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Re: 5 cyl. head mods/cam questions
> From: firstname.lastname@example.org
> To: email@example.com
> Subject: 5 cyl. head mods/cam questions
> Date: Monday, September 08, 1997 5:07 PM
> I think I just made a slight mistake on my exhaust system. My 84 4kq was
> for exhaust work anyway, but I might have went a bit big on it. I
> everything from the cat back with 2.5 inch piping leading into a single,
> chamber flowmaster. The sound is a bit loud, but my problem is I seemed
> have lost torque, especially in lower RPMs. I knew this was goin to
> as this is the case when we build and race VW's and put on larger piping
> free-flow mufflers.
This is very interesting. I Installed an exhaust from an ur q (thanks Ben)
on my 4kq. It is a bolt on accept for the rear exit at the valance. My
torque is up quite significantly (4-5%) at 2800-3500 rpm, and very down in
the 4000-4800 rpm range, above that it is way up. Go figure. I have had
the Schrick 272 for some time now and the torque curve was essentially flat
from 3000 to 5000 rpm with good power (after replacing a sick cat) up to
6000rpm. I suspect some harmonic (intake or exhaust) is causing the dead
spot in the 4000 rpm range. Overall though the car is quicker in spite of a
bi-modal torque curve.
> I had wanted to modify the cyl head anyway, as I have an extra one
> around. I'm hoping to bring back what I have lost due to the exhaust. I
> could tell you a dozen places to get decnet prices on VW performace
> but as far as Audi is concerned, I have no idea.
Be careful here... opening up the head will make low end torque worse. .
Increasing compression will help. As far as the Vw stuff goes, just think
of your JT motor as if it were from an '85 Jetta GL except it has a much
better exhaust system to start with. A 5 into 3 into 1 manifold /downpipe.
> I need to hear input from the list as to places that you found to be
> reasonably priced. I also need rec. on cams, nothing fancy though! It
> has to be compatable with stock CIS. Lastly, any idea's on what can be
> with the head while it's off. I'm certain I'm going to hear the same
> that we work with on VW's. NO I'm not going to put a turbo on it, so
> even suggest it ;)
My '87 will easily pull away from a stock '84 even though I give up the
weight and gearing advantage. BTDT. I estimate a sea level equivalent of
132 hp for my car at 5500 rpm.
> I just need another 10 -15 HP until I can build up the motor propely.
> E-mail firstname.lastname@example.org directly, THANX!!!