DCR and Iron heads

Everybody talks about DCR for Aluminum heads, what about iron heads?

the material the heads are manufactured from will have a big effect on thier ability to disipate heat quickly from the combustion chamber,increasing compression tends to increase the heat generated durring combustion, aluminum transfers heat much faster than iron into the coolant, and its that factor more than most that forces you to reduce the effective compression slighly compared to an aluminum head IF your getting into the detonation range due to heat, of combustion, compression,and the ignition advance
the surface finnish and shape of the combustion chamber and piston dome,coolant temp. air temp,the combustion chambers tumble and swirl, the fuel octane, the quench/squish distance, spark plug heat range, also will effect your engines tendency to reach detonation
as a general rule on pump gas the temp in the combustion chamber is the limiting factor on reaching detonation.

http://www.chevytalk.org/fusionbb/showtopic.php?tid/92966/


short answer, aluminum tends to allow you to run about 1/2 point more effective compression, IE, if iron heads get into detonation at 10:1 ALUMINUM might ALLOW YOU TO RUN 10.3-10.4:1 BEFORE GETTING INTO DETONATION, BUT ON THE PLUS SIDE AT LEAST IN THEORY IRON HEADS AT ANY GIVEN CPR WILL HAVE A SLIGHT ADVANTAGE IN HP
but in my real world testing the differance is much closer almost non-existant
the main advantage I see in aluminum heads is lighter weight and thier much easier to repair when damaged

http://www.kennedysdynotune.com/Dynamic Compression Tech.htm

http://www.misterfixit.com/deton.htm

http://www.kb-silvolite.com/article.php?action=read&A_id=36

I expect you will find this interesting.

http://www.carcraft.com/techarticle...luminum_cylinder_heads_test/dyno_results.html