LS1LT1CAM

what is the most power anyone has made with a 76mm on an ls motor

434strokergt45r

iTrader: (-1)

I have seen 1100hp out of a good 76mm

Bird-Of-Prey

iTrader: (23)

I have heard and read many posts that say my GT42-76 is good to 1250 fwhp so say about 1000 rwhp. If not I hope that it can be made into an 88mm. It's a large frame turbo with a 5" inlet race cover.

OneBadTA

Supra guys are doing around 950whp with them. Supras use a higher pressure ratio then our v8's though so if the turbo has better flow and effeciency at higher PR then the turbo might not make 950whp on our engines.

355TurboLT1

iTrader: (11)

I think what you also need to ponder is how much back pressure is this thing going to have at 1000hp! It will be screaming its guts out. A pt88 would be a much better choice. At the end of the day if both setups are equal, the pt88 will monkey stomp any 76mm out there and barely break a sweat doing it, pound for pound.

Bird-Of-Prey

iTrader: (23)

I agree with both of you guys. I do believe it was a Supra that made the 1000rwhp with it. I'm not anywhere near that kinda power. It's a street car. I'm just saying I think it's one of the highest flowing 76mm turbos out there. My info might be outdated as it's been a few years and I haven't kept up much on the new turbos.

DrTurbo

iTrader: (3)

GT42-76 will make around 950-1000rwhp on a 2JZ. One of our customer switched from a Supra to a LS based vetter. Used the same turbo he had made 930rwhp with (GT42-76- 1.15A/R). On the Vette is was doing at just a tick over 800rwhp and backpressure was through the roof. Low PR's and turbos don't mix, so that is the reason behind the larger units on Ls based motors. Same reason with GT47's. So see a supra make 1300rwhp with a GT47, but 900-1000max on a LS based motor.

OneBadTA

Thanks for explaining that a little better. That's exactly what I was getting at about choosing the turbo based on it's PR and flow rate instead of it's max flow rate. Twins are a much better idea if looking for higher numbers. You stay in the effeciency range of the turbos and the they provide alot of flow at the low PR.

mightyquickz28

iTrader: (8)

What is the "Pressure Ratio" and how does one arrive at that number? You said Supras have one and the LSx have another. How is the number derived?
THanks guys,
Dave

OneBadTA

Garret explains it best.
http://www.turbobygarrett.com/turbob...o_tech103.html

I usually just use a compressor calculator to figure out what would work for the setup.
http://www.squirrelpf.com/turbocalc/index.php