aluminum vs iron heads

im thinking of putting bigger heads in my engine but i cant deside between getting iron or aluminum ones which one is better?  

Nine times out of ten the Aluminum ones are better.  
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The Silver Buick- '77 Skylark coupe w/ a Fuel Injected Buick 455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. Needing to replace a '69 Firebird 400.

http://www.bangshift.com/forum/index.php?topic=6189.0

http://www.carcraft.com/techarticles/ccrp_0602_iron_versus_aluminum_cylinder_heads_test/index.html

Most people say aluminum because there lighter and aluminum heads have higher detonation tolerances.
Be careful to not over heat them or they will be junk.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

yeah alluminum heads are usally better for wheight and power ( sometimes). overheating is huge problem tho. had much experience. steam coming out of dash of car and iron heads still worked fine. alluminums would b toast  

I would not say that aluminum heads make more power.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

yeah sorry both are about the same just aluminium can make faster. lighter weight. i like iron much better personally.  

actually i heard that in some cases indentical iron and aluminum heads the irons will make power. aluminum flex or something like that. same thing happens with the zl1 427 block i belive  

go with the aluminum. you wont over heat if your watch your temp. thats alot of weight off the front end of your car.  

the power gains on the cast heads are like 1 0r 2 horse on a 400hp motor the weight alone will make up for that.plus you can run higher compression on pump gas.and for the cost of getting the stock heads to flow like the aluminums it will equal out.chevy high performance took a short block 383 and got 2 sets of heads from a company where one was cast and the other was supposed to be an identical aluminum version and the aluminums still made 7 more horse because they flowed a little better out of the box and were supposed to be identical.  

yeah but if ur doing some serious beating iron will help. the weight savings are nice tho. iron if u beat them they usaually will come back for more  

Alum. generally are better suited for bigger springs and better flow. Not to mentions lighter. The real ? is... is your engine being hindered by Iron? I say its all about flow. The right Iron heads with some porting will do good but, Alum will do the same unless your ready to take them to the next level with a more agressive cam. Compression is a factor too. Is it a street rod or balls out racing machine that could use a little extra?

All new performance vehicles are using Alum. so, the engineeres are set on Alum. New school vs old school!

I vote Iron. Only cuase Im a broke fool that likes to go against the grain and not be flashy. Besides I would use the extra cash for porting, cam, valve covers and a practice tree to make up for the extra wieght.  

aluminum is better thats why their 3 times more expensive if your not retarded you wont overheat especially here in michigan where it rarely gets over 75 or so.  

Aluminum is only better for weight and they are not 3 times the price for alike heads.
Aluminum heads are not a good choice in my area.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

if you have to spend a bunch of money to machining the iron heads (bigger valves, hardened seats, porting), you could have the aluminum equivalant AND the weight savings for the same cash...

big feet...big shoes
big motor...big radiator
all the sudden we can all heat the water but can't cool it?  
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the red-headed step-child of the mailing list

fuzzy dice, air shocks & N50's rule

what are you saying pontiacman?
not good from a builders standpoint or from a tropical climate standpoint?  
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the red-headed step-child of the mailing list

fuzzy dice, air shocks & N50's rule