is there any difference
If thats all you have then use them otherwise the iron does weigh more and you will have to use the .026" head gaskets with them. If its stock it will be just fine but I would recommend going with aluminum.
The only difference as stated really is the weight and the fact that Alumin heads dissapate heat better/faster and that is why the Fbody's run a higher compression then the bbody (where the iron heads are found). If you are going to do some work to them alot of guys will say the iron heads flow better and will open up more, but I'd still stick with the aluminum heads even if you decide to have em' ported.
