New life for an old 340 (stock stroke)

Stroking always raises CR, all else being equal. Just looking at that tabulation of number on the SCAT website shows static CR's between 10 and 11. With a small cam like that, the dynamic CR may well work out too high.

Running some numbers quickly for that crank and piston setup.

• That kit with the ICON 741 pistons (which I think are what they are using)
• Typical J heads, not milled
• .039" thick head gaskets

Works out to a static CR of around 9.5, with a standard height block . Not as bad as I feared. Those pistons do not stick up out of the heads like stock hi-po 340 pistons did, so the lower piston height helps the keep the CR from rising.

Dynamic CR accounts for the cam size and ought to stay at or below 8.0 or so for iron heads to be able to stay away from detonation on premium pump fuel. A smaller Lunati Voodoo cam would be a 10200702, at 265 advertised intake duration, and .475 lift. Pretty easy to work with. dynamic CR would work out around 7.9-8.0. So that is as small as you would want to go on the cam. A very nice, torquey street engine at that; you would want to approach the tune-up carefully; I assume you are in CA near to sea level...yes???

And the nice thing about keeping the CR up is that you can go with a bigger cam and not hurt your low RPM torque.

BTW, with the heads you mention, you're not going to be stressing a stock cast crank, IMHO. They just are not going to flow the air.