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Here... the details of his carb as delivered to me.

https://www.facebook.com/share/1hxFn4i5HmgFKxgv/?mibextid=WC7FNe

The only real negative about the thread is no back to back testing.

600 double pumper vs 715 3259-1

Out of the box, I would typically think a 600 makes for easier running, the 715 with effort to dial in will end up being the top performer.

Of note too:
The carb he sent me was actually super freakin cool.
It was an original 3259-1 but it had zamac welded like I've never seen before. The effort put into making the carb a double pumper with staging linkage was pretty cool.
As delivered to me, it was in VS form, but the secondary pump nozzle boss and the boss for the linkage was still present. It was clearly modified after 1970 as it used a first issue double pumper baseplate (before I got it)

I'd have bought the carb from him just to convert it back to race form.

Drew

Sure but they are still hosted on fb, I don't have the time or energy to put them on you tube ir even my own afscarbs webpage

Here is me describing the ones I recently made.
Had like 250ish sets made.

https://www.facebook.com/AirFuelSParkTech/videos/293053707146788/

Here is one explaining new vs old parts and how to address the issues of them

https://www.facebook.com/AirFuelSParkTech/videos/684225393423782/

Throttle pin heights, also shows the different ones I make and how to install them

https://www.facebook.com/AirFuelSParkTech/videos/405586851015635/

And talking about low riser and medium riser stuff

https://www.facebook.com/AirFuelSParkTech/videos/1051529845375353/


I should really just make a post here linking a lot of my useful videos.

Or I should take a day off and upload them all to my webpage

Anyway, hope these are helpful and don't come across as spam or anything like that.

Drew

Fuel log is not mine.
Linkage is.

I have a dozen videos on how to set up linkage. Not sure why it is so difficult honestly.

https://www.facebook.com/share/p/7kFnZYFAhHGS8Ah9/?mibextid=WC7FNe

I finally had a larger batch of parts made.
Got it all plated, ready to roll.

Afscarbs.com

Not a fan of the Daytona Needle and Seat at all. I typically toss them in the trash.


To OP,
I did not restore that. Looks like Mr Bunetic's work.
Here is a video where I describe how the bowls function:
https://www.facebook.com/AirFuelSParkTech/videos/520926569900660/

I sell all the parts I use individually or in kits of varying levels.  My afscarbs page also has a 6 hour video course showing me do a full tear down, blue printing, assembly, and testing of a lemans bowl carb.

Drew

Weird. I agree with Doug in regards to etoh.

The one thing I will make mention, the sticky white residue must be from something else.
My reason for thinking such:
I get carbs from all over the country. Certain areas seem prone to the residue that holds needles closed. Many areas (my own included) do not have that issue.

Etoh has become an easy thing to blame when folks don't truly know what the real problem is.


As far as 50% of all PV being bad?
I have not encountered that at all, I would suggest making sure your tester isn't the culprit. (Handheld vac pumps can often randomly bleed off)
I will say that probably more than 50% open at a different than rated point.

I'd like to have the carb rebuilt/restored

Apples and oranges Rebuilt = make it work. Restored = make it original. Vastly different costs with the same outcome.

Air Fuel Spark Prices
-4v Rebuild  $450
-4v Restoration $950

My personal favorite is to do halfway restored for survivors.
Just replate the hardware, and carefully clean the castings.

Drew, what do you think of this 735 carb? It runs great now for 2 years  and no adjustments from being built. Carb was test run after rebuild. I want your honest opinion on it. Thanks. Gary

If it runs great, you are happy with the looks, that is good enough for me.
If it is for a concours car, Bob makes some mentions that have merit.
Often "restorers" don't actually do any of the plating or chromate work. As such it is often done very uniformly in one color. This is a large part of why I learned to do plating before I started taking on customer work.  Doing everything inhouse allows for me to nitpick my work.
Other than that, I prefer to not pick apart someone else's work publicly.

