Silvervette73

i am getting srtage 2E heads, already was going to have them mill it .03 for .5 point increase in compression. now i am going with the stealthII cam(.224/.220 .581 116 lsa) and i dont plan on going bigger with the cam. i wanted to know how much more can i have them mill the heads to increase compression. is it worth it? is there any more risk to it? and at what compression ratio will i have to stop using 93 octane. the heads are LS1 ported. thanks.

PREDATOR-Z

Use a thinner Cometic (.040 or .045) gasket to improve your quench and mill accordingly to get you a final 11.0>11.2:1 SCR.
MTI should do the calculation for you.
Tighter quench will improve flame travel and reduce detonation margin.

According to my calculator you need a 61cc chamber with a .040 gasket.
Or a .03402 mill. for a 11.1:1 SCR

Silvervette73

would the gaskets be just as good? i mean, does thinner gaskets make them less efficient or more prone to leaks? thanks

PREDATOR-Z

No, they are MLS. They require a very clean deck, that is all.

JZ'sTA

iTrader: (23)

The thinner gasket will be fine howeveer you wont get as much compression.
I would do exactly what PREDATOR-Z said as that is a very good combo. It will cost a little more because of the price of the gaskets but in the long run will give you some added HP and be the smarter way to do it.

Silvervette73

ok. i just got off the phone with MTI, they finished milling my heads the .03 and its shipped. so its too late for them to mill it anymore, but is it still worth getting the thinner gaskets? and if so, mow much do you guys think they will increase the compression ? and where is the best place to get them from? you guys are great, thanks for all the great info so far.

PREDATOR-Z

Yes it is still worth it, as they will tighten your quench, which gives you better flame travel, lessens detonation and increase your compression, therefore horsepower.
I have that cam BTW (Stealth II) and I'm getting a 62 CC (really close to yours) PRC 5.3L heads which I will be running with .040 Cometics.
You'll be close to 11.0:1 with your heads and .040 Cometics.

Silvervette73

thanks, i will get them. i guess stock comp ratio is 10.1-1 and with the heads milled, i will be at 10.6-1 and the .040 cometics will give me close to another .4? thats great! and it wont cause any clearance issues?
now, where do i get the .040 cometics? best place to buy from? thanks again.

PREDATOR-Z

No clearance issues with that cam.
Many sponsors carry them, Thunder Racing is having a Father day sale.