Piston to cylinder clearance
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Piston to cylinder clearance
hey...i need to know how much clearance to run on my pistons. im planning on running nearly 28-30psi, and i dont think 2 thousandths is enough...bc ive heard of guys running that and their motors ceasing up..would 3 thousandths be too much or not enough or wat? i need some input guys
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hey...i need to know how much clearance to run on my pistons. im planning on running nearly 28-30psi, and i dont think 2 thousandths is enough...bc ive heard of guys running that and their motors ceasing up..would 3 thousandths be too much or not enough or wat? i need some input guys
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What type of piston are you using? Compression, bore diameter, and Silicon content are key determining factors. If the piston is prone to expand and contract more, the clearances will increase. Your best bet is to use the piston to wall clearance specified by the manufacturer, and the formula for determining ring gap.
My CP pistons wall clearance was .003, and the ring gaps were .020 and .022 I believe which was equated from there ring gap formula, specifically for turbo applications. My bore was 81.5mm.
This is a good article about pistons if you want to read up and form your own opinion. http://www.team-integra.net/sections...?ArticleID=183
My CP pistons wall clearance was .003, and the ring gaps were .020 and .022 I believe which was equated from there ring gap formula, specifically for turbo applications. My bore was 81.5mm.
This is a good article about pistons if you want to read up and form your own opinion. http://www.team-integra.net/sections...?ArticleID=183
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um..theyre pistons from KMS at honda-performance.com...i believe the brand is supertech or something like that..theyre 9:1 cr with 84.5mm bore. the only reason im asking is because i talked to a guy who was running about 28psi and he locked up the bottom end...he said it was bc he didnt have enuf clearance under that much boost...i wasnt too sure about that so i figured id ask...it says on my piston specs paper the minimum clearance is .00315"
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The seller/manufacturer should specify the piston to wall clearance due to the differences in material expansion caused by different amounts of silicone used. High silicone content pistons expand much less than low silicone pistons.
I am going to guess that the pistons you purchased were low silicone, so you will need to run a larger piston to wall clearance to compensate for the expansion. Again, this information should be provided by the seller/manufacturer.
I am going to guess that the pistons you purchased were low silicone, so you will need to run a larger piston to wall clearance to compensate for the expansion. Again, this information should be provided by the seller/manufacturer.