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Re: TT in T.O.
Wolff decided to speak these words:
>I read an artical about the 4 valve vs. 5 valve heads. More isn't always
>better. It comes down to whether the stroke is long or the motor is
>"over square". The Audi motors typically have smaller bores and longer
>strokes for good torque making the 4 valve a better choice. I don't
>recall the specifics, but that's the gist. A short stroke motor with
>wide pistons makes better use of the 5 valve technology. There is more
>space around the plug for valves.
I believe it is this that causes the Audi engines to be so good
turbocharged, especially the current ones. They dont produce all that
much torque down low when they are NA, but when they are turbocharged
with a small turbo, there is more torque and the already good HP.
One problem with this is the fact that Audi engines are very high when it
comes to feet per minute that the pistons travel. The engine in my car
is rated at about the same stress level as a formula 1 engine...i dunno,
i guess that is why the first mod when you are increasing the power in
these cars should be stronger rods, etc etc.....
Michael Sheridan Williams
1985 4000 S Quattro 185,000+ miles, Koni Yellows/Coilover (2B), strut
brace, Sport 8000 Tires, K&N, MOMO 4pt harnesses, Hella XL Driving lights
(excuse me, auxilliary low beams) (2x135w), magnecor wires....<out of
1986 Oceanic Blue, 4000CS Quattro--Parting Out(ask if you want anything)
My father's: 1986 4000 CS Quattro--Graphite 161,000 miles