The older leaded heads are slower burn tech but the newer heads are of fast burn technology with ulp versions. So you'll have to run with less timing/ advance curve..With out lead which slowed the burn some..
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..
Passengers, myocardial infarction material..