Well guys I'm getting ready to port my heads, they are Dart/World S/R heads with the smaller 1.94/1.5 valves. Is it really worth it to install bigger valves in these heads? Right now my cam is only 203/212@.050 but I will be putting in a 230/236@.050 solid cam in there this summer. How much power increase would I see from going to the bigger valves(assuming I unshroud them on the chamber and open up the bowls slightly for them) vs. the same porting with the smaller valves? I'm not sure what would have to be done to install bigger valves, but approx. how much would it cost?(whats the "going rate"?)

And would the 2.02/1.6 valves from Comepetitionproducts.com for $80 work just as good as the $150 Manley ones?

I have a couple of examples that may help.
I gave my dad a 327 that ran 13.70's in my Chevelle with 1.94/1.5 cammal hups. He freshend up the motor; hone, rings, bearings and new S/R 2.02s with the same chamber size and ran 13.40's with a car that was heavier than my Chevelle. His current set-up is a 355/10.25 comp with a comp magnum 282 solid, the same heads(stock), rpm intake and 650dp. Its in a camaro that weighs about 3250 with driver, has a th350 with a 3000 stall and a 3.90 gear/28" slick. This car ran 12.40's in 50 degree air. Hope this helps a little.

definately go with the bigger valves