Old Slow Coach

I sold my FD, but am helping the new owner reach his goal of 600 whp. I'm searching for the turbo that offers a balance of the best response and highest top end, which means most area under the curve. Motor will have an extened street port.

I know of forum members who hit the 600 whp mark with streetported motors and T-51kai and s300 (66mm) turbos. I don't remember exactly how many pounds boost they were running, but I think it ranged from 27-28 lbs. Anybody remember what PSI LUPE was running and at what RPM he began to spool?


My goal is to spool faster and breath longer than these guys. What turbo set-up has the best combo of compressor/turbine wheel technology/size to do this? I know that A-Spec has tweaked some combinations, but I don't honestly know which combo is best, or if there is another company offering something equal or better.

Thanks!

Here's the car (click to enlarge):

smg944

iTrader: (34)

t04z with a big turbine a/r seems like what you would need.

dhahlen

iTrader: (5)

I'll be able to give you better answers around October when my T51r setup is complete with my race port.

I expect around 750hp, and should hit the 600hp mark around 20-23psi.

The turbo on LUPE's care would start spool around 4500rpm....

charlies7

iTrader: (4)

^psshhs all talk

Old Slow Coach

What's the exact difference between your turbo and LUPE's? I'd like this thread to be really specific about compressor/turbine wheel sizes.

dhahlen

iTrader: (5)

You definitely want a BB setup, that will help your power curve.

Also, Charlie is jealous cause his *** can't afford a real setup.

darkphantom

iTrader: (2)

T51 600hp under 30psi easily with a street port
GT42R 630-650 @ 25psi or higher with a street port
T88 600hp @ 32psi street port. anything bigger
T78 550 @ 27psi small street port
T04Z????

Old Slow Coach

Only one of these will provide the greatest area under the curve- Which one is it? That is the whole point of this thread.

Also, since the goal is 600 whp, wouldn't A-Spec's GT4094R spool faster than any of the one's you mentioned.

What about the 500R??? It spools fast, but can it provide enough up top?

classicauto

iTrader: (3)

I think there's some good suggestions here, but I think the level of optimization your looking at is going to need more thought then simply size and frame. You're going to need to look at manifold construction, wheel speed, manifold pressure, intake design.....

I'd contact A-spec to see if any of his secret combos pop into his head for fulfilling your goals.

ErnieT

iTrader: (2)

This is all you need!

Old Slow Coach

Are you saying that there's not a turbo with better response that'll get me to 600 whp?

dhahlen

iTrader: (5)

That's just Ernie being Ernie.

If you want good response and tons of HP, go with a twin setup. You can get your low-mid and your high end.

As far as single, crap I can't remember dude's name. He just had his car tuned and made 600hp - it's a Red FD and he just put it up for sale... tune by PFS iirc. He had a pretty nice curve.

mr2foryou

^That would be Greg(BLitzed33). His car is sold now. Modified R85/s300 turbo @ 28psi and full c16 race gas with a street ported engine. 610rwhp

ErnieT

iTrader: (2)

Not at all. Yes I was being a smart ***, but the dual ball bearing GT42R with the 71mm compressor and 1.05 A/R on a T6 frame will spool to 30psi by 4800rpms. I don't know what turbo that will make the same power, spool as fast.

BLitzed33

here is my dyno with boost curve if this helps...its a borg warner with a 66mm compressor, 80mm turbine wheel and a 1.15 a/r. getting the back pressure out is KEY at that boost and rpm, so make sure your turbine and turbine wheel are sized appropriately. you must clearance your rotors to housings as well when you start making these numbers for eshaft flex. good luck.

Old Slow Coach

Here's LUPE's dyno graph of the T51r kai at 27.5 psi. The factory specs on this turbo are a 70mm inducer on the compressor and a 71mm exducer on the turbine.

It's interesting to try compare BLitzed33's and LUPE's graphs. Both ran at 28 psi, but have significantly different power curves. There are so many variables (a/f, port shape, tuning, etc.) besides the turbo's wheel sizes. I personally prefer BLitzed33's power curve, but don't know if that is more a result of tuning than the turbo's wheel sizes. Which is it? Or does LUPE's power fall off so precipitously because hot side is too small. Which is it?

crispeed

Especially when you're trying to make a lot of torque at lower rpms also.
People are under the impression that some magical turbo alone is going to do the trick. It's the entire combination.
I use to like a lot of power 'under the curve' as it's called. I have since learned what really matters in the real world though when you're making a lot of power. Don't get me wrong because it does make impressive dyno sheets. Too bad we can't race or drive the dyno sheets.
An enjoyable powerfull setup is one that's balanced and I'm not reffering to engine balancing.

crispeed

You should never compare dyno runs form different dynos.

Old Slow Coach

I realize that the two dyno's will yield differnt numbers, but shouldn't they both highlight the same overall trends? If LUPE's power peaks early and drops off rapidly on one dyno, it's going to do it on the next dyno. The numbers will be difffernt, but the trend will be the same.

Old Slow Coach

The motor has been properly clearanced, I just didn't mention every mod. There is enough intercooling, fuel, spark, exhaust, control and ALL mods to support well over 600 hp.

Help me out, now, and suggest an enjoyable powefull setup that is balanced.

hondahater

iTrader: (2)

I think people have but for some reason you think there is only one turbo out there that is going to do it and the person that has it will just somehow magically convince you that thier turbo is the best. The reason god made the internet was to research and find things out. You heard already from the lions mouth (ernieT) what he uses and what his goals where with that turbo. To me it sounds like that is a very nice setup for you however like everyone else has said. There is no magical turbo out there, it's all about the entire setup.

Old Slow Coach

I'm not looking for a magical turbo; I'm looking for the best combo of wheels. BLitzed33's post was extremely informative because I know exactly what he has and what the performance was. Magic has nothing to do with it. The fact is that my setup is fixed, and if I try every one of the turbos suggested so far, I'll get wildly different results and one will emerge with the best overall balance. This ain't a game of horse shoes!

As for ernieT, he has the 42r. And A-Spec sells something called a 4094r, which will offer very similar power to the smaller 42R in a 40R sized turbo. It is a hybrid of the two. You will see pretty similar power with slightly better response due to the lighter overall rotating mass. If the 4094r can support 600whp up to redline, then I'd say that is a better solution for my goals than what ernieT suggests.

I just don't know if the A-spec 4094r or 500r are better options than everything that's been mentioned. I sent a PM to A-Spec yesterday about this thread and they haven't chimed in yet. I asked questions in the vendor forum and they haven't been answered yet. I'm hoping someone out there might know or could even speculate on it.

BLitzed33

I will let Ray or the customer post about some crazy numbers for the amount of boost put down on a bridge port motor he just did and is dynoing.

hondahater

iTrader: (2)

why don't you just call aspec and ask them?

t-von

iTrader: (8)

Good luck in your search. The most convient way to spool any larger turbo that will give you that kind of power and response in the low range, is to up the engine displacement. There's only so much exhaust energy you can extract from a 13b rotary. 20b projects aren't as expensive as most people make them out to be. Either project is gonna cost much bank. Your friend may as well go with an engine more capable of substaining that kind of power for a longer period of time and also on pump gas. Also a 20b will give you that power under the curve your friend is looking for.