I WANT TO MAKE EVERYONE AWARE OF INDY! Their customer service is lacking. I have had two different problems with them and ended up with the same results. The customer is left hold the bad goods. In July I order a rotating assembly and a set of Elderbrock Heads from Indy. Before the Motor was ever started we discovered one of the heads had a bad casting and allowed water to run in the motor on the Number 7 intake. They refuse to send me a new one. ( Motor never started) They did fix this one. After about fifty passes on the motor we decided to change intakes. While changing the intake we discovered a valve keeper in the valley. After further inspection the heads had more keepers broke and about to let lose on the valves. Luckly we caught it before it ate the motor. The vavle springs tested bad. ( 90 Ilbs @ the seat & 240-250 open) We have a solid lift cam 557 lift and shift @ 5,800- 6,000. Indy said the springs need to be replaced and and said it was the cam I'm running.Head are rated from Indy up to 600 lift. Buy with caution! I have gave them the chance to make this right with no luck. Thanks to Royce Thomason our heads for being done right. Have talked to them and sent two e-mail with no response. Talked to Jim and Russ at Indy with no results! Jim stated that I should of told him if I wanted my heads fixed?? Hey Jim that is what the phone calls and e-mails were about!