Trying to decide the best way to build up my short block. Car is a street car with occasional strip. Have been running the Lunati 00010 for a couple of years and have enjoyed the car tremendously, but looking for more out of it now.

Block has standard deck height and bore. Nothing wrong with the short block so a part of me want's to just drop a new cam in it. However, I've got it apart and it has cast pistons and crank. So I'd like to replace the entire rotating assembly and optimize the cam based on DCR and quench - but need to keep some $'s for a Tremac.

I'll top this off with my TFS TwistedWedge G1 heads, RPM manifold and 750cfm carb. 1 5/8" long tubes into dual 2 1/2" pipes. 5 speed with 3.73 gear.

355cid
XS268S, 268/274, .488/.500
5.7" rods, 9.2cc flat top, 0.015 shim gasket
DCR=8.199, quench=0.040

355cid
XS274S, 274/289, .501/.500
5.7" rods, 5.0cc flat top, 0.015 shim gasket
DCR=8.291, quench=0.040

383cid
XS282S, 282/290, .052/.500
6" rods, 9.2cc flat top, 0.015 shim gasket
DCR=8.323, quench=0.400

383cid
XS282S, 282/290, .052/.50
6" rods, 13.0cc inverted dome, 0.015 shim gasket
DCR=7.853, quench=0.40

Comments/recommendations please?

I wouldn't go below a 8.3 DCR with Al. heads.

I have a 383 vortec headed 6" rod, 7cc flat top, 280* cam for a DCR of 8.8. w/ cold air intake & 34* timing. I was tired of playing with the dist. and was already traction limited so I didn't try 36*.
It was fine with 108* weather.

Since it's apart, zero deck it and run an .040 gasket. The XS282S with flat tops is very close to my setup.

Thanks for the reply Scott.

This is the first time I've heard of being able to get away with higher than 8.3 DCR. I understand that aluminum heads disapate heat, which helps fight off detonation. So I assume the 7.7-8.3 rule of thumb is for iron heads.

What is the rule for alumnimum heads???

With a good chamber and a small block you can. I don't recall the chamber on a G1 head, but it has to be better than the old stock chamber. I know a few guys with BBC and 8.3 DCR that are having to tune them to get it to stop pinging. The smaller bore on a small block helps a lot. The big reason I think I get away with an 8.8 is my cold air intake. I have a camaro with a Z28 hood so it's easy. Just a $300 air cleaner housing away. :rolleyes:
I built my motor before I knew about Pat's calculator. Or I might have chicken out and went 8.5. A lot of people said it might not work.

I think Pat says add .5 for Al. heads. You can always retard the cam or put a bigger one in.

You may have to work at it a little to get it to not ping. If your not familiar with carb and dist tuning or don't want to, then you might go a little lower. I started at 10* initial and 30 total. And had some small vacuum leaks leaning it out at cruise. Ended up at 16* initial and 34 total.

quick question on the G1 heads..I was just reading on the net about them...they article said that any cam with more duration than 230º @ .050 would require piston valve relief work on the intake Have you had to do this?

Big Jim, haven't had to do anything with the Lunati 00010 that I've been running. this cam has 230* but only 0.480" lift. The goodwrench pistons have 4 small reliefs, but the deck has never been cut and the pistons sit 0.025 in the hole, there was a 0.039 gasket installed.

Haven't see the article you're referring to - can you post a link?

Big Jim?