Originally Posted by Young Performance

The 088 is actually a pretty good head. It has a fairly large runner for a stock cast iron head at 325 cc. As you mentioned, the short side radius in the exhaust port is where they need help. With some work there, a little in the bowls and port matching, then I would think the above combo could get to 650 hp or better at 5800. The best bet depends on economics. If you already have the heads and all of the hardware, then spending some money on port work is not a bad idea. If you have to buy all of the hardware, and then pay someone to port them, then it doesn't make sense. The hardware for the stock iron heads and a set of aftermarket aluminum heads costs basically the same. So the parts are a wash. The amount you pay for the port work will cover a big chunk of the cost of the new heads. You are only out the difference between the port work and the bare aluminum heads. A full, complete port job could cost $1000+. A decent set of as cast bare heads can be bought for about $1500. So, you could have aluminum heads for $500 more than you were going to spend anyway.
You would have to do some serious port work to overcome not only the larger runners in the aluminum heads, but the increase in compression that the aluminum heads allow. That's where the biggest benefit comes in. You can get more aggressive all the way around. More compression, higher cylinder pressures, more timing, etc.....all because of the higher dissipation of heat. That same 540 can now make well over 700 hp. You will also should end up with an engine that is safer do to the lesser likelihood of detonation.
Hope this makes sense and helps.
Eddie

Originally Posted by MILD THUNDER

Great info. Thanks Eddie!