Reply to "Need a comparison between the C302b heads and Roush intake vs the Edelbrock aluminum heads and RPM Air Gap intake"

Steve,

It’s not in my car any more but I ran a hydro-roller cam of similar specs to yours except it was split duration and on 427CI. It had C302B heads that had minimal bowl work and essentially just the ports cleaned up so the CSA was very modest. For my tastes on that displacement, it was a very mild cam, but that was the intent. At the time, I just wanted a good running, reliable, street engine which it was and still is for that matter. According to the engine dyno it made 518HP @5250rpm and was nosing over from there on but more importantly, it was North of 500 ft-lbs from 3250-5250 rpm, idled, transitioned, and pulled very well in that range. The steel distributor gear on the steel cam looked like the day it was installed. That “temporary” power plant was a trouble free driver for almost 10 years. This was on the engine dyno with dyno mufflers whereas in my car it ran GTS cans. The engine was built to support much higher power and plan was to change cam at a later date but I drove it for a long time and still have the engine.

However, the above is not an apt comparison for your question of just a C302B head swap onto your short block since there is 20% more displacement. At your lower displacement, provided your Eddy heads could flow it, which could be a big if depending upon how they were worked, I would think peak power would occur at higher rpm, say +1000 rpm or so, and the torque figures would be more modest.

If you have stock dished pistons and standard stroke I would think you may have more like 9:1 CR unless the Eddy heads have smaller CCs which could have some performance impact as well. Ever had it on engine or chassis dyno?

Best,
K