hey ed, thanks for the response i guess i need to clear some things up. what i'm seeing when customer bring there bbc engines into be dynoed most of them aren't making power over 7500. i have built alot of bbc making power over that but most engine's being built are for the street and guys aren't looking for a high winding bbc. most are looking for 6000rpm big cid pump gas street engines. i agree with you 100% when it comes to all out race engine's and shift points for best et and mph. i have a very close friend at roush that does valve train testing and agrees with you about idle being very hard on valve train but differ greatly when it comes to the the danger zone of 6600-6900. he says that there are way to many veriables to make that claim. if the old big block had 1000hp and it's weight was 2980 with driver the car should have ran 160+mph it only takes 850hp to run 154 in a 2980#car. my mustang with a small block dynoed at 993hp ran 162 at 2950#. i did see that fulton has a 880cid that rev's to 8000rpm but built with very high dollor parts to live in this rpm and out of the price range of 99.9% of most racers.