Turbocharging a 4.3L CPI engine???

[Gordon]

Is it possible to just add boost into the intake on a CPI injection van (obviosly with more fuel,etc).

It's a type of direct injection unlike a carb or tbi that meters air/fuel together.

I figured a pair of dodge 2.2L turbos should be enough to feed the engine 5-7psi safely.

Most stock engines will take 7psi....i think

The motor is already 200hp stock and i've done a few things to it.... opened exhaust to true dual 2.5" and ported/polished the intake.

[97TurboAstro]

shouldn't be a problem...

STS makes turbo kits for a lot of non-turbo EFI vehicles.

I have a turbo kit on my '91. Your CPI should be similar.

Since the fuel pressure regulator is inside the intake manifold, the boost pressure will reach the manifold, and the fuel pressure will automatically be increased.

The thing that'll be hardest will be where to mount the turbo(s). Since the engine in the Astro is shifted to the right a bit, a turbo will fit on the left side of the engine. The turbo is high enough that the oil return line is still a gravity feed to the oil pan... sweet.

There's a link to my turbo install in my signature

your best bet is to buy my van... $2800

[97TurboAstro]

oops...

I just noticed you have AWD. My kit was only for the RWD vans, 'cause the turbo mounts where the prop shaft runs.

You may have to find some Syclone exhaust manifolds and mount your turbo high on the right. That might be kind of tight, but I have seen Astros w/ Syclone setup on Ebay a couple times

... you really should buy my van, though

[Gordon]

I guess I should update my SIG... the new van is a 1995 GMC Safari 2wd with CPI injection.

I'm planning to mount both turbos at the collectors (1 on each side) and use an oil return pump (no holes in the oil pan that way ).


Are you sure the regulator is in the intake?

I'm not sure, but I don't think the stock regulator will auto adjust..

My fuel pump went the other day so i opted to put the higher pressure pump in it (96+) beign as i get them for cost at work.... HUGE difference in power!!!!

[lockdoc]

LOL! You are questioning a guy who installed and documented his install of a Turbo into an Astro? C'mon Gordon. Just pick a project and do it already. You could always do another afterwards if you want something different.

[Gordon]

Questioning as my van is CPI and his is the newer MPI.

My van still runs a map sensor but no MAF that I can find on it.

Goes from air cleaner to TB to Intake with no other sensors that I can find.

[astrozam]

The FPR is most def in the upper intake ( plenum ) of a 95

[Gordon]

I'm still pretty new to this CPI crap....lol

So if you add boost to the intake the computer will auto adjust the fuel pressure (to a point of course).

I know "most" stock engines will take 7psi but i probaby won't run more then 5ish.

97TurboAstro... how much boost are you running?

I'd love your van but i have 2 issues..... 1 your along ways away from me and 2 my job don't pay diddly...lol

[97TurboAstro]

So if you add boost to the intake the computer will auto adjust the fuel pressure (to a point of course).

The computer doesn't control the fuel pressure. A typical regulator has a manifold reference line that runs to it. It will lower the fuel pressure under vacuum (e.g. idle) and raise the fuel pressure when vacuum drops (e.g. WOT or forced induction)

The CPI regulator is just the same... there is a little hose nipple on the regulator that looks like a hose needs to connect to it... but, since the regulator is inside the upper intake, the manifold reference is all around. Works the same for 92-95 as it does for 96-up.

I know "most" stock engines will take 7psi but i probably won't run more then 5ish.
97TurboAstro... how much boost are you running?

I can usually run about 7-8 psi before the knocking can be heard.
I took it to the track once and added 3-4 gallons of 110 octane to 3/4 tank of 93 octane, and I was able to crank the boost to 12-13 without any audible knock. That was fun... ran 1/8 mile version of 14.9x

I'm seriously thinking about removing the turbo setup from my van... It'll sell more easily if it doesn't have a turbo and traction bars on it

Then... I'll be able to sell the turbo setup to someone on here that can really appreciate it...

[Gordon]

I wonder how big of a turbo is too big.... just got a FREE Garett turbo off a Chevy 6.6L TD.

It was a "warranty" return, guy claims it wasn't making enough boost and wanted it switched to the "new" style turbo.

I know it would likely spool pretty quickly but may produce way too much air for the vans engine.

I'll add a pic of it after...

[Gordon]

Ok 2 pics of the turbo as promised.

This thing is FRIGGIN HUGE!!

Just gotta figure out a way to mount this beast under the van like an STS kit.

[Mr_Roboto]

Interesting turboas a guess the compressor will be ~60mm supposedly good for 650hp but based on the maps I've seen 450 is a more realistic estimate. It should work very well on a CPI 4.3L if you can get enough fuel to it. You'll probably need an additional injector setup like the one used by 97turboastro even though you may be able to coax more power out of the CPI system I doubt it would be a ton definitely not 7 PSI worth.

ED:is that a VNT turbo? What year is it from?

[Gordon]

Yes it is a VNT turbo... I don't have the ECM to run it though so I have set it to stay wide open.

I think it's off a 06-08 6.6L Duramax Diesel.

You want it?

I've been instructed by my "better half" to "leave that damn van alone, get another one if you want to play with them".... HAHAHA

At only $12hr it'll take me a while to get another van.

I do have this turbo for sale, the dealership says they are worth... well way too much in my mind so i'm just open to offers on it.