[Jeff Lee]

I have a friend that raced a brand new 340 Demon in H/S starting in 1972. It was killer fast for the day, ran 11.90's. He constantly broke rockers. And that's a shaft rocker in case you didn't know. He admitted to "cheating" and using Direct Connection rockers to cure that problem. Now you can run Isky "High Ductile Iron" adjustable replacement rockers even though 340's never came with anything similar except for the 340-6 (T/A & AAR only).
Vic G. (see how I avoided that difficult last name) who runs one of, if not the fastest D/SA cars in the country with his '71 429 SCJ Mustangs told me he breaks rockers (average) of every 2-3 runs. Myself, while racing Stock with my '70 AMX found the ONLY way to stop the breakage was careful lash adjustments (hand turn the engine over, lash each rocker not just "wiggle" test) on every other run. These rockers are just not designed for high-dwell cams as SSD6 pointed out.
What plays on deaf ears here is the fact your front runners spend a lot of money trying to alleviate this problem. And they do. Price out BBC rockers that are offered that don't break? Not to far off the price of Jesel "Sportsman" series shaft racker conversion! So purists, tell me why you want $1400 forged rods & $800 Schubeck lifters and all that other stuff in the reciprocating assembly that is offered but not this?