Originally Posted by nfreas313
Building a 454 bored over .60 with the eagle 468 internals with flat top pistons, The heads are Patriot Freedom series w/ 320cc intake runners and 119cc chamber and 2.25/1.88 valves with 1.7 rockers, intake is edelbrock victor jr. 454r port matched to the heads. My question is what cam would work best with this setup? I know someone who has one that they will sell me cheap, it is .715 lift 296/304 and 110 LSA, would this work well?
Your static compression ratio is less than 8.5:1, so no, that cam will not work. You have two choices, raise the SCR so you can run more cam or use a bone-stock cam in the motor as it is. Pistons with a ~25cc dome such as these from KB will yield a ~10.2:1 static compression ratio with ~118cc heads and you can use more cam.
You should always counsel with your favorite cam grinder for a recommendation, but I'll get you in the ballpark with this hydraulic roller....
With ~10.2:1 static compression ratio, that cam will yield an 8.357:1 dynamic compression ratio, towards the top of the range for pump gas.
If you are determined to use a solid roller, you may have to raise the static compression ratio even higher than 10.2:1. The first solid on the list in my Isky catalog requires 10.5:1 to 11.5:1 static compression ratio.
I'd set the squish at around 0.050" due to the larger bore and more piston rock on the wrist pin. Verify that the main bearing bores are round and parallel, machine as necessary. Register on the mains and cut the block decks according to the stack of parts you will use. The block is ~9.800" block deck height from the factory. If you were to use the pistons I linked (1.645" compression height) and stock 6.135" rods with a crank radius of 2.000" (half the stroke), then the stack adds up to (1.645" + 6.135" +2.000") 9.780", so cutting the block decks to 9.790" would leave the piston down in the bore 0.010" (0.010" piston deck height). Combining this 0.010" piston deck height with a conventional 0.040" compressed thickness gasket will yield a 0.050" squish. Bingo!
Any BBC gurus who reply can probably give you better info than I have.