.
Roy
So, if the Ford TP engines didn't make any significant power until 8000+ rpm, what ring & pinion would they have run, compared to what the Z28 used? (At the same track.)
Something crazy like 4.56? (Weren't the Camaros typically using 3.73s?)
Any lower than 4.56-ish, and me thinks the top speed would not have been bit much more than 110 mph.
(No, I didn't do an rpm to mph calculation, factoring tire height,etc. It's just a Kentucky Windage guesstimate.)
More original (unpublished) underhood Mustang photos from the shoot might certainly tell the story.
Found some research from the Group 2 FB page: Based on the '67 team Shelby car, I now strongly suspect it's an oil catch can. Maybe not the plastic bottle version seen in the photo, but the same function.
Quote from: fthlflyer on August 26, 2023, 01:02:55 AM
More original (unpublished) underhood Mustang photos from the shoot might certainly tell the story.
Found some research from the Group 2 FB page: Based on the '67 team Shelby car, I now strongly suspect it's an oil catch can. Maybe not the plastic bottle version seen in the photo, but the same function.
Great find. I remember a quote, "the best place to hide anything is in plain sight".
All regular production 68 Mustangs had oil catch cans right?
Now I'm wondering who's shop that car was built in? I don't see any give away Kar Kraft signatures and exactly how many cubic inches it had? I'm thinking 326 more then likely just for the rpm's alone. 8,000 for a 347 is kind of pushing the envelope a little too much?
The one picture recently of the Tunnel Port on the pallet in Yunick's shop with the 65 water pump and balancer on it might be a hint?
4.33's have been quoted more then a few times with B2 cars. Back in the day I'm very sure that GM muscle cars with first gear 2.20 4 speed transmissions needed 4.88's to get the 1/4 times they are now associated with. That puts them right around 110 which for a small track like Lime Rock is about right.
The 2.32 Ford doesn't need that much. The formula that I was told by serious drag racers is that the product of the rear ratio and first gear of the transmission needs to fall between 11 and 14.
My experiences tend to agree with that formula. 3.89's and 3.91's therefore are not enough. That is partially why testing a GT350 stock with a 6,000 rpm limit isn't going to even brake 14's.
I don't know what OD of the tire is though which is also a factor.
With a non-drag racing slick and a road race tire, which would be smaller in diameter, the 4.33 starts to make sense though.
All this kinda puts serious doubt on the accuracy of the writer's coverage. Seems like most of this was either not know or seriously glossed over, but remember, they just wanted to sell the magazine issue and it all looked great on the cover sitting there on the news stand.
Now it just looks like an automotive version of 'Nessie, the Locness "monster". "I saw it...didn't you?"
Lets put all of this 'speculation' to rest right now. 1-A well built Tunnel Port is no dog, and very reliable. 2-NO TP engine failed when Shelby built them, not Ford. 3-You don't need 4.56 gears. 4-I actually drove one with dual 4V carbs installed in a members 1966 Shelby GT-350. It had 3.50 gears, and drove off the line with no bogs, and had plenty of torque--actually better than a Boss 302! This TP was the 'street' version with the smaller valves. 5-I'm sure the camshaft installed was the key to all of this. 6-Both cars tested in the magazine were a 'prototype' (as was the Z/28) and not an actual T/A race car--I'm sure Smokey had his hand all over this Chevy. I'm confidant Ford's 'Experimental Garage', 'Shelby' and or 'Hollman & Moody' did on this Mustang also. 7- Most 'likely' both cars were not at a legal 5.0 litres/302 CID. IF Ford actually produced the TP for production, it would have had better street manners, and would not generate the test numbers the prototype did in the magazine.
Van and I can tell you magazine 'tests' are, well...not exactly factual. I will leave it at that.
Scott, I agree.
I can only speak for myself that we never faked numbers while I was running Motor Trend. That was my rule. We got the quickest times by having some of the top test drivers in the business.
It was generally known in the business that some of our competitors tried different methods to be the quickest.
As far as the press getting "magic screwdriver" cars to test...yes, most probably, a lot of the time. Even if it's just a really thorough prep, or a blueprinting. The paint quality and interior fitment is usually better than a comparable production car too. (Ferraris and other ultra high end cars excepted, as they already received great paint & trim 99.5% of the time.)
I have no idea what any car magazine or TV show or YouTube channel is doing, these days.
My friend lives in North Texas. He bought a new 1968 Z28 Camaro after returning from Vietnam, new in 1968. He still has it. It has headers, a roller cam, and 4.88 gears. Originally it had a 12 bolt posi. It still has that.
I drove the car a couple years ago. It's wicked fast, one of the fastest cars I have driven. It still has its original Marina Blue finish and original black interior. He doesn't care about much as he is 72 years old and does not go to many car shows.
Our HS auto shop teacher set up work experience programs with 5 of the local car dealers. Everyone of course wanted to work at Russ Davis Ford (and Gas Ronda) so he decided to hold a drawing. I got the Chevy dealer across the street working with the trans/rearend guy. The first 67 Z28 came off the transport and it was realized the UAW guy hadn't figured out how to install the Hurst shifter. I got tasked with setting it up and then the guy told me - you fixed it you test it - I took that as drive it over to school and do a few burnouts. When I got back the tune up guy grabbed it and put it on the rollers. It had almost 360 RWHP. He figured it was almost 425 at the crank. A few more than the insurance decal on the air cleaner that said 290 HP.
PS - I did spend a lot of time at Russ Davis. I was crewing on a Fuel Altered car and the driver Skip Burroughs was a wrench at Russ Davis. It was great being a fly on the wall while he and Gas were talking shop. He went on to be Gas' crew chief. The Altered had a BB Chevy and when the owner decided to go into Top Fuel the last pass for the car at Bakersfield it got a heavy dose of Hydrazine. It took them 20 minutes to clean up the track. The crank was in 3 pieces, the cam 5 even the injector manifold got tweaked when it lifted a head.
A little Hydrazine lesson for the kiddies: https://www.dragzine.com/news/flashback-friday-the-story-of-the-leathal-fuel-called-hydrazine/
Quote from: 98SVT - was 06GT on August 27, 2023, 12:00:51 PM
Our HS auto shop teacher set up work experience programs with 5 of the local car dealers. Everyone of course wanted to work at Russ Davis Ford (and Gas Ronda) so he decided to hold a drawing. I got the Chevy dealer across the street working with the trans/rearend guy. The first 67 Z28 came off the transport and it was realized the UAW guy hadn't figured out how to install the Hurst shifter. I got tasked with setting it up and then the guy told me - you fixed it you test it - I took that as drive it over to school and do a few burnouts. When I got back the tune up guy grabbed it and put it on the rollers. It had almost 360 RWHP. He figured it was almost 425 at the crank. A few more than the insurance decal on the air cleaner that said 290 HP.
PS - I did spend a lot of time at Russ Davis. I was crewing on a Fuel Altered car and the driver Skip Burroughs was a wrench at Russ Davis. It was great being a fly on the wall while he and Gas were talking shop. He went on to be Gas' crew chief. The Altered had a BB Chevy and when the owner decided to go into Top Fuel the last pass for the car at Bakersfield it got a heavy dose of Hydrazine. It took them 20 minutes to clean up the track. The crank was in 3 pieces, the cam 5 even the injector manifold got tweaked when it lifted a head.
A little Hydrazine lesson for the kiddies: https://www.dragzine.com/news/flashback-friday-the-story-of-the-leathal-fuel-called-hydrazine/
Awesome story, thanks for sharing! You guys were right in the mix of it. Unfortunately, I was born too late to see this stuff first hand...