Thread: Gt30-76r
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911nut 911nut is offline
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Join Date: May 2001
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Originally Posted by 911st View Post
I guess the question is what is the ragged edge?
The ragged edge is when mass flow and pressure ratio converge at or very near the choke line.

Originally Posted by 911st View Post
I agree about fitting the compressor to run efficiently. Most street cars I believe we want the peak efficiency at the TQ peak. Some track builds try to move the efficiency island closer to the peak HP.
However, using a larger compressor wheel to run more efficiently has to be at the expense of response.
The beauty of the ball bearing turbo is that you can have it all. The GT 35 will have head room for higher boost, good flow at high engine speeds and spool up quickly due to low friction.

Why spec a turbo that is good down low and runs out of breath up top? If that's the case, save your money and keep the K27.
Paul B.
'91 964 3.3 Turbo
Port matched, SC cams, K27/K29 turbo, Roush Performance custom headers w/Tial MV-S dual wastegates, Rarlyl8 muffler, LWFW, GT2 clutch & PP, BL wur, factory RS shifter, RS mounts, FVD timing mod, Big Reds, H&R Coilovers, ESB spring plates- 210 lb
Old 10-22-2010, 03:44 PM
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