OldSchool Chevy Turbo setup

[dantheman1998]

Hi This is the first time Ive ever posted on this forum. Ok Here come a BUNCH of hardball questions that i am desperate to find out. I appreciate any help i can get.

I have a small-block chevy with a draw-through turbo setup. The Turbo is large enough that i will need a bigger hood because the turbo raises the Carb 6 inches. I want to go with a Electronic Carb setup on this turbo. The reasons is for reliabilaty and gas milage. Can the carb on a Turbo regal be fitted on a small-block Chevy?What is different on this Carb from regular non-turbo carbs? Can it be used on a different computer? Such as a Caprice or Monte Carlo?

The Turbo Sticks out far enough to hit the air-conditioning on my Monte Carlo. Are the Air-conditioning units modified on a old turbo buick so that it doesnt hit it? Or is there anyting else i can do or any other car that you believe will fit thr turbo without removing the air-conditioning?

Thank U

 

[1badTTA]

OK, my suggestion would be to look at the Pontiac 301 turbocharged engine in the '80 and especially the '81 Turbo Trans Am's. The engines didn't produce all that much power but the ignition and carb could easily be adapted to your application with little fuss.

 

[bruce]

Originally posted by dantheman1998

How are you going to edit the timing and fuel stuff for Turbo use?.

CCC carbs are slick when you take the time to learn them, but it's a long learning curve. Doug Roes' Quadra Jet book is an excellent source of how to rework them.

You have a very impractical idea, in all honesty. But, they can be excellent working experiences.

 

[b4black]

Re: Re: OldSchool Chevy Turbo setup

Originally posted by bruce
How are you going to edit the timing and fuel stuff for Turbo use?.

The secondaries aren't under ECM control, so there's room to work there. With a CCC HEI, the initial timing can still be altered and the total timing can be retard via an ignition box like a MSD BTM. Not as nice as burning PROM's, but nobody speaks CCC. I don't see why it wouldn't work well.


What kinda of draw thru set up do you have? The Buick/Pontiac draw thru sits on top of the intake, while many aftermarkets sit off to the side (which sounds like what you have).

And what year Monte Carlo? (Do you already have a CCC/ECM engine?) It will help to know what you have. Does it have a knock sensor?

FYI, there were Turbo Monte Carlos
http://www.flash.net/~rjgeorge/montecarlo.htm

 

[dantheman1998]

The Turbo sits almost on top of the left vavle cover. It sits high and sticks out far to the left.

To make the Setup up work with a regular carb, I would have to rejet and plug the power vavle and run a line to the manifold so that it referenced off the vacuum of the engine and not the turbo. I not sure how a electronic carb works. But if the electronic rochester thats in a Monte Carlo was used for the Pontiac 301T and the Buick then I know its not impossible. Does anybody know the difference in the Turbo carbs to the regular ones?

Also what about the knock sensor? How well is it at preventing detenation? I still plan on running the MSD unit and I have a Vacuum advance that retards under boost.

I will porbably get rid of the Monte anyway, but there are still plenty of cars with REG electronic carbs. Does anybody know what size rearend is in the Caprice?

 

[dantheman1998]

http://www.jason.fletcher.net/tech/turbo/turbo.htm

Go down to the engine with the twin turbo setup. Its like that except that there is only one turbo on the left and the pipe that goes from the turbo to under the carb goes toward the altenater.

 

[b4black]

Re: Re: Re: OldSchool Chevy Turbo setup

Originally posted by b4black
(Do you already have a CCC/ECM engine?)

It would help me help you if you could answer this question.

The CCC carb does not have a power valve. It is basically the same for a NA or turbo applications. If you already have one on the engine(?), I would use it instead of getting another.

The knock sensor is excellent at preventing detonation. That's what it is for.

Vacuum advance distributor and a CCC carb? I would suspect that without knowing the crank position (because of the non-CCC distributor), the ECM will have fits and go into open loop, which would defeat the purpose of the CCC. I think you should go CCC or non-CCC, not something in between. Go with what you already have (whatever that is).

 

[dantheman1998]

I was just using the Monte as a example, It does not have a ccc carb, but i will be gettting rid of it soon. I want to get a car with CCC carb on it.

Suppose i got a CAprice with the 305. I put my 350 in it and get it to work with the ccc carb and without the turbo, It works fine, now i put the turbo on it, I am not sure how the stock computer will act? Since it uses a carb, I want to know what i would have to do to the carb to make it work with my turbo. I am not sure how a CCC carb works. does the computer controll the mixture? Or is it still done off vacuum like a regular carb? ive never seen one. Whats different on a Buick CCC carb over a regular CCC carb? What kind of error codes could i possibly get? What do i have to do to get the CCC carb to work with my Turbo?

 

[b4black]

You won't have to do anything to the carb (except relocate it). Buick's use the same carbs as other GM cars, but each is tweaked to engine/emissions combo it is on. Yes, the ECM controls the air/fuel mixture. You'll just insert the turbo between the carb on intake manifold.

The unknown is if the ECM's pre-programmed timing and fuel curves will work acceptably. This I don't/can't know. The only way to find out is try.


I don't see a CCC set up being any more reliable or fuel efficient than a non-CCC, especially after adding the turbo. The non-CCC will be more flexible and is probably a better starting point for a custom application, IMO.

I guess what I'm trying to say is non-CCC would be my first choice, but if I already had a CCC car, than I would try it out first befreo ditching the ECM.

 

[fc227]

For the carb. You might want to think about a Holley, I reworked one, it works great. You do have to put a check valve in line so you don't POP the power valve. This may not be a bad Idea for the Q-jet either

The AC, you’ll have to look around for different brackets or make your own.


What times are you turning? How much boost? And what are the engines base compression ratio?

I would try to retro fit the ECS out of the Buick V6 HEI dist into the Chevy V8 HEI dist. It should fit and keep the V8 reluctor and pickup. I have not done this before but it should fit. Take a look. With a little work. Then you will have a knock control. That can be used to trigger a MSD box. If it doesn't work o-well. You can bolt the stock HEI module back in.

Just a thougt , what you do is up to you.

Keep us posted.