: turbo-charging a carb'd motor...


HighHooder
12-02-2003, 05:42 PM
so I have this draw-thru turbo system (draws air/fuel thru turbo) how could I convert this to a pusher-type system???


the carb attaches to the opening in front on the turbo itself, can a carb-hat of some sort contain the 8lbs +/- pressure???
http://www.film.queensu.ca/cj3b/Photos/Tech/Pinto/McHughPinto.JPG

Jrod-13
12-02-2003, 06:02 PM
bolt a carb on the intake, and then modify the inlet to push into the carb, then get a hobbs switch to up the fuel pressure for boost.

JParuBob
12-02-2003, 08:18 PM
One thing that they showed to do in a magazine (hot rod) was enclose the carb in a sealed box. what this does is allow the carb to basically flow almost 2x it's rated CFM.

PM me if you want me to bust the mag out and quote it word for word.

Gordon
12-02-2003, 08:47 PM
You gotta do wierd stuff to the carb to make a blow through turbo setup work good. Check out the old school HP book by Hugh McInnes. explains how to modify a vacuum secondary carb to have the secondaries controlled by boost pressure, That makes things tunable.

I don't see how hobs switches adjusting fuel pressure would work on a carbed motor, but I don't know.

enclosing the carb is the way to go. otherwise you have pressurised air fuel squirting out throttle shafts, and all kinds of other problems.

mj
12-02-2003, 09:20 PM
then get a hobbs switch to up the fuel pressure for boost.

exactly how does that work?

mods
boost reference the fuel pressure regulator so the relative pressure stays constant

on a holley feed additional fuel through the PVCR so you can keep the main jets small for off boost driveability

start main jets fat and tune down to safe A/F

UPOVR
12-02-2003, 09:21 PM
There's a publication(newsletter) published out of Florida called "Turbo Safari", or "Real Safari"... something to that effect written by Dick Datsun. Holleys can take up to 15lbs of boost before the seals and body can't take no more. The floats have to be replaced with the foam core type to keep them from imploding. A box can work but in my opinion a lot of unneccesary work for the small amount boost that you will probably want to use.
The publication mostly covers AMC and Studebaker motors but, a lot of the info/tech is transferable to other makes/set-ups.
To get an idea of the power available with blow thru:
There is one Stude from Indiana (called the Chicken Hawk)running a bone stock Stude 289 (stock heads and crank) with a homemade sheet metal aluminum intake, twin turbo's (T04's) and dual 4-barrels running consistant 10.60 sec Qtr's w/ a 3200lb car and 10" slicks. I think he's running upwards of 18-20lbs of boost!

You'll want to be running a small turbo (as you probably already know) to build the boost fast and at low rpms for crawling.
I saw one stude that had plumbed in a radiator neck on the boost side of the turbo for a blow off valve. He just changed the caps for differnt boost settings.
Anyways, do a search for the publication and author that I mentioned above and I think a lot of your questions will have been addressed and you can find some info that your looking for.

CRAZY MATT
12-02-2003, 11:02 PM
Should make it a suck threw stetup- but the bad thing about that is that fuel goes threw the turbo ( lots of turbo bugs are like this and ray jay used to have kits for pinto motors and stuff liek taht)


A blow threw setup would need the carb pressurized. Mopar hadda car witha 340 that was turbo'd witha carb. It had lots of problems and the floats in the carb would collapse from "boost"

Mcstiff
12-02-2003, 11:05 PM
Why do you want to switch?

Wideopen
12-03-2003, 12:16 AM
Draw through setups have such a slow throttle response, And the intercooling possibility's just are not there. As where a trusty blow through setup, Has great throttle response and such. The crushing the floats thing, Can be an issue, But aslong as you have floats that can take it and a proper blow off valve, You should normally get away, With out to many prob's..
With a blow through setup, You'll want to run a 1:1 fuel preesure regulator in refrence with boost( cannot be ran after throttle plate). I know for a FACT a holley can take alot of boost, You'll want to replace the float bowl gaskets as they like to go around 15+ pounds, Even NEW holley ones will take it, But after many jet changes, ANd years of use the gaskets will become a giant fuel I.V.
I have lot's of experience with turbo'd carb'ed toyota motors and have done a few blow through setups on chevy V8's, So feel free to shoot any questions, And i am sure between somebody we can answer it....

HighHooder
12-03-2003, 10:14 AM
Originally posted by CRAZY MATT
Should make it a suck threw stetup- but the bad thing about that is that fuel goes threw the turbo ( lots of turbo bugs are like this and ray jay used to have kits for pinto motors and stuff liek taht)


this set up is an Ak Miller/Rayjay turbo set up for 2.0L Pinto.

