Corleone

$650! Not the hole truth. You also need other springs and retainers, will be another $300.

J Chen

Duke,
I don't think it's a matter of being scared. It's more to
do with finances I guess. Most of us aren't racing
teams with big buget. No body would wants to make
the mistake of buying the wrong thing. Besides most
are street driven cars so we have different requirements.
Regards to Chris Pack's turbo, I strongly suppect that
it's a GT turbo from HKS.

Andrew Wojteczko

Does anyone know how a .58A/R T4 turbine compares with the .82A/R GT3071R turbine? Is the sizing close? I understand they are both 3" outlets, and that the .58 A/R T4 is the largest turbine you want on the 2.5L.

Thanks,

Andrew Wojteczko

pk951

My Swiss is using a 58AR on turbine side not bad full boost at 4000rpm. He tried a 70AR found it to big for his needs, much more lag.Coming out of corners way to slow to spool.

Chris Prack

The turbo in my previous post used a .87 A/R turbine housing. The street 89 car I did was the same turbo with a .73 A/R.

Andrew Wojteczko

Chris, are those A/R's on a T4 turbine?

Chris Prack

No they are specific to the turbo group IIRC. I don't work any longer at the shop where this work was done.

J Chen

The T4 is a huge mother. Myswiss's car is
ex Tony G's. So, Andrew you can judge from
there why the AR's went down. My suggestion
to you would be to go down to the turbo shop
& do a physical examination & make your final
choice. I learned alot by visiting turbo shops.
If my memory serves me correct, the .82 is not
that big but the problem is that our cars being
4 cylinders have a longer time frame between
each cylinders power stroke as compared to a
six cylinder engine like the Nissan Skyline or
Mazda RX7 for that matter.
Exhaust pulse does determine boost threshold.
Even if yours is strickly a track car it is still a
better decision to go with good boost threshold
over unltimate HP. You decide.

Edman951

Andrew,
Nice car man, really like the dash and everything else in that race car.
Food luck with the project.

One thing is for sure, its easyer to change the housing if you don't like it. Then buying a new turbo. So go with what you feel will work. And change the housing later.
Oh wait its true, with the .63 it 2-1/2'' and the .82 is 3''. So if you change housing later the downpipe must be modified.

I still say got with the .63. I don't think you will loose that much top end.
Specially that you don't really want your max HP to be at redline.
I feel its better to have max hp 500 rpm from the redline. then right on it.

MooreBoost

friend of a friend has a custom gt35 that im going to take a look at tonight. i guess it has billet 35 housing and gt40 insides. he says the turbo is made for a 2.0l to 6.0l engine and has quick spool(whatever that is). the engine i would put it on is 2.5l darton sleeves and wiseco pistons. sfr stage 2 header and custom intake and custom head are in the near future. does this turbo sound to big? i might pick it up anyways if the price is right

CPR

with GT40 guts? Yes, I would say to big for a 2.5L....maybe even large for a 3.0

KuHL 951

Seems hard to believe it's made for a 2.0L to 6.0L. The
Garrett on my 6.0L liter truck is freaking huge compared to my Garrett T3/T4R. That's a pretty wide displacement range and it's hard to believe it would perform efficiently at all points in between.

MooreBoost

just got off the phone with my friend and he said this turbo was built for a 2.0 wrc car...lol

MooreBoost

wish our cars reved to 9k

KuHL 951

If it's a ball bearing turbo you need a restrictor installed at the oil inlet of the turbo. Without a properly sized restrictor you will blow oil everywhere since the OE KKK turbos were journal bearings and required oil pressure, not splash lubrication like a ball bearing. Garrett determines what size orifice you need from the oil pressure of your model of engine.