Head milling ?
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Head milling ?
Hi all I'm a newbe so if you could please take it easy on me just trying to figure this stuff out. I have a few questions to ask. First is how much can I get away with having milled off a set of 799 heads before worrying about ptv clearance and make sure my intake manifold still seals? What head gasket to run? And should I change my valve springs when I switch heads? And is there anything else that i should do to the car that i have not yet done. Thanks in advance for any help.
The car is a 98 t/a a4 with shift kit with 2800 stall. full exhaust true duals. I have double valve springs rated for .650 lift they have 15,000 miles on them. I did the trinion upgrade on my rocker. My cam is howard cams p/n 197715-10. Cai. 160 thermostat. trans cooler. And a fee things I can't think of
The car is a 98 t/a a4 with shift kit with 2800 stall. full exhaust true duals. I have double valve springs rated for .650 lift they have 15,000 miles on them. I did the trinion upgrade on my rocker. My cam is howard cams p/n 197715-10. Cai. 160 thermostat. trans cooler. And a fee things I can't think of
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Again, depends on current cam. But IIRC, the OEM piston with stock stroke come .005" out of the hole; so ideally, for optimal quench, you may want to opt for .040" gasket compressed thickness.
BTW.....stock gaskets have a compressed thickness in the neighborhood of .051", so going to a more optimal quest also results in a slight CR bump....and this may be more preferred in bumping CR than aggressively milling the heads .
When I go with an aftermarket cam, I tend to swap valve springs every 15k to 20k miles. But hell.....that's just me.
Also, you can always look at going with more gear.....like 3.42's or 3.73's.
Have fun!!
KW
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You can mill 0.050 (about an extra full point of compression) and get away with it as far as intake manifold but you must check your piston to valve clearance and this by the way is very easy to do.