advice on heads

trudysduster said

This is what my guy quoted me for the $820:
bigger valves 2.02/1.60
Valve job
Decked
Bowls blended to the bigger valves
8 new valve guides
This guy owns a racing shop and builds engines for a living. he races a couple of dragsters. I have known him for years and he knows what he is doing. I was going to leave the smaller valves in as someone told me awhile back. they said it would be better for street use. But my shop guy told me the bigger valves would be better. I do not need to go aluminum. I am just looking to get more horses out of Tylers car. poor guy had a rice rocket blow his doors off on the interstate the other day and he is pissed. l

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That all sounds good but..... The engine guy is a drag racer, and this makes sense for racing. Take the heads you have, modded as described, and rev them to 3000-3500 and beyond with the low compression pistons that you have, put in a bigger cam yet, and then the torque and HP will start come on at the high RPM's. But the issue here is that this plan combines open chamber heads with a low compression bottom end, and the result is pretty predictably going to be an engine that is doggy still at the lower RPM's... which is where you spend most of your of time on the street. It is starting with a low static CR and then making the dynamic CR lower still with a larger cam.

So that is another reason to reccommend changing to closed chamber heads: get the CR up so that low compression bottom end that you have won't be such a low RPM dog. Being low CR to start with, it will very likely not matter if you use iron or aluminum, but getting that CR up is the point. The only way to get close to that with the present heads is to deck them quite a bit. Has he said how much of a head shave he is going to do for you? It's gonna have to be in the .060" range to get the combustion chambers down in the 60 cc range of combustion chamber size.

If not, expect a doggy low RPM engine, and then change rear gears and torque converter and all that to keep it revved it up all the time, and there goes your gas mileage, etc.....