I believe they are the same lifters small block Chevys use. While Evos had problems with the rollers, the Twin Cams have been upgraded to better rollers on the lifters. A lot of us think the stock lifters in the Twin Cam are better than the aftermarket products, and I run them on fairly radical cams. A bud put JIMS in his hot rod twin cam and they were noisy right off, he replaced them with his old lifterrs and they are quiet with 56,000 miles.