Question : New turbo install

[Revsracing99]

This what I have:
87 GMC S15
3.4l GM performance engine
700r 4 trans
Holley 502-3 Tbi
Custom ecu
Istalling t3/t4 turbo

I'm going to install the turbo in the place of catilitic converter. Coping what STS is doing with thief systems. I have a few questions I know about getting pressure to the turbo, but short of cutting a hole in oil pan is there any other methods of getting oil out of the turbo? I thought about a sandwich adapter but I think that would run too much oil though the turbo. What kind of pressure are you guys running ( real numbers please). I was thinking of starting with 5 psi to start. With the tbi I have. I figure much more and I will have to start adding fuel nozzles. I. M running a internal waste gate with a mannuel ajduster where do I tap into? I' m also have a pop of valve same deal? Boost gauge take off at intake?
I'm building this system from scratch. Something different than growing a V8 at it. Anything you can throw my way would be helpful
Mike

[IsaacHayes]

You'll need an electric pump to get the oil back to the engine. Unless the turbo is sitting up higher than the oil pan to drain back. You T off the oil pressure sending unit for the feed to the turbo.

That's an iron head motor, not sure how much those can run, but on the aluminium head engines people run 8-10 psi stock without issues. You'll want to be able to tune probably to pull back spark since the iron heads run a ton of spark since they are not fast burn "vortec" style heads. And to add more fuel.

Another option but not as good for power/accuracy is a rising rate fuel pressure regulator and some sort of msd boost spark retard box. Not sure how that works with a distributor though.

[Joseph Upson]

There should be enough room in the engine bay to mount the turbo under the hood. I would never install a remote mount turbo with enough room under the hood close to the engine for it. You can also tap into the fuel rail at some point and install an additional fuel injector just before the throttlebody with a pressure activated switch (like what the alcohol injection kits use) if you don't have the ability to tune. That's the way paxton superchargers use to do it before they figured out how to get into the programming. 7 psi is about the most you can run and manage okay on the stock non boosted ECM programming.

That's probably the best approach on a do it yourself budget build without the ability to edit epromm data because out of boost the engine will run great and your fuel economy will be hardly affected as long as your exhaust system to and from the turbo is not restrictive during normal driving.

A vehicle of that year was designed to run on 87 octane so using a combination of premium, to mid grade mix and an intercooler you shouldn't need to retard the timing since there is already some cushion in the stock spark table.

You can also use an alcohol injection kit and 87 octane and no timing retard and not have any problem with 7 psi. You need an air fuel ratio gauge to know your state of tune because you don't want to lean the engine out.

Me and my cousin were just talking about how much money we could have made had we really taken the ball and ran with it back in 1995 when turbos were most common on Chrysler cars in the U.S. and we seemed to be the only ones experimenting with turbos since Paxston superchargers seemed to be the only boost available on the market.

My first turbo car was a twin turbo TPI 305 IROC Z28, I built the system myself except the lower exhaust. My second turbo car was a 2.8L Fiero with an intercooler and an extra fuel injector, I boosted it as high as 12 psi for a short while before dropping down to 7 psi.

As a student at the time I didn't have the time or interest to develop the idea into what could have made me the Lingenfelter of turbocharging.

[project89]

whats the spark table for a tbi motor look like compared to a mpfi camaro motor?

i ran mine upto 12 psi with my stock timming curve +4* base for over a year

tbi is also map based correct?
if so it wont read boost so i doubt it pull timing back like the maf mpfi system