A buddy will be porting them for me. He knows what he's doing and he advised me to get bigger valves for extra hp/tq. It'll be an extra $260 for the valve job. Is it worth it? Should I just stick to the porting of the heads and intake?
+1 to blksn. GT40 heads respond extremely well to valve jobs. On stock GT40's, a nice set of valves and a valve job is worth at least 15-20whp and even more torque.
BTW my worked GT40's are still up for grabs. For the money ur gonna spend on port work, valves and valve job, etc you'd be paying about the same for these which have much more extensive work done unless your buddy is cutting you a good deal. Take it easy.
I guess that sounds about right. My machinist charges $12 per cylinder for the valve job + expense of new valves. Then to get the heads milled was $32 each. And assembly with valve stem seals and checked/shimmed springs was $60. Then they paint them before handing them over.
But a valve job is a must when porting and re-building your head. Although it doesn't do some much for high lift, it gives you a really nice low-lift flow boost which will translate to more torque.