Chris Prack

Back in Jan. I posted a thread on a new line of turbo's that we were using. We did an install on an 89 car with 200+k on the odometer. It made almost 360 rwhp @ 1.3 bar on pump fuel.

Well today we finished tuning the next size up A/R turbine housing of the same model turbo. This is a race car with a new engine that I built. It is sleaved and runs JE's. It is controlled with a Motec M4 and has an aftermarket cam, injectors and bypass valve. It also has a Lindsey intercooler and wastegate and custom IC pipes. We ran Sunoco race fuel.

Btw this is a 2.5 liter engine.

We tuned it on a Superflow twin eddy-current chassis dyno.

It made a best of 452 rwhp and 406 rwft/lbs of torque @ 1.5 bar. It could have made more power but I didn't have any more threads on the bypass to tighten the spring any further and it was lifting open and venting some boost. This as it is is a very big gain from where the car was before so we didn't feel the need to spend any more time going for more hp. Not that we had any extra time as we are on a deadline.

We have a 3 liter at the machine shop right now that will run the big brother to these other turbo's. It's BIG. The 3L is being dry-sumped, will run 16v, JE's, Motec M400, custom IC pipes, etc. The engine that we just completed we hoped would make 410 rwhp and we were pleased it did much better. We were guessing that a 3L with the larger turbo would make about 500 rwhp but now it looks like we may be too conservative with our expectations so I am now hoping for around 550 at the wheel. From what I've seen so far I believe that it is very realistic.

Chris Prack

This is @ 1.4 bar.

Chris Prack

This is @1.2 bar.

Chris Prack

0.75 bar.

Mike B

Mother of God!!!

Congratulations! Those are darn impressive numbers.

Mike Murcia

Wow. 550 w/ a 3L? Insane!

Chris Prack

Thanks! Needless to say that we were quite pleased with ourselves! It's amazing to me that it made that much power with the factory exhaust manifolds and crossover pipe. Not to mention intake. Go figure. I think that this engine would make more power if we spent more time (and money) going after some of the other factory parts but my customer is done for now.

Chris Prack

BTW, I have some pics I can post later.

PCinDC

Wow Are the charts from a 2.5 or a 2.8? Thats gotta be some fun to drive...

I'd like to stop by and see this beast!

westcoastprshe

With a new manifold/crossover, holding boost all the way up, and spinning up to more than 6500rom (tough with a 3L) you could easily put down 550 with that setup, if not more.

I wish those charts had the X scale in RPM.

Chris Prack

Sorry, it's a 2.5. The car is nowhere near street legal anymore. The owner is a long time friend and he and 4 other guys rented Summit Point raceway on Monday for a test day. It outta be interesting.

Chris Prack

I edited my first post to include that these charts are from a 2.5, the 3.0 is still apart.

I always forget to change the wheel speed to engine rpm. You can find 5252 quite easily and we shut it down at 7k.

Red 944

That is amazingly impressive?
What turbos are you using for the various stages?

porshhhh951

This is my question.

Damn nice number's. I am very impressed.

Duke

WOW

Is this with an 8 valve head??

Seems like a perfect turbo match. Comparing the 1.5 and 1.4 bar charts it appears that the turbo is starting to max out near redline at 1.5 bar. Since the 1.5 bar chart is more flat and does not continue to rise as the other charts.

Any chance you will reveal the turbo and headers/crossover?

Really impressive!

EDIT: I now saw that it was done with factory headers and intake!
But what about the modifications to fit the turbo