flycutting dished lq4 pistons
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Teching In
Joined: Nov 2013
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From: lake wales FL.
flycutting dished lq4 pistons Spoke with Martin at Tick performance about a custom cam for my lq4 block/l92 head milled .030 build. he suggested a 223/238 112 cam or a 231/246 112 cam(requires fly cutting). Their is about a 25 hp difference in the 2 cams. So I searched the forum on how to flycut and I'm not to comfortable with doing it myself. Soo off to the local machine shops and was told about 125.00 which is not to bad of a price. But they asked me how much to flycut off the piston? What is a safe amount to flycut off the piston? Also I was told the crank will have to be rebalanced due to the change on the piston. Is that true?
Maybe Martin would be able to advise the depth of the flycut. But really in all honesty, it should be measured to be accurate. You really need to install atleast 1 piston and clay it with the cam to see if you are hitting, or if it just clears by how much. Then at that time you would be able to determine how much to flycut.
It could require a balance, but depends on how much material is removed. A piston needs to be checked before an after to see how much the weight is off. IMHO, if i know i'm gonna have to flycut, i will use an aftermarket piston with reliefs. If i don't wanna flycut a stock piston, i'll just run a cam that fits. I would use the other cam Martin recommended.
It could require a balance, but depends on how much material is removed. A piston needs to be checked before an after to see how much the weight is off. IMHO, if i know i'm gonna have to flycut, i will use an aftermarket piston with reliefs. If i don't wanna flycut a stock piston, i'll just run a cam that fits. I would use the other cam Martin recommended.
Last edited by Quick Ranger; Jan 29, 2014 at 03:11 AM.
The machine shop should be able to measure how much needs to be cut, but I can give you a "rough" estimate that would pretty much ensure adequate P to V.
I've never had a customer re-balance their rotating assembly after fly-cutting and we've never done it ourselves either. We have fly-cut our fair share of pistons in almost 12 years of business as well.
I can't see enough material being removed to warrant a re-balance.
I've never had a customer re-balance their rotating assembly after fly-cutting and we've never done it ourselves either. We have fly-cut our fair share of pistons in almost 12 years of business as well.
I can't see enough material being removed to warrant a re-balance.
