Ah he may not have assembled the heads BUT what could have caused it ?? Could be the assembly of r/ rockers etc ??Especailly that they replaced the rocker!! I'd check to see if there is any marks on the rocker arm where it may have made contact with valve retainer... Poping out the keepers-valve ???
Don't be afraid to try something new. Remember, amateurs built the Ark...Professionals built the Titanic!
Tuned & maintained by "Peppertree Perfmormance". Dart block, Scat 4340 steel crank, Custom C.P pistons.Oliver rods.. Mal Wood twin plate clutch.. Twin SC61/2's,482 rwkw/ 645 rwhp..
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