thesoldier

I have a set of CNC'd 241 heads that will be milled down to 57cc. I know that's low but work has previously been done to the combustion chamber for improvements to take it down to a 63cc. Anyways I have a 230/238 .605 113+2 cam from AI currently. I'm going to check my piston to valve clearance with the clay method in the future but does this combo with the 57cc combustion chamber and the cam sound like I will be cutting it close and will need to flycut. I'm reading up on the flycutting process now and it seems simple enough. I hope I don't have to do it but want to be prepared since the block will still be in the car. Thanks for the help and guidance.

thesoldier

for anyone that would be trying something similar I used the clay method to check PTV clearance. I converted two of my hydraulic lifters into solid lifters. And after rotating the engine over twice i measured .071 on the intake side & .060 on the exhaust side. This was done without a gasket. I plan to use a .030 compressed thickness gasket so the intake will definitely clear but the exhaust is going to be .010 under I don't see this being drastic at all. But to the experts will such a small difference from the minimum be catastrophic? Any real life scenarios?

kevinsmachine

use good springs, clay method is the most accurate, piston can always outrun the valve if the spring gets lazy ,or you float the valves

kevinsmachine

i usually want a little extra room, sometimes it just doesn't always work out that way