Fly Cutting stock pistons
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Teching In
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Fly Cutting stock pistons Anyone know what the most you can safely cut a stock piston is? Drilled an old stock and you've got about 8mm of metal where the cutting is being done.... anyone who KNOWS for sure let me know! Please no guesses.... PLEASE
Launching!
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From: Freehold, NJ
I recall reading something about not cutting stock pistons due to the high location of the compression ring land. I may have read it in the LS1 performance book.. Maybe..
Eventhough you have 8mm thickness you need to measure the thickness between the top of the piston and the first ring land groove..
I'd also like to know why you would cut a stock piston? Why wouldn't you just put in a set of new pistons if going through all that work?
If you're looking to lower your compression you could use a different head gasket.. Is this gonna be a FI car?
Eventhough you have 8mm thickness you need to measure the thickness between the top of the piston and the first ring land groove..
I'd also like to know why you would cut a stock piston? Why wouldn't you just put in a set of new pistons if going through all that work?
If you're looking to lower your compression you could use a different head gasket.. Is this gonna be a FI car?
Lou at LG told me he has seen pistons cut .100 successfully 
, but, as Slowhawk said, .080 is the generally accepted maximum.
The reason to flycut factory pistons -vs- installing aftermarket pistons is ease and cost. It can be done with the shortblock in the car, and if done correctly and the correct amount, should not affect the piston's strength or longevity (unless large nitrous or boost is being used, in which case even a stock, unmodified piston would most likely fail). Also, is cheaper than installing new pistons, balancing, machine work, labor, etc. My pistons will be flycut about .070, fwiw (AS Stg 2.75, G5X3 on 112).
Shawn
, but, as Slowhawk said, .080 is the generally accepted maximum.The reason to flycut factory pistons -vs- installing aftermarket pistons is ease and cost. It can be done with the shortblock in the car, and if done correctly and the correct amount, should not affect the piston's strength or longevity (unless large nitrous or boost is being used, in which case even a stock, unmodified piston would most likely fail). Also, is cheaper than installing new pistons, balancing, machine work, labor, etc. My pistons will be flycut about .070, fwiw (AS Stg 2.75, G5X3 on 112).
Shawn
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Teching In
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Thanks for the info guys! I talked to a couple performance shops that are supporting vendors here and on the Corvette Forum and they all told me for my setup I would need a minimum .080, up to .10 - pretty much what you all have said. Thanks again! Happy Holidays
Dan
Dan
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Brett Foote My heads have a 2.04 (custom) intake valve, I am not sure on the CC of the valve relief....I may lose .1 of compression, but my heads were prepped/milled with this in mind, and my gaskets are .041 compressed (versus .060 stock), so, I should be good to go.....
Shawn
Shawn
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Originally Posted by Crazy C5 Cowboy
Anyone know what the most you can safely cut a stock piston is? Drilled an old stock and you've got about 8mm of metal where the cutting is being done.... anyone who KNOWS for sure let me know! Please no guesses.... PLEASE
joel
He got a killer deal on a set of JPR's heads that were milled .060, and is trying to run a cam with almost .600 lift and 230 degrees of duration.
We did a preliminary cut of around .065/ .035 into the pistons, clayed, and still had too close a fit. Looks like the reliefs are going to end up being around .125 on the intakes, It'll probably be fine.
We did a preliminary cut of around .065/ .035 into the pistons, clayed, and still had too close a fit. Looks like the reliefs are going to end up being around .125 on the intakes, It'll probably be fine.
