Turbo setup questions

[pimpium2]

This isn't GN related, but since you guys know your turbos I thought I'd see what you think.

The car: '98 Monte Carlo, 3800 series II engine, FWD (I can hear the groans already!)

Up until recently I've had a Paxton Novi 1000 bolted to it, which was good for about mid 13's on 10psi. Stock the car went mid 15's.

What we are planning on doing is putting on a Turbonetics T4 60-1 turbo, T4 exhaust housing, .69 exhaust ar. I don't know exactly what turbine trim, probably O or P.

The trans is built for low 12's, and that's what I'm shooting for. 3500 stall, and Hoosier QTP slicks.

I'm keeping the engine pretty much stock. Cr is 9.4:1, stock cam, high ratio roller rockers, upgraded valve springs, stock heads and bottom end, 42lb lucas injectors.

The guy building the kit for me has a similar setup running 18psi, and put down 417hp to the wheels. I'd like to run in the 10-12psi range (low for you guys), and rev the engine to 6500 or so.

But anyway, I'm just wondering what the equivalent GN turbo would be for this setup? And what kind of boost/hp numbers you guys are putting out with similar setups? I can't seem to find any compressor maps for GN turbos, and the TE and TA turbos don't seem to line up to the respective T4 trims, which makes things confusing!

Thanks guys!

Clint

 

[nocutt]

Hey clint,
You are giving up on the CSC? You had a nice setup what happened?
Anywayz personally with a turbo you don't want to wind the engine up that high...I will keep it below 6K, remember you are at max TQ earlier in the band.
That is also a nice turbo selection...a little laggy, however with 9.4 CR and loose converter I think you will be very fine..
As for your question, I will put that turbo as a TA61, however with the P-trim I will say a bonified TA62!!
HTH!!

 

[pimpium2]

Good to see you over here nocutt, small world...

I was pretty much at the limit of the CSC with my setup. I'd have to cam it to go any further, and I really didn't want to do that. After talking with Matt over at ZZP I decided to sell the CSC and get a turbo for a little more than a cam would have costed me.

They've had some boost spike problems with their 60-1 kit on one of their cars, but they are using the 35mm Evo gate, which IMO is too small. So we are going to step up to a 40mm gate.

What turbine a/r would you recommend? The 3500 stall I have is more like a 3200 in real life, but I don't want to have to wait until 4500 for full boost to come in.

 

[nocutt]

Originally posted by pimpium2
Good to see you over here nocutt, small world...

I was pretty much at the limit of the CSC with my setup. I'd have to cam it to go any further, and I really didn't want to do that. After talking with Matt over at ZZP I decided to sell the CSC and get a turbo for a little more than a cam would have costed me.

They've had some boost spike problems with their 60-1 kit on one of their cars, but they are using the 35mm Evo gate, which IMO is too small. So we are going to step up to a 40mm gate.

What turbine a/r would you recommend? The 3500 stall I have is more like a 3200 in real life, but I don't want to have to wait until 4500 for full boost to come in.

Yes small world in deed...things are kept real easy and simple here...lol!!

To answer your question...honestly, it all depends on what you really want to do? I will never go past a .76 A/R on the xhaust side...I mean if you are going to be taking the car to the track every hr by the hr then by all means go bigger...but I think you are after the same thing most ppl are after...streetability + drivability, guys are going deep into the 11's with stock .63 xhaust housing here...you have a very potent hairdrier you just need supportive mods...which I know you already have...Like I said the question is "what do you really want to do"?
This is my opinion...go after overall power...you want much area under the curve as oppose to the brief window of max power...this will do you good in every avenue in terms of what you want from the engine...