95 TBI Turbo Charger!

[Greensmith]

I’ve been researching turbos in-depth for about 4 hours now and have some application specific questions.
First of all, the setup:
1995 ECSB
ENGINE: 383 Stroker
Vortec heads
Ultimate TBI mods on stock TB
stock 350 injectors
TBIchips.com custom chip with fuel pressure spring
HVLP fuel pump
Transmission is a 4l60e with a complete heavy duty rebuild

If you need to know anything else just ask and I'll find the answer.

While the truck has been a blast to drive. I, like most of you, want more power! So my questions to those in the know are:

1. Does anyone know of a successful turbo tbi motor?
2. What, if anything, do I have to do with the computer and or fuel system?
3. Is there any supplementary computer system needed?
4. After what little research I did I guesstimate that a 72-74mm turbo with a .96 A/R ratio will do. Is that even in the ballpark?

 

[TylerZ281500]

your gonna run out of air even with forced nduction on a stock tb, and dont go with tbichips.com he is crap

turbo and tbi dont really play along nice, successful in what way? your not gonna get a ton of performance from it, your limiting yourself with the tbi system right off the bat. gas mileage will suffer, your "performance" wont be off any substaintial gain. so all in all your in for more headache than its worth. theres superchargers that are made for them hell i have one at work, but it takes more than just slapping it on there.

not to bust chops but 4 hours isnt even close to the time you need to spend researching a build like that, youll need excessive datalogging, testing, tuning etc etc. and depending on your budget for it you will go above and beyond trying to turbo a tbi motor.

secondly, 383 tbi are nice, ive built one, my friend has one in his dd but it limits you on cams, and the bigger the cam the more PITA it is to tune.
If it were me, i would highly suggest against it. make yourself a nice N/A carbed motor and swap transmissions if you want easy and more power.

 

[FastOrange]

your gonna run out of air even with forced nduction on a stock tb, and dont go with tbichips.com he is crap

turbo and tbi dont really play along nice, successful in what way? your not gonna get a ton of performance from it, your limiting yourself with the tbi system right off the bat. gas mileage will suffer, your "performance" wont be off any substaintial gain. so all in all your in for more headache than its worth. theres superchargers that are made for them hell i have one at work, but it takes more than just slapping it on there.

not to bust chops but 4 hours isnt even close to the time you need to spend researching a build like that, youll need excessive datalogging, testing, tuning etc etc. and depending on your budget for it you will go above and beyond trying to turbo a tbi motor.

secondly, 383 tbi are nice, ive built one, my friend has one in his dd but it limits you on cams, and the bigger the cam the more PITA it is to tune.
If it were me, i would highly suggest against it. make yourself a nice N/A carbed motor and swap transmissions if you want easy and more power.

Word!

If I had the cash I would look into a aftermarket EFI system.

 

[88GMCtruck]

and dont go with tbichips.com he is crap

Why do you say that? I've had nothing but good experiences tuning with Brian.

 

[TylerZ281500]

His earlier work was good I had a chip from him and it was horrifying I sent it back and it was even worse. I hooked up with my friend who had limited knowledge and we made a chip so the truck would at least yum but then I went to mark on gearhead efi and it ls what im running bow until I can catalog the engine. There's a whole thread ofn people who got screwed by that guy

 

[Greensmith]

and dont go with tbichips.com he is crap

I didn't have a problem with tbichips, it got the truck to run without any problems.

successful in what way?

A setup that makes good power using TBI and a turbo.

4 hours isnt even close to the time you need to spend researching a build like that

I never said I was ready to tackle the project, this thread is merely a means of more research.

Anyway, I assumed going with forced induction, only up to about 10psi boost, would be a way around the smaller TB. I realize you can only cram so much air through there at a time but that seems feasible.
Also, I've never been able to find one of the TBI superchargers. I know they exist, and I've looked, but maybe in the wrong places.

unfortunately, I have the TBI engine and am not looking to swap it out.
This thread is intended to be mostly theory crafting for this specific application.

 

[Crash]

This guys build should give you an idea for physically installing it. Mild cam and low boost should make the tuning easier.
http://www.gmt400.com/forum/showthread.php?15824-Twin-turbo-93&highlight=twin+turbo

 

[sewlow]

I like these.
They have some test results for the install on '92-'96 LT1 Corvettes & the '93-'97 LT1 Camaro's. Don't know if those engines use the same TBI as the trucks, though.

http://www.procharger.com/systems.shtml

There's a couple of members that are using these, but good luck finding one for older vehicles such as our's. They used to be available, but no longer & since have become few & far between. They do pop up on ebay occasionally. Whipple dropped the manufacturing of them in favor of development for the LS based engines.

http://www.whipplesuperchargers.com/default.asp

You'd have to do a lot more research than what these links provide, though. Along with a bunch of testing/tuning & some mad-fab skills.
That TBI is extremely restrictive for any type of boost system, & would probably cause more problems than what the effort to install would be worth.
My preference would be to drop the TBI & go carb. Especially on that 383! A stand-alone trans computer would be required with the elimination of the TBI. A stick shift would makes things easier to dial in, i.e. computer issues.

 

[TylerZ281500]

its not the throttle body its the heads that will be your main issue, drop the tbi switch to a carb like mike did on his turboed truck.

depending on your boost gaskets, rings, everything will need be changed to something better. in simple forms, a tbi engine is not, in any way, a good start for a nice or "successful" turbo build

lt1s are very very different, the heads flow similar to vortecs, not sure but i think they flow a bit more than vortecs do.

your heads on the 383 will kill everyon ounce of power you could make as well. on mine i tried it so trust me, i ended up going with a set of world torquer s/r heads with port work and 1.94 1.5 valves, forged crank, flat tops with two valve reliefs, h beam rods, and the like.

 

[great white]

Off the top of my head, you'll have to do something with the MAP sensor and the programming for sure if staying with the TBI.

The OEM 1 BAR MAP sensor isn't going to work. You need a 2 or 3 BAR and a way for the ECM to understand the data values.....