Page 1 of 1

One of my options

Posted: June 10th, 2008, 9:23 am
by dwg86
When I started planning my stroker build, I was looking at a budget stroker and the kb pistons weren't on the drawing table yet. So this was my plan and I still might go with it.
Cp802 pistons (1.592 comp distance)
258 (5.875 rod)
7120 head (increased combustion chamber 61.4cc, sbc stainless valves)
12 weight crank
Four wheeler magazine did a 4.6 stroker write up. They said they measured the 802 pistons and calculated the ring land groove and came up with total piston cc @ 18.8cc. Using KB's piston calculator I come up with static compression ratio @ 9.588. Using 61cc head, 18.8 piston head volume, .043 gasket thickness, 4.0 gasket bore, 3.905 cylinder bore, 3.895 stroke, .002 deck clearance for a total quench of .045.
DCR= 8.73 using the cam specs for the crane 901 cam (although I WILL NOT use a crane cam) I just wanted to see what dcr I might have.
I can lower the comp ratio a little if I open the quench a little.
Comments?

Re: One of my options

Posted: June 10th, 2008, 9:45 am
by Flash
On thing that i would do before you buy anything is have you deck hight check so you no exactly what yours is, and then replug the numbers in.
There might be quite a variation between blocks..................

at .045 quench you shouldn't have a problem with that compression.

Flash

Re: One of my options

Posted: June 10th, 2008, 9:53 am
by dwg86
The block will be decked to piston .002 below the deck with .043 head gasket.

Re: One of my options

Posted: June 10th, 2008, 10:00 am
by gradon
Yeah I didn't measure the deck height, but after the supposed .030" decking which should've left the piston .0085" below deck, my piston was actually .0105" below deck, so I could attribute that to the variance in the block. I now use .028" for the amount decked(for the calc).