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      04-11-2019, 10:17 AM   #43
allmotor_2000
F10 1/4 WR: 9.9s / 142.5mph 1/2 WR: 175.5mph
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Drives: 2018 RS3, 991 Turbo
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Quote:
Originally Posted by tonydat1 View Post
That's the story I heard as well for the s55 motor. Ram made 1000whp on a carbahn spec motor and never mentioned anything about valve springs, so I don't think it would be the same for the s63tu.
Don't port the head... you can smoothen out the combustion chamber to prevent hot spots but all those motors with the big shiny ports never did anything.

You need valve springs IF you are going with an aggressive cam, revving the motor much higher (prevent float) or just running so much boost that the springs can't hold the valve shut (we are talking 45psi+).

The carbahn spec S2 motor is a very simple motor done right. Every other motor/setup has just blown up or never started in the first place. People get tied up to the hype and end up getting ripped off. The fact that even shop cars never really ran right is very telling.
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