[9986paulk]

Yeah they are a little big. They only have 5 psi at 3k. One of these would be really good on a stock engine I think. And btw, it is a Mustang Dyno that seemsto read lower. I've ridden in 300 hp cars and they pull nowhere near this hard. A track time is really what I need sometime.

And yeah, there is no way it's the kit. It should actually perform very well with a built engine just the way it's built.

And it's only 7 psi. I wouldn't expect even 300 on this dyno with 7 psi from anything I'd put on this car witht the stock engine. I planned on 10.4 psi but I didn/t have the extra vac hose to run boost from the manifold. Right now it's run from right after the turbos.

And what do you mean by good fuel JT? What turbos that come in t3/t4 would be better?

[JakeM]

Originally Posted by JTs03v6 It's not the engine or the kit. The problemb is turbo selection. I have said from the begining of mikes build they are to much turbo for his setup. Although they would work very well on a 4.3l stroker pushing 600+rwhp. At 320 bhp these turbos arent even starting to breath. Here is a graph of a super 50T(to give an idea), the pte billett 5557 out flow this turbo by quite a bit considerig a single 5557 flow enough power to hit 500rwhp on a 4 banger. 320bhp on the super 50t... 500bhp on the super 50t (still not at peak effiency)... and btw...both the above graphs were plotted using 3.8l engine 14psi on some good fuel and those turbo's will scream.

This! By good fuel, he means something that will resist detonation a bit better. I say up the boost and get a really good tune laid down and you should exceed your goals. If you are that far out the the turbo's efficiency range you may think about swapping them out for something a bit smaller if that doesn't work. Why throw more money in parts at it if what you got will do you?

[JTs03v6]

A single 5557 t3 .82 a/r on a stock 38 would work. I built a kit early this year using a 5857 .68 t4 and was remotr tuned by justin...made 358/382 sae on 12.4psi. Stock 3.8l and pulled all the way to 5800rpm abd full boost around 3k.

As far as a good turbo for twin setup...that depends on how much power your looking for. I like the mitsu 16's for a stock 3.8l.

I'm going to run a 6262sp on my car(built 3.8l). For a 4.2 stroker I'd recomend a 6265 or even a 6765 depending on how much power your shooting for. Check my youtube page for my 6262 build progress.

[ESG-642T]

Originally Posted by JTs03v6 A single 5557 t3 .82 a/r on a stock 38 would work. I built a kit early this year using a 5857 .68 t4 and was remotr tuned by justin...made 358/382 sae on 12.4psi. Stock 3.8l and pulled all the way to 5800rpm abd full boost around 3k. As far as a good turbo for twin setup...that depends on how much power your looking for. I like the mitsu 16's for a stock 3.8l. I'm going to run a 6262sp on my car(built 3.8l). For a 4.2 stroker I'd recomend a 6265 or even a 6765 depending on how much power your shooting for. Check my youtube page for my 6262 build progress.

I've got a 6765, its an awesome turbo for sure. Does precision release the compressor maps? I want to see the 5557 vs the 3076

Finally ditching the procharger?

[JTs03v6]

Nah, pte dont do compressor maps. I wish they did though. I picked this turbo after speaking with patrick at pte who is a big buick gn guy. From searching the 6262 is close to the gt35 but is rated for more power.

[ESG-642T]

Originally Posted by JTs03v6 Nah, pte dont do compressor maps. I wish they did though. I picked this turbo after speaking with patrick at pte who is a big buick gn guy. From searching the 6262 is close to the gt35 but out flows it.

Yes that's pretty much where I figure everything out about Precision turbos based on the GN

[JTs03v6]

Originally Posted by ESG-642T Yes that's pretty much where I figure everything out about Precision turbos based on the GN

Oh believe me, I did a ton of research on gn receipes as well. Thats where I choose the 5857 turbo. Most go with the cast wheel version, we went billett sp housing all the way.

[9986paulk]

Originally Posted by JakeM This! By good fuel, he means something that will resist detonation a bit better. I say up the boost and get a really good tune laid down and you should exceed your goals. If you are that far out the the turbo's efficiency range you may think about swapping them out for something a bit smaller if that doesn't work. Why throw more money in parts at it if what you got will do you?

By asking what he meant by good fuel, I meant like 93 oct pump gas is sufficient? For like 13-15 psi with the stock cam. It depends where that puts me. I'm shooting for like 370-380 bhp. Or probably 315-320 rwhp on this dyno (with a better power band than the last time, of course)

[JTs03v6]

93oct, 14psi with completelly stock engine, 14-15* of timing, and 11.5 afr should be pretty safe tune and "should" make around 400rwhp on a dyno jet.

Also keep in mind...400rwhp with a turbo is like 370 with a blower. Your no longer using power to spin the blower.