piston valve clearance question
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From: Dyer, IN
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From: At the beach in little Rhody
Also, is that intake or exhaust?
Recommended minimums, as I recall, are 0.080" on intake and 0.100" on exhaust. You can get away a little tighter on the intake because the valve is chasing the piston but on the exhaust side the piston is chasing the valve so the valve spring is the only thing keeping the piston from catching up and taggin the valve. Hope this makes sense.
Recommended minimums, as I recall, are 0.080" on intake and 0.100" on exhaust. You can get away a little tighter on the intake because the valve is chasing the piston but on the exhaust side the piston is chasing the valve so the valve spring is the only thing keeping the piston from catching up and taggin the valve. Hope this makes sense.
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Burning Brakes
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From: scottsborro al
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From: At the beach in little Rhody
You mean this? Did you measure on your car yet, and if so, do you get the same numbers? This indicates that pistons in the motor that the measurement was taken have valve reliefs, which stock LS1 pistons do not have from the factory. I am getting confused on exactly what your measurements are in your motor and how you measured them.
"Comp's fourth most popular cam, the 277LR HR-113, idled at only 10.75 inches in our 6.0L test engine. With the stock GM LQ9 truck short-block and stock cast pistons with shallow valve reliefs, piston-to-valve clearance was right on the edge, only about 0.050 inch. That was enough to scrape by on the dyno, but we wouldn't want to rely on going that tight for real-world use...so you're looking at a set of custom, aftermarket, forged, deep-notch pistons to really make this setup run safely with about 0.080/0.100-inch intake/exhaust valve-to-piston clearance."
"Comp's fourth most popular cam, the 277LR HR-113, idled at only 10.75 inches in our 6.0L test engine. With the stock GM LQ9 truck short-block and stock cast pistons with shallow valve reliefs, piston-to-valve clearance was right on the edge, only about 0.050 inch. That was enough to scrape by on the dyno, but we wouldn't want to rely on going that tight for real-world use...so you're looking at a set of custom, aftermarket, forged, deep-notch pistons to really make this setup run safely with about 0.080/0.100-inch intake/exhaust valve-to-piston clearance."
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Tech Contributor
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From: Dyer, IN
Team Owner
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From: At the beach in little Rhody
Thread Starter
Burning Brakes
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From: scottsborro al
thanks for you input, thanks vettenut for the help,
Tech Contributor
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From: Dyer, IN
Seriously. Vettnutts is one of the few guys on this forum, that can tell you exactly how to set up the valve train....soup to nuts(or soup to vettenuts). All you have to do is give him detailed information, and answers his questions.
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