Help with compression!
Using your logic, I guess my setup is impossible.
stock LS1 bottom end
5.3 heads milled .025" by TEA (59cc actual volume), 2.02/1.55 valves
.040" Cometic gaskets
less than 2cc of valve relief
240/244 .609/.614 111 lsa cam.
That put me at about 11.6:1 compression. Actual measured p/v clearance is more than the typical "safe" recommendations of .080/.100"
Since you wanted to hear about results, well it sees 7k rpm quite often, and it's run flawlessly the past 3 years since I put it together.
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Using your logic, I guess my setup is impossible.
stock LS1 bottom end
5.3 heads milled .025" by TEA (59cc actual volume), 2.02/1.55 valves
.040" Cometic gaskets
less than 2cc of valve relief
240/244 .609/.614 111 lsa cam.
That put me at about 11.6:1 compression. Actual measured p/v clearance is more than the typical "safe" recommendations of .080/.100"
Since you wanted to hear about results, well it sees 7k rpm quite often, and it's run flawlessly the past 3 years since I put it together.

Without them, I'd have (-.010") p/v clearance. Minus, meaning interference, direct contact, no clearance at all. About the same as what you might predict.
With .100" deep notches cut into the pistons, I now have .090" p/v clearance. Since the notches were cut at the same angle as the valve, every .001" of depth cut is .001" of p/v clearance created. Funny how that works.


OP, sorry for the mini-hijack.
Without them, I'd have (-.010") p/v clearance. Minus, meaning interference, direct contact, no clearance at all. About the same as what you might predict.
With .100" deep notches cut into the pistons, I now have .090" p/v clearance. Since the notches were cut at the same angle as the valve, every .001" of depth cut is .001" of p/v clearance created. Funny how that works.


OP, sorry for the mini-hijack.

Without them, I'd have (-.010") p/v clearance. Minus, meaning interference, direct contact, no clearance at all. About the same as what you might predict.
With .100" deep notches cut into the pistons, I now have .090" p/v clearance. Since the notches were cut at the same angle as the valve, every .001" of depth cut is .001" of p/v clearance created. Funny how that works.


OP, sorry for the mini-hijack.

What is your deal? If you make a mistake in life, it is Ok to admit it. Continuing to argue about things we have done over and over again, does not add to your credibility or your intelligence.
Sit back and reflect on what you are saying, what more proof do you want?
1) 2cc piston relief
2) 6.125 rods
3) 3.905 bore
4) stock gasket
5) ten thousandth out of the hole
He didn't know exactly how much my stock heads where milled but said my CR is about 11 to 1. Hope this helps guys.
1) 2cc piston relief
2) 6.125 rods
3) 3.905 bore
4) stock gasket
5) ten thousandth out of the hole
He didn't know exactly how much my stock heads where milled but said my CR is about 11 to 1. Hope this helps guys.
64cc will be ~ 10.6:1


he must not have been loved as a child 