What is my compression?
What is my compression? I couldn't figure it out when I used the "compression calculator" thing. So that's why I'm asking here...
Shortblock has about 500 miles on it...
347ci
LS6 block
Polished crank
Ross 3.905 4cc relief pistons
Probe Ultralight 6.125" Forged I beam Rods-Doweled-ARP 7/16 Rod bolts
Diamond Rings Gapped @ .029 and .032
King Alecular Rod Bearings
Clevite 3/4 Groove Main Bearings
Clevite Cam Bearings
I'll probably reuse the Katech/CNC ported 241 heads with ARP hex bolts. Probably use a thicker head gasket (something over .050). I think I'll reuse my Comp Cam. It's mild. The specs I'm not sure (is there anyway to find out what they are???)... close to a 22x/22x, .581, 113 or 114 LSA. LS6 intake (I might switch to a FAST). Long tube headers, catted, & GMMG. Running through an m6 w/ stock 3.42 gears.
About how much compression would I be looking at? I'm looking to run a procharger at about 6 psi. Should I go with highly dished pistons or different heads? I know it would be wise & make more power with FI, but for the extra money is it worth it trying to lower compression a notch, for example like from 10.0:1 to a 9.0:1?
Shortblock has about 500 miles on it...
347ci
LS6 block
Polished crank
Ross 3.905 4cc relief pistons
Probe Ultralight 6.125" Forged I beam Rods-Doweled-ARP 7/16 Rod bolts
Diamond Rings Gapped @ .029 and .032
King Alecular Rod Bearings
Clevite 3/4 Groove Main Bearings
Clevite Cam Bearings
I'll probably reuse the Katech/CNC ported 241 heads with ARP hex bolts. Probably use a thicker head gasket (something over .050). I think I'll reuse my Comp Cam. It's mild. The specs I'm not sure (is there anyway to find out what they are???)... close to a 22x/22x, .581, 113 or 114 LSA. LS6 intake (I might switch to a FAST). Long tube headers, catted, & GMMG. Running through an m6 w/ stock 3.42 gears.
About how much compression would I be looking at? I'm looking to run a procharger at about 6 psi. Should I go with highly dished pistons or different heads? I know it would be wise & make more power with FI, but for the extra money is it worth it trying to lower compression a notch, for example like from 10.0:1 to a 9.0:1?
I'm getting around 10.2: 1 CR. I'm not sure what bore & CC's those ported Katech 241 heads are. I guessed 3.9 bore & 62 combustion chamber (I'm really not sure what the cc is on those heads?). I used a 0.052 head gasket thickness. I used a -4cc for the pistons. A 3.615 piston stroke. A 3.905 cylinder bore. Did I calculate this correct?
If I did, the CR is a little high from my goals. Any suggestions to lower it? Get more dished pistons... or heads with a bigger combustion chamber? I don't want it to be an expensive project to lower CR. Is it possible to run a 0.060" head gasket thickness with those heads? I know that won't help much but I was curious.
Which would be financially easier to do: swap heads and used stock LS6 heads, or different aftermarket heads, or just swap the pistons out.
If I did, the CR is a little high from my goals. Any suggestions to lower it? Get more dished pistons... or heads with a bigger combustion chamber? I don't want it to be an expensive project to lower CR. Is it possible to run a 0.060" head gasket thickness with those heads? I know that won't help much but I was curious.
Which would be financially easier to do: swap heads and used stock LS6 heads, or different aftermarket heads, or just swap the pistons out.
Last edited by candlelit; Sep 22, 2007 at 09:51 PM.
