Hey, I recognize that rocker arm comparison photo! 'Course, they're my rockers... 
All this talk of strength concerns between T/A arms and 273 arms is completely unnecessary. In 1966, Dodge released the semi-infamous D/Dart, specifically for D-Stock NHRA racing. It's 275-horse 273 used a 284°/.500" lift solid-lifter camshaft, heavier valvesprings than any factory-built 340, and 4.86:1 rear gears. To say that engine was intended to have the tar beat out of it is a bit of an understatement.
Per Chrysler Technical Service Bulletin D66-HP-1:
So yeah... lore, legend, and what-someone-did-with-what-parts aside, Aunt Bessie's stock 273-2V mechanical rockers were apparently capable of taking an absolute pounding at the hands of RPM-crazy Stock-class racers with solid cams and silly gears that might miss a shift on their 4-speeds. The engineers that designed and specified all these engines seemed to think they were, anyhow. Just because they weren't used in E-bodies doesn't mean they aren't any good. They're infinitely better than any stamped rocker by an order of magnitude.
Ideally, I agree--the OP should find the right rocker if he can (and I realize this thread is rather old). If he can't, and wants to get moving, he can find an iron W2 exhaust or any 273 rocker and run with it. Nothing's going to break, and I've yet to see a show judge remove someone's valve cover.
Aftermarket? The only current aftermarket T/A rockers of which I'm aware are Harland Sharp, T&D, and maybe Jesel... open thine wallet wide. Then again, that's true of the OE and the old DC/MP/Crane parts at this point, isn't it?
All this talk of strength concerns between T/A arms and 273 arms is completely unnecessary. In 1966, Dodge released the semi-infamous D/Dart, specifically for D-Stock NHRA racing. It's 275-horse 273 used a 284°/.500" lift solid-lifter camshaft, heavier valvesprings than any factory-built 340, and 4.86:1 rear gears. To say that engine was intended to have the tar beat out of it is a bit of an understatement.
Per Chrysler Technical Service Bulletin D66-HP-1:
So yeah... lore, legend, and what-someone-did-with-what-parts aside, Aunt Bessie's stock 273-2V mechanical rockers were apparently capable of taking an absolute pounding at the hands of RPM-crazy Stock-class racers with solid cams and silly gears that might miss a shift on their 4-speeds. The engineers that designed and specified all these engines seemed to think they were, anyhow. Just because they weren't used in E-bodies doesn't mean they aren't any good. They're infinitely better than any stamped rocker by an order of magnitude.
Ideally, I agree--the OP should find the right rocker if he can (and I realize this thread is rather old). If he can't, and wants to get moving, he can find an iron W2 exhaust or any 273 rocker and run with it. Nothing's going to break, and I've yet to see a show judge remove someone's valve cover.
Aftermarket? The only current aftermarket T/A rockers of which I'm aware are Harland Sharp, T&D, and maybe Jesel... open thine wallet wide. Then again, that's