ls6 heads
If you want, you can shoot those factory castings over to us and we can port them for you if you would like. It would be the same 220cc program that goes in our 5.3 head. Also, we can port the LS6 heads if you find a good deal on castings. You would only be looking at $650 for CNC work, CNC valvejob, Decking, and reassembly. 
We also have everything you need for a head install or heads cam if you decide to go that route! Let me know if you have any questions or concerns!
Jon
Texas Speed & Perf.
We also have everything you need for a head install or heads cam if you decide to go that route! Let me know if you have any questions or concerns!
Jon
Texas Speed & Perf.
its my understanding that stock ls1 heads flow around 235/240 cfm , stock ls6 are about 265 cfm. ported ls1 about 290/300cfm. same porting ls6 flow over 320cfm. my budget ls6 cast #243 TSP stage 1 flow 307 cfm at 600 lift. how much cash do you wish to spend? the cam makes the biggest difference. great heads with poor cam wont make big hp. if you only change heads dont expect more than 10 / 20 rwhp.
