texasTA

I have a set of LT4 heads and an LT4 intake manifold that I plan on throwing on my car in about three weeks when I do a cam swap. My question is what would be some advantageous things to do to these heads for optimum gains?
Obviously porting them, but what about a valve job?

How much can LT4 heads generally see with a really good porting job?

And does anyone know the stock LT4 valve sizes?

Thanks

Oh and my mods will be (in case that helps) 233/239 111lsa Combo cam, 7/16 CC Pro Mag 1.6s, Comp R lifters, hardened pushrods, EX 612 valve spring kit, fully built 4L60-E, SY3600 stall, 3.73 gears, 30# SVOs, Racetronix fuel pump kit, Hooker Longtubes, true duals, OVC wire setup, NGK TR55s, K&N FIPK, 1LE elbow and the LT4 heads/intake.

texasTA

Anyone?
I am trying to find out if a valve job would be good or not needed? Help

Injuneer

Stock LT4 valves: 2.00 intake; 1.55 exhaust.

You should be able to get them to flow 290cfm at 0.600+". I think GTP claimed over 300 on one of their ports (Stage 4?). You need to do a lot of work on the intake manifold as well, to get good numbers.

fstenuf

give loyde elliot(sp?) a call he does good work.

Ai

What should be done will depend upon what goals you have for the setup as well as your budget . Going through them, good valvejob, basic porting, possibly machinework to allow them to run higher quality parts in the future, using stock valves & with you supplying components could be done pretty cheaply & give you a package that should be capable of making 460-480flywheel with your setup I think. Of course if you wanted to spend $1300 or more, you can begin to get into a nicer set of heads, but it'll all depend on what you're after