I made a non roller into a roller and had no problems . I did use a small base circle cam I bought used and the motor ran very well with no problems . Custom cam grinds are surprizingly not much more than an off the shelf cam . I used stock rollers with a stck lifter retainer . The cam I used came out of a 347 , and I put it in a 306 . Tommy should be able to vouch for it . He knows the motor I'm talking about