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re: Head Work
>So far I have been told to go with over-size valves, brass valve guide
>?seals?, and a 90-91 10v cam.
On the valves, you basically have 3mm to play with before you have to
siamese the valves. I increased intake by 2mm and exhaust by 1mm. The
factory valve sizes on the Group B rally cars was something like 3mm
bigger on both intake and exhaust, so if you don't mind siamese valve
seats, I suppose you could go all out.
>Could I get some feedback on what works best:
> 1. What size oversize valves? Any reliability problems on valve seats?
> 2. What is the best cam to use that still has a reasonable idle?
> 3. Anything else recommended (port matching to intake/exhaust manifold,
> 4. Could someone recommend a shop, please.
1. See above
2. The shrick 272 if you've got a hydralic head, the 274 if you've got a
solid lifter head.
3. You can port the intake side of the head, but if you do that, you
need to match port the manifold. This is tough because you just
can't get all the way back to the beginning of the runner with a die
grinder because of the geometry. I did port my intake, but because
of the manifold geometry, I didn't get the whole thing. Not sure
of the effectiveness of this mod. Exhaust you should leave alone unless
you're willing to start getting into pulse converter design theory.
4. I had Fumio Fukaya Enterprises in Riverside, CA (714-784-1251) do
mine. He specializes in VW heads, but does Audi's as well. I can't
say that I recomend him, though, since I had to take my head off a
second time to correct some of his mistakes.