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Mines Cat Back Results

sav man

By sav man,
in R35 GTR

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sav man Grand Master

sav man

Posted
Posted (edited)

http://jdm-insider.com/Blogs/Eric/?p=540

You should go and pick up a copy of the February 2008 copy of Option Magazine. Hiro the editor in chief just sent me a copy because there’s a feature of Cosworth in it. Aside from the fact that there’s a bitchin feature of Cosworth in it (and a picture of yours truly with a stupid ass smile), the main focus of this issue is the R35 GT-R. There’s also a R35 GT-R catback exhaust test in it where some shop fabricated a titanium catback exhaust and the car made 507.9ps (500.95hp) at the flywheel. Granted, this test was conducted on a Dynapack so it probably read 5% or higher than any other dyno, but the gain of 22ps is for real. If you can’t do the math, that’s 485ps from the factory which is pretty god damn buff already considering the car is rated at 480hp at the flywheel. The boost went up by 0.1kg/cm^2 (1.42psi) due to the reduced backpressure, but this also tells you that the car has some serious potential from the factory. By looking at this exhaust I can guarantee you that it’s louder than hell so I wouldn’t expect a 22ps gain on a production catback exhaust though. Excuse the shitty scans…

r35.jpg

r354.jpg

r353.jpg

look at the last pic, how bloody rich does the thing run.

Edited by sav man
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scathing Grand Master

scathing

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Posted

The A/F doesn't surprise me. Most cars designed for cruising at high speed run rich to preserve the engine.

I remember reading an interview with Peter Luxeon of APS in a Motor Magazine, and he said they managed to pull 20% more power out of a 996 Turbo by leaning the mixture out. He said if you were sitting on an autobahn doing 250km/hr for several hours then the overly-rich mixture made sense, but when most of us don't sit at more than 120km/hr for any length of time its a waste of fuel and power.

Given that the R35 GT-R's aero and suspension was engineered so the driver could sit at 300km/hr without tiring them out, you'd expect they'd do the same for the engine.

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