What will my compression ratio be? 416 LS3
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From: Mt Morris, Michigan
What will my compression ratio be? 416 LS3 K, Short block is being assembled now, my list of parts:
New LS3 block
6.125 forged rods & 4 inch crank
4.070 Wisecos, -3cc flat tops w/ valve reliefs, pistons actually have a slight dome to them to offset the valve reliefs, K464X7
cometic 4.080 head gaskets, .040 thick
GM GMPP CNC LS3 heads, 68 cc chambers
http://www.ebay.com/itm/Wiseco-K464X7-Piston-Kit-Chevy-LS-3cc-Dome-4-070-Bore-fit-Chevrolet-All-/311238766405?hash=item487746af45&vxp=mtrPiston listing says 11.4:1 w/ 68 cc chamber but it doesn't say what gasket is used to achieve that.
http://www.csgnetwork.com/compcalc.html
I used the ECR calculator & I come up with 11.57:1, but I have no clue what the piston deck clearance is as the short block isn't together. So I put .005 for clearance & that's what I came up with. I am trying to keep the CR at 11.5:1 & thought for sure I'd have to mill these heads but looks like I wont?
Thoughts? Thanks
New LS3 block
6.125 forged rods & 4 inch crank
4.070 Wisecos, -3cc flat tops w/ valve reliefs, pistons actually have a slight dome to them to offset the valve reliefs, K464X7
cometic 4.080 head gaskets, .040 thick
GM GMPP CNC LS3 heads, 68 cc chambers
http://www.ebay.com/itm/Wiseco-K464X7-Piston-Kit-Chevy-LS-3cc-Dome-4-070-Bore-fit-Chevrolet-All-/311238766405?hash=item487746af45&vxp=mtrPiston listing says 11.4:1 w/ 68 cc chamber but it doesn't say what gasket is used to achieve that.
http://www.csgnetwork.com/compcalc.html
I used the ECR calculator & I come up with 11.57:1, but I have no clue what the piston deck clearance is as the short block isn't together. So I put .005 for clearance & that's what I came up with. I am trying to keep the CR at 11.5:1 & thought for sure I'd have to mill these heads but looks like I wont?
Thoughts? Thanks
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Looks like I won't need to do any milling then! I've heard 12:1 can be done & run premium but 11.5-11.7 is right where I wanna be
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The cam will really determine how much scr you can run. As odd as that sounds. A cam with more over lap will lower DCR allowing more SCR. I am limited in my build to 11.5SCR because I'm running a smallish cam(.033" quench). 225/227 114. Makes my DCR about 8.95. A bigger cam could have allowed me to go up to 12.0 but I didn't want a bigger cam(yet). :-)
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Thread Starter
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From: Mt Morris, Michigan
Milling the heads .020 will help then?
BTR .660 lift duals w/ titanium retainers
BTR .660 lift duals w/ titanium retainers
. Mine has 22 degrees of overlap.....
I'd aim for 11.8:1.
Btw, the cam I'm looking at is pretty much exactly that. But as a Low Lash Solid Roller... 248/262 .705/.688 113+4... it works out to 243/257 113+4 .695/.678 with the lash taken out. If you can control the valve, it'll make power very high into the range.
Btw, the cam I'm looking at is pretty much exactly that. But as a Low Lash Solid Roller... 248/262 .705/.688 113+4... it works out to 243/257 113+4 .695/.678 with the lash taken out. If you can control the valve, it'll make power very high into the range.