Back again with more questions on the 241 Hemi that had a burned head gasket. I have a number of spare cylinder heads for the 241 and 270 engine. I was thinking of putting the 270 heads on the 241 block. Will I gain anything? The issues i hear about concern the geometry of the rockers with the valve stem, the valves clearing the cylinder walls, header gasket thickness, effect on compression, and I'm sure many of you know of other issues.

Another thing I'd like to figure out; can someone track down the casting numbers i found on the heads to determine whether they are 241 or 270? One set of heads had #1554132 2 and 1554132 3, the other heads were 1828362 3.
If anyone can help, that would be great.