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View Full Version : BBC heads, aluminum vs iron?



caribbean20
08-14-2007, 07:05 AM
I have 2 cracked heads due to overheat (long story). Now in the market for replacement. Gen VI 502 block (casting 10237300) and the bad heads are Gen V cast iron (casting 14097088).
What are the pros and cons of aluminum vs iron on the heads? I have the roller cam with 580 lift, 240 duration, Vic Jr. air gap, Holley 850, EMI Thunder, MSD, Berk 12JG w/ plate, A/B mag/bronze, shoe, diverter spinning about 5,100 rpms in tight pump.
In my 20.5' Caribbean last saw 72.3 on GPS before mishap. The old heads have roller rockers/springs etc. matched to the cam. Looking to swap hardware to new heads.
I've searched and looks like some cheap Chinese stuff on market (Pro Comp?) for less than $1k. GM is quoting $1,500 for bare iron direct replacement.
Which way to go in my pedestrian lake boat, GM iron, Dart, off-brand aluminum? If I have to go to the hip, might as well add some H.P. Any opinions?

hotbo
08-14-2007, 07:19 AM
I have 2 cracked heads due to overheat (long story). Now in the market for replacement. Gen VI 502 block (casting 10237300) and the bad heads are Gen V cast iron (casting 14097088).
What are the pros and cons of aluminum vs iron on the heads? I have the roller cam with 580 lift, 240 duration, Vic Jr. air gap, Holley 850, EMI Thunder, MSD, Berk 12JG w/ plate, A/B mag/bronze, shoe, diverter spinning about 5,100 rpms in tight pump.
In my 20.5' Caribbean last saw 72.3 on GPS before mishap. The old heads have roller rockers/springs etc. matched to the cam. Looking to swap hardware to new heads.
I've searched and looks like some cheap Chinese stuff on market (Pro Comp?) for less than $1k. GM is quoting $1,500 for bare iron direct replacement.
Which way to go in my pedestrian lake boat, GM iron, Dart, off-brand aluminum? If I have to go to the hip, might as well add some H.P. Any opinions?
aluminum all the way.:D weight savings alone is a bunch.i have been running 2 sets of the procomps 1 set for 2 years now and 1 set for about 4 months on different boats.very happy with them alot of the peeps on here hate them and say they are junk b/c of a few stories they have herd or read.or b/c they are from overseas were everything else they have has some part of it made outside the us they just wont admit it or dont know they whole thruth.:idea:
you can run up to 1 more compression with aluminum heads than cast iron without detination worries:D they will cooler and more timing than cast iron,they are just a whole different world and so much better.i would not pay that much for cast when you can go alm.for not much more im sure that alot of peeps will help you out on this one and i wish you the best in whatever way you choose.remember the key to any good heads is the feller setting them up.i would double check any and everything someone else does no matter if you buy pro-comp,dart,brodix,edelbrock no matter have a nother head shop recheck everything they have done.i do this everytime we get heads done you will suprised what you can find,:jawdrop: later travis

IMPATIENT 1
08-14-2007, 07:35 AM
alum heads weigh 75lbs less than 990 cast heads;) that's reason enough:D

ck7684
08-14-2007, 09:50 AM
You can run higher compression because the alum soaks up more heat. Not the best for power because you want to keep the heat in the combustion chamber, however less weight is an advantage and you can overcome the comp issue by bumping it up. Polishing or coating the chambers can help also. This is usually a minor issue so dont get too worried about it. I think there are probly more perf options available in aluminum castings also. Alum is also easier to repair if something happens. I'm running Edelbrock heads that I got bare, but you might look into getting a complete set. That cam is really close to a Performer RPM cam. Their Marine heads come with Inconel exhaust valves too...