History: Gene Berg ent. (Head department,under Clyde Berg & Mick Wooten) I learned about quality and history.Great reliable set of heads. I wish i had the money to pay  Clyde do all my race motors!!! Performance Technology high performance cylinder heads. (Head department,under Fred Simpson & Mike) Some of the best sets of race heads that money can buy. I learned more about power and performance. what it takes to make the top numbers. Jeff Denhams This man has more work than the president. Some of the best sets of  street heads. Jeff helped me put it all together. Heads by:A.J.Sims Now I have my own head business. I try real hard to finish all my head orders within a reasonable timeframe. The best thing is to call me and ask for a timeframe. ( 714 )-639-4284 M-F 9am-6pm pst