I'd like to have the carb rebuilt/restored

Apples and oranges Rebuilt = make it work. Restored = make it original. Vastly different costs with the same outcome.

Air Fuel Spark Prices
-4v Rebuild  $450
-4v Restoration $950

My personal favorite is to do halfway restored for survivors.
Just replate the hardware, and carefully clean the castings.

I sent my to Holley and it came back very nice.Looks like new.

When I last spoke to the Holley guy who came to my shop, they told me they don't do that work anymore. They were asking me if I'd do it.

My view is to use someone local if available. Nothing can beat being able to bring the car to a guy's shop for a minor issue.
If no one is local I'm always happy to do the work.

If you have a stock unchanged 3259-1 it can idle with mix screws in due to massive idle feed. But it shouldn't run well.

Drew, are you saying all 3259-1 with the primary metering block #4756 came with the larger IFR?

I have an unmodified 3259-1 (Nov 66) that will idle well but idle screws only 3/4 turns out. 

Will changing to smaller IFR make for a cleaner (leaner) idle?

Yeah so about this....
Idle itself isn't a huge deal. As you mentioned, to a large extent you can control with mixture screws.
The issue is the transition to the mains.
Basically you cannot control low throttle fuel. Typically running fat isn't a huge issue. But yes you can clean it up and tinker with it via idle restriction.

What about the float bowls?  Not sure if that has anything to do with your issue but the float bowls should be at a level where just a little bit of gas leaks out of the hole once the screw is removed and the car is nudged to rock side to side.

No sight holes on the 3259 carb bowls unless you make them yourself.

Yes, true, but aren't there screws that can be removed and the car body nudged to see if gasoline comes out of the holes to indicate the level is up or alternatively if it pours out then the level is too high?  That is what I have on on my Holley 650 double pumper.  Otherwise how are the float bowls checked for proper level?  Or maybe the 715 doesn't need it?  Curious.

Dethsled, lemans bowl fuel level is set dry. If you want to check it while running, there are ways.

A vacuum gauge hooked to any full time port can give you an idea of how the carb is seeing the engine.

I do have a stock / unchanged 3259-1.  With the screws all they way in, it was barley running and running very rough.  But it was not dying. There is not a ton of difference in how it runs with the screws in or 1.5 turns out.  RPMs are low and jumping around in park.   

An explanation of why is in order.

A typical generic carb has a very "normal" idle circuit. This is why they often run fantastically on a myriad of engines.
The two common performance carbs that show a difference with this are the Cobrajet and 3259-1.
The reasons for this:
The CJ carb is designed to idle on the transfer slot. Yes it does in fact have mixture screws, but enough t slot is showing that is provides enough fuel to idle on many engines even if the mix screws are closed. Yes it will run rough.

The 3259 from 1965 has a fairly small and reasonable idle feed at .033, this works great on most engines.
The 3259-1 has an idle feed of .040 which is massive. The carb is designed to provide sufficient idle fuel for radical camshafts like the Lemans Cam.
In modern days we would just use a four corner idle carb and reduce the idle feed jets considerably. In 1966+ this was not an option, so the only way to provide more fuel was with a drastic enlargement of the idle jet.
So what happens when you pit this carb on an engine making more than 12inches of vacuum?  It tends to idle very rich and the mixture screws are often weak with adjustments. You can often close them entirely and the engine will still idle (tho badly as noted).

Typically when rebuilding a 3259-1 I do ask the customer about cam specs as I can make changes easily.

FL saac:
I am not into pushing my business on the main forum. Visit my webpage afscarbs.com and all info you want is there. Feel free to contact me via the page. Thanks

If most carbs idle with mixture screws all the way in it points toward finding fuel elsewhere not a vac leak.

I always retorque everything after a few hot/cold cycles.

If you have a stock unchanged 3259-1 it can idle with mix screws in due to massive idle feed. But it shouldn't run well.