If I want to do ported heads, is it better to use LT4's (with intake) or LT1's? I know the ports are aligned differently? Is there anything that would give you more power with ported LT4's over ported LT1's?

 

Hmm... is it enough to justify the cost of buying those to get ported? I always see people with LT1's ported on here and not LT4's...

 

Depends on how far your willing to go, and how much you want to spend. The LT4 heads have a greater potential overall. If you just want a decent port job, have a budget, and your not someone who thinks 255cfm vs 256cfm makes any damn difference, then I would just get your LT1 heads done. You can still extract a lot of potential from them without spending a lot for the LT4 stuff.

 

Part of this is the port size too...

LT1 castings are going to be in the 200cc range when ported and a LT4 is 215-220cc. That's not bad if you want to turn some RPM with the motor and have a deep set of pockets for the LT4 castings.

A well done LT1 casting and a good valvetrain is probably the best place to spend the money. A LT1 head with new seats, guides and 2.02 or 2.05 valves with a good head porter will probably be enough for a good 350 motor. A 383 would like the LT4 heads better.

Bret