Originally Posted by TomCat39
Side question for you experts:
Besides Piston To Valve Clearance. Is there any other issues with shaving a head past "service limit" (Honda Depth Marks)?
Will the head crack or worse?
I forget the exact numbers, it's in my notebook which I don't currently know the location of. But I think it was somewhere in the vicinity of:
for every 0.025" shaved off it retards the cams 1 cam degree (2 crank degrees).
the only issue I've run into with shaving PAST the service limit (0.075" on my head, currently at 0.080" removed) is PS pump alignment with the bracket. I had to drill one of the holes slightly larger in order to get the bolt to thread in without binding crooked. Basically meaning anything that bolts to both the head and block may need minor mods to the holes to still be capable of bolting up.
And as you mentioned; piston to valve clearance. With the simple fact of bringing the valves closer to the pistons, combined with the retarded valve timing, it caused my exhaust valves to start kissing the pistons at higher rpms at my current shaved level. I simply bought some gears and advanced the exhaust cam a couple degrees.