That's right but there a few different heads, 4v 2v open chamber, boss 302 etc. The main reason why clevos have a rep for big power is the factory heads breath way better the factory windsors, with the canted valves etc. Windsor aftermarket heads are very good now, AFR and Trickflow, work very well, but with better low torque than a 4v clevo.
You'll more power than you need from a windsor, and all bitts are cheaper and pipes etc are easily purchased. Leave the clevos for the Xys and Mach 1s. I've got one in a XY GT faker.