Hey guys,

I've got a Jeep which I offroad almost any chance I get. However even with the inline 4.0L six it's a bit down on power, it could use a kick in the *** on the trails and around town wouldn't hurt too
So I'm looking into turboing it. However I one problem I'm having is choosing a turbo to use. I'm use to small displacement high revving engines so my normal choices are out. What kind of turbo can I use on this thing?
I'm looking for boost to come on earily, only revving to 6000rpm and I want it to pull to redline. Also only going to run 8psi.

What about tuning? What could I use to tune the thing? Mega squirt?

 

go with a saab 900 t3.

cheap, small enough to spin early, and big enough that it wont bug out on the jeeps whopping 5k of revs

i was planning on doing one of these for my bro in law, which he backed out on, so i took his t3 for my car.

For tuning I was going to try out the good ole AFC hack style of things. From what I hear the ignition mapping on the jeeps is pretty timid, so I wasnt too worried about the advance under load issue.

 

ive got a saab t3 if you need it, pm me for more info...

 

Thanks man.
I think it'll really help the truck out. I'm getting it tuned professional so maybe I'll go talk to the shop themselves.

I'm guessing I should get some bigger injectors too. If stock is 19lbs should I step up to 21 or 23lb injectors?

 

For a 4 liter motor, I think you want something bigger than a T3. Try something along the lines of a grand national turbo (I forget which one they run).
My wife has a wrangler with that 6 in it. So much room in there for turbo stuff. I think that would be a great project.
Erich

 

The Saab T3 is probably too small.
You dont have to rev higher to make more power. In your case, you just need low end power, so forget about 6k RPM. You want a kick in the pants at 2-4k RPM, you can shift after that. Its not like you're looking for high speed on the trails.

 

Thanks for the info guys.
I'll look into the GN turbo.

 

i have actually thought about making a turbo cherokee 4.0l myself. i can imagine this would be a tourque monster from hell.... and one point of interest a supras inline 6 is only a 3 liter and also having 24 valves doesnt always mean it is that much bettter than 12. i bet the turbo 4.0l would scare the crap out of most people, never seen one done but it would be nice to know how it runs. i would probally use a turbo no smaller than a t3/t04e.... prefferably a standard t4. i would advise against putting a used turbo on it, i have had all bad experiences with used turbos esspecially on larger engines.

 

sry i forgot to mention fuel management, mpfi right anyways i would use dsm blue tops and an s-afc will work just fine to tune or maybe even an fmu if you want to cheap out.

 

GN's have the standard .60 T3 compressor also found on Manual T-birds and XR4Ti's.