The cams and lifters get worn out or destroyed because of the lifting arm (hope it“s the correct name for it) it makes to much resistance on both the lifters and cam that it gets worn out, wierd system.
My old one totally standard s2 with pace chargecooler and 2 1/2" exhaust, made 207bhp @ 14 psi
(holding from 2200rpm to the limiter) and was shit fast, still dont know why LOL
But have also experienced that you have to adjust the pully on the cam if using other then standard cam, and btw mine was @ 11deg WITH vacum on 98ron