I am building a Chevy 350 specifically for cng. I have measured cyl chamber cc and calculated what I need to achieve 11 to 1 compression. I am using Keith Black pistons (should run cooler) with the top ring closer to the top of piston which I believe will help with the dry fuel.
Question -- In hyperutectic pistons, how much would you recommend increasing the piston to wall clearance for the added heat of combustion? The recommended clearance on this piston for gasoline is .001-.0025 and I usually go for a closer tolerence, I am thinking .003 (for the increased octane)for cng would be where I should go.
Anyone out there have suggestions, I would appreciate any help.
Is anyone interesetd in the "after" results? I have already published the 5 gas analysis & timing advance changes form the "before" results.
Stan M.
Question -- In hyperutectic pistons, how much would you recommend increasing the piston to wall clearance for the added heat of combustion? The recommended clearance on this piston for gasoline is .001-.0025 and I usually go for a closer tolerence, I am thinking .003 (for the increased octane)for cng would be where I should go.
Anyone out there have suggestions, I would appreciate any help.
Is anyone interesetd in the "after" results? I have already published the 5 gas analysis & timing advance changes form the "before" results.
Stan M.
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