http://ausrotary.dntinternet.com/for...ic.php?t=27778

Are any of you boys doing this already ?

Will be upgrading my FC very soon to this spec

 

i didn't think you could get 400 rwhp from the stock turbo.

 

The turbo isn't even close to being stock at that point. They've pretty much machined or totally replaced all the various pieces.

 

**** man this is a BPU mod, we are talking between $600 to $850 Aus, it's a damn stock turbo with a Garrett compressor wheel in it

Its optional to put on an external gate, did you even read the thread ?

 

ok, does BPU stand for Basic Parts Upgrade? i always see or here this BPU stuff being reffered to supras

 

BPU is bullshit. "yeah i've got a bpu stage 15' once you do more than remove some plastic or a few bolts it's not a BPU.

 

You're completely replacing major parts of the turbo, exhaust, intake, engine management and fuel systems to even get close to 300+rwhp. That's going to cost you a lot more than a few Kangaroo hides -- and if you think that's "BPU," then I'm Mary the god damned Queen of Scots.

 

i think blue t2 was close to it

 

I think you officially just got the award for the first ever use of Australian slang on rx7club.com, well done..

 

BPU is basic power upgrades


haha supra dyno queen BPU stage 25
everything is a BPU on a supra even stroker motors and 5 angle valve jobs and extrude honing

 

Swapping a turbo is very BPU in an RX7, I can do it in 1.5 hours, and requires no weird vacuum line routing, a la supra.

-David Guy

 

...I can see it now. Instead of calling them ricers, we'll call them BPUs.

Oh, wow, an intake. That's so rice!
to
Oh, wow, an intake. That's so BPU!

 

According to rotorworx site:
The unit you are saying is $850aus is rated at just 200rwkw, thats no where near 400rwhp.

And the other " hiflo" they have is only rated @ 240rwkw, and that is almost a full blown to4. Most guys around here think of hyrbids as just compressor upgrades.

 

Yeah, I'm thinking I might have been close to the 400hp mark.

I am working on my stock hybrid S5 turbo again as Rob @ Pineapple works on my engine.

Bryan @ BNR put a larger clipped "P" trim exhaust wheel in it to try to stop the boost creep (had clipped "O" trim).

I just finished a stainless divider for the wastegate passages so that it is a truly divided set-up again. My previous set-up allowed for communication between the scrolls as the wastegate passages dumped into a single 60mm pipe to the 60mm wastegate. Now there is a SS divider that fits between the WG passages and all the way up to the WG valve. I will have pics up soon.

By dividing the WGs I was trying to recover some of the boost response I was afraid I might lose going to "P" trim wheel- though so far every mod I have done to increase overall flow has helped turbo response as well. Maybe it will help top end flow a bit too.

Old set-up. Yeah, still had boost creep...

 

Blue TII-
I wonder if part of your boost creep problem was that oversized WG? And out of curiousity what is the turbine a/r now with that P trim wheel?

 

I wonder if part of your boost creep problem was that oversized WG?

NO!

My turbo started out as a "standard" BNR stage 4 w/ ported stock wastegates and "O" trim wheel. Boost creep over 20psi by 3,500rpm.

Then it was clipped "O" trim wheel and stock ported WGs divided and externally open air vented out the rear of the turbo. Boost creep over 20 psi by 5,000rpm (I found the set-up comes on strong @ 3,500 and then comes on even harder @ 5,000rpm).

Then I did the 60mm external WG and boost creep was moderate (2-3psi) @ 5,000rpm and through the roof again after 7,000rpm... (set-up comes on even harder after 7,000rpm).

Now I have the clipped "P" trim wheel to fight that last bit of boost creep (Rob said the engine was good for 8,000rpm all day and 9,000rpm for overtaking).

I believe my boost creep is from the free flowing 3.5" turbo back exhaust and the ultra low pressure drop intake system I made. I spent soo much time picking out parts and port matching, relieving and polishing every inch of the intake and exhaust systems.

If I put in my exhaust tip silencer I can't even achieve full boost.

And out of curiousity what is the turbine a/r now with that P trim wheel?

AR stays the same as it is a funtion of the area of the exhaust scrolls cross section to the radius from the center of exhaust wheel. I believe it is a 1.00 on S5 turbo, but a small (T3 sized?) 1.00.

Though I did try some other things to improve flow through the exhaust housing, such as widening the scrolls apertures to 2x the width of stock so that it is less restricted.

And tried to aid flow through WG holes as well by porting the WG entrances "lower" and leaving the rear high as well as trying to incorporate good flow seperation to WG holes w/ NACA ducts.

Consquently, the larger T3 exhaust sides and T4 compressor sides seem to be the new hot set-up for the quick spooling 3rd gen guys single turbo conversions using the new more efficient compressors and less boost creep prone exhaust sides of the Garrett GT line up- such as the GT40R. They are reputed to be good for up to 400RWHP.

 

Good info Thxs