L92 heads

[mean05]

Found 70cc on google, is that right?

yes

[fullthrottle]

If you check the gmpp website and view their catalog I think in the acrobat reader download, it will give you some info on those heads. As for milling I think I remember something about their deck being thinner. Anyone else know about that?

[bangbangskeetskeet]

Ok well I did a little more looking and ran some numbers.
From another thread...every .006" you mill that's about 1cc...so using that formula milling .020" would take away 3.3cc bringing the chamber to 66.7cc. Milling .030" takes 5cc bringing the chamber to 65cc.
Also I was looking for gasket thicknesses and found some say use .043" and some say .060" so too that into account also. Along with different piston selections...flat tops or dished (-8cc).

So here are the numbers:
Milled .000" w/ .060" gasket and flat tops = 10.19:1
Milled .000" w/ .043" gasket and flat tops = 10.61:1
Milled .000" w/ .060" gasket and -8cc = 9.39:1
Milled .000" w/ .043" gasket and -8cc = 9.73:1
Milled .020" w/ .060" gasket and flat tops = 10.58:1
Milled .020" w/ .043" gasket and flat tops = 11.03:1
Milled .020" w/ .060" gasket and -8cc = 9.7:1
Milled .020" w/ .043" gasket and -8cc = 10.07:1
Milled .030" w/ .060" gasket and flat tops = 10.79:1
Milled .030" w/ .043" gasket and flat tops = 11.26:1
Milled .030" w/ .060" gasket and -8cc = 9.87:1
Milled .030" w/ .043" gasket and -8cc = 10.26:1

That's a lot of typing on my iPhone.
Anyway back to my OP...we know with P&P the L92's out flow just about everything so what are the thoughts on these vs. 243 heads on a nitrous motor?