frey51

I dont know if its true, but I have heard that the different head castings produce different power...is that true? I have the 241 heads, but I know that there are at least 2 other casts out there for the ls1. Can anyone point me to any differences between these heads? I am pretty sure that arent any true tests between the castings, but anyones opinions and input are defiantly welcomed.

Fry

goober35

iTrader: (1)

241 heads are the best ls1 stock heads. If you are going to port them then it does not matter unless you have 243 (ls6) heads like i do (and know one will buy). The floor in the intake is raised and the exhaust is D shaped. The 317 castings do not have the raised floor to my knowlage.

ktmrider

I just read an article that mentions a specific casting mold that makes a 6-7 HP difference regardless of head type. Look for a triangular shaped indention around the bottom head bolt holes, those are the ones you want.