johnster

iTrader: (27)

my cam is 240/244 608/598 on 112 +4 58cc 5.3 heads 2.02/1.6 what heads gaskets can i ran,and be safe on 93 octane? .040 or .051

need in fo plz!!!!

plan on flycutting bout .080 stock ls1 block

LS1MCSS

iTrader: (18)

Your compression will be almost 12:1 with an .040 gasket. You would be better off with .051.

405HP_Z06

iTrader: (11)

Estimating that your flycuts will result in 1cc of cylinder volume, here are the calculations. The .052 calculation is based on the GM 6.0L MLS gasket, the .040 calculation is based on a Cometic gasket.

.040 Calculation:




.052 Calculation:



DCR numbers are NOT CORRECT, I DID NOT calculate IVC. Is that a Comp Cams grind?

johnster

iTrader: (27)

ya man its a comp cam

405HP_Z06

iTrader: (11)

That gives you a 74.5 IVC @ .006.

DCR calculates to: 11.73 SCR = 8.55 DCR

11.26 SCR = 8.22 DCR

Damian

iTrader: (89)

I would go with the .051 gasket. Even with .080 flycuts, you're gonna be close with that size cam and a 58cc chamber. ALWAYS check PTV when doing a setup like this, assuming things can cost you a motor or bare min a set of heads.

fauslpss

iTrader: (6)

Check PTV you might even be able to get away with less then that, leaving a little more strength in the piston. My personal clearance was 0.045 with a .056 gasket, 59cc on a stock exhaust valve with 242* of duration.

Eric

johnster

iTrader: (27)

i started cutting to day i was planing on only cutting the intake valves, well tps said i would be ok with the .040 gaskets even on a 100 shot, cents i was flycutting

what yall think? i going to check ptv

cabech984

iTrader: (11)

Are the .080" flycut measurements with or without headgaskets installed when you flycut?

johnster

iTrader: (27)

without head gaskets

Thimble

iTrader: (2)

I have 59cc 5.3 heads, 2.02 valves, 240/244 111 XE-R cam, with .040" gaskets. My comp calculated to 11.67 SCR, 8.77 DCR. It runs beautifully with no KR on 93 octane and no drastic cuts in timing.

I cut the pistons .100" deep to achieve .090" p/v clearance to the intake valve. (didn't have to cut for exhaust valves)

I don't think .080" flycut will get you enough clearance.

johnster

iTrader: (27)

how much clearance do u need to be safe?

405HP_Z06

iTrader: (11)

.080" Intake
.100" Exhaust

01FbTaWs6

iTrader: (12)

im running 58cc heads. 226/230 .609/.588 cam, stock MLS gaskets and I didnt have to flycut. My compression is 11.6:1 and my DCR is right at 8.9:1. I have to run 93 octane, 91 gives me KR if im ragging on it. I had atleast .110 on intake and exhaust for clearance. I stopped checking once I established I had atleast that much.

johnster

iTrader: (27)

got ya thanks 405hp z06

johnster

iTrader: (27)

ant it the other way around?

405HP_Z06

iTrader: (11)

No, what I posted is correct.

Damian

iTrader: (89)

Guys. Stop wasting your time worrying about useless formula's like DCR, and spend more time matching your combo together. IE: The heads/cam matching, valvetrain geometry, etc.

I've never once bothered with DCR, and never once have I built a weak engine.

405HP_Z06

iTrader: (11)

I agree, but no one is discussing it (DCR) in this thread. I post it if I know the cam specs because people on this website think its the be all/end all of engine specs. IMHO, its just another number.