I have been making small changes to the avenger. Closed the gap on the plugs,went up in jet sizes,and changed the shift point to 7400. Last night went a 5.83 off the trailer to a new best of 1.20 sixty foot,at 120 for a 5.79 in the 1/8th. I believe when it is all tuned in we may see a 75 out of it. So far the heads have not givin any troubles with leaks or anything. After the first weekend out Brice called to see if I had any problems with the heads and even gave some advise to help with the top end miss. They may not be the best head out there but it is a good head for the average drag racer that doesn't want to have to look up a bunch of different parts.