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Posted by: Txgasser Dec 1 2008, 09:06 AM

Has anyone in the group ever mounted a 4 bbl carb on a 914-1.8 or 2.0 before? If so how did it work out?

Thanks,
Johnny!

Posted by: Vacca Rabite Dec 1 2008, 09:24 AM

Everyone using twin webers has 4bbl carbs....

I know, not what you meant.

You will have the same basic drawback of any progressive carb on our engine. The intake runners are too long and the gas vapors re-solidify before they can be burned.

Zach

Posted by: davep Dec 1 2008, 10:13 AM

QUOTE(Txgasser @ Dec 1 2008, 07:06 AM)

Posted by: Jake Raby Dec 1 2008, 12:54 PM

The long runners and a center mounted carb are horrible to tune on a 4 cyloinder engine. The fuel builds droplets as it falls from suspension in the super long runners.. It always runs rich.

Posted by: Txgasser Dec 1 2008, 01:15 PM

So much for that idea!
I guess i'll stick with 40's or 44's!

Thanks,
Johnny!

Posted by: Vacca Rabite Dec 1 2008, 01:57 PM

Go with dual 40s. You can make 44s work (I am) but they are really a bit big for a 2.0 - even a hot one.

Zach

Posted by: marks914 Dec 1 2008, 02:38 PM

Holley has some 390 CFM carbs with pretty small primaries

mark

Posted by: Dr Evil Dec 1 2008, 09:13 PM

I am using a holley 390 on my 3.1L /6 corvair motor. It is workable, but it would be pretty big for a 2.0 from what I have seen.

Posted by: Brett W Dec 2 2008, 11:38 AM

There is a guy here in town that has built a manifold for a holley four barrel on a 3.0 Six. I have never talked to the guy but his kid called me up and was telling me about it. How he never could get it to run right with the CIS and that his daddy works for NASA and can get anything made. So apparently he has made this manifold.

I told him his dad was a dumbass and didn't understand the physics of the problem he is creating. Oh well. Stupid people will learn.

Posted by: Txgasser Dec 2 2008, 11:41 AM

Morning, Brett!
It was an idea, but I think i'm going to stick with a pair of 40's!

Thanks,
Johnny!

QUOTE(Brett W @ Dec 2 2008, 09:38 AM)

Posted by: Brett W Dec 2 2008, 12:18 PM

Ideas won't screw you. Its acting on that idea that will get you in trouble. Good luck with your project.

Posted by: futuresoptions Dec 2 2008, 01:31 PM

Took the CIS off my 911 and did this.... drove it around with no problems... If I was going to try this on a 914, I would probably go with a 2bbl and jet it down...


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Posted by: Brett W Dec 2 2008, 01:56 PM

And I have walked around in the rain without an umbrella. But Why? CIS ain't rocket science. It is simple mechanical FI with no complicated parts. It is much better than any center mount carb.

The factory designed the intake manifold to flow air only. It was not designed to maintain fuel in suspension. You absolutely lost performance over the stock CIS. Unless, you consider it an improvement over a non running CIS car, I guess.

Posted by: james2 Dec 2 2008, 03:51 PM

Posted by: zymurgist Dec 3 2008, 05:46 PM

QUOTE(Brett W @ Dec 2 2008, 02:56 PM)

Posted by: andys Dec 3 2008, 06:26 PM

Not here to question which is the better performing system, but for years before EFI, etc, center mounted carbs were used on flat motors everywhere. In the late '60's, we ran a G Prod Corvair in SCTA with a center mounted 4 barrel. It was indeed very fast (only 2 MPH off the record the first time out). Race car it was, but throttle response was fantastic (It was one of the things that stuck in my memory) even with those long runners.

Back in the '70's when my '73 2.0 914 left me stranded on several occasions (there simply wasn't the knowlege of EFI then), I adapted a small single barrel card to get me going. Worked fine (meaning reliably) until the Weber 40's arrived.

Andys

Posted by: scotty b Dec 3 2008, 06:38 PM

how about running DUAL quads ?? You know, one four barrel on each side ???