I've just had A LOT of people warn me about "turbo-lag" while wheeling:eek::eek: as in "I NEEDED THROTTLE THEN, not now":shaking:

just second thoughts on an incomplete system

JParuBob
12-03-2003, 11:46 AM
Originally posted by HighHooder


this set up is an Ak Miller/Rayjay turbo set up for 2.0L Pinto.

I've just had A LOT of people warn me about "turbo-lag" while wheeling:eek::eek: as in "I NEEDED THROTTLE THEN, not now":shaking:

just second thoughts on an incomplete system

here is one thing that I don't get in reference to wheeling and turbos. most of the time when I *really* need the power, I'm already running around 3-4k RPM, so the boost should already be built up at that point. With a smaller turbo, you should have most of your max boost built by 2500 RPM or so, so you should be fine (I would think).

CRAZY MATT
12-03-2003, 12:20 PM
If ya want throttle response witha turbo, run a grainger valve , port the exhaust mani, swingvalve and run 3" exhaust


witha non intercooled motor it should be pretty responsive

CRAZY MATT
12-03-2003, 12:25 PM
why not swap a factory turbo motor in? I have a friend that has a merkur x4ti that runs a 12.8@ 110mph and the motors stock - for mods it hasa IC, ported intake/ exhaust mani's and ~25 psi of boost - plus it runs on mopar electronics:D

CRAZY MATT
12-03-2003, 12:28 PM
Originally posted by Wideopen
Draw through setups have such a slow throttle response, And the intercooling possibility's just are not there. As where a trusty blow through setup, Has great throttle response and such.


I beg to differ on that my last suck threw car ran badass and got on boost hard enough in 2nd to burn the tires off.


Most reasons suck threw stuff is laggy is because of the exhaust is restricted or ur not running a grainger valve ( ie keeping the wastegate closed)




blow threw stuff is not laggy most the time till you intercool it

HighHooder
12-03-2003, 01:18 PM
Originally posted by CRAZY MATT




Most reasons suck threw stuff is laggy is because of the exhaust is restricted or ur not running a grainger valve ( ie keeping the wastegate closed)



m

well, I don't have a wastegate on this system:eek: should I be concerned???:grinpimp:

all the porting and polishing and gasket matching has already been done (just short of race specs)

and I'm into this motor for more than it's worth so switching to a turbo block (xr4ti) is monetarily out of the question.

CRAZY MATT
12-03-2003, 01:25 PM
Sweet no waste gate:D



can always just inject it with a intake manifold and use a different distributor - does a 2.3 intake bolt to a 2.0 head?

HighHooder
12-03-2003, 01:31 PM
Originally posted by CRAZY MATT
Sweet no waste gate:D



can always just inject it with a intake manifold and use a different distributor - does a 2.3 intake bolt to a 2.0 head?
no on the intake question, but at http://www.esslingerracing.com/catalog/contents.htm I can get pretty much everything I need to inject it for around $1200 +/- ... if I only had an extra $1200... :idea:anybody want to buy a piece of glass:flipoff2:

Jrod-13
12-03-2003, 01:35 PM
this (http://www.toohighpsi.com/BudgetTT/tthowto.htm) was the one page I had in mind for the blow thru setup.
It's a larger motor than yours.. but running 10.4's @ 132mph, on 15psi, using a 600 holley, junk yard parts, and PVC intake piping is pretty damn impressive to me..

CRAZY MATT
12-03-2003, 01:44 PM
Originally posted by HighHooder

no on the intake question, but at http://www.esslingerracing.com/catalog/contents.htm I can get pretty much everything I need to inject it for around $1200 +/- ... if I only had an extra $1200... :idea:anybody want to buy a piece of glass:flipoff2:


That sucks!!!

might be doable to builda intake from scratch or usea 2.0 intake flange on a 2.3 intake with a custom plenum. Could always add some injector boss's to the intake u havea and makea plenum to bolt to the intake as is


It should make 300hp easy if ya got the right parts in it


does a 2.3 head bolt to the 2.0 block?




Whats the motor going in?

HighHooder
12-03-2003, 01:44 PM
this is what I was wondering if I could do:grinpimp:
http://www.toohighpsi.com/BudgetTT/Images/engine1.jpg

looks "doable"

HighHooder
12-03-2003, 01:46 PM
Originally posted by CRAZY MATT





It should make 300hp easy if ya got the right parts in it


does a 2.3 head bolt to the 2.0 block?


Whats the motor going in?

a cj3b

http://www.film.queensu.ca/cj3b/Tech/PintoEngine.html

CRAZY MATT
12-03-2003, 02:01 PM
sweet project

should have plenty of power for those pesky V8 jeeps should make enough tq to destroy the drivetrain too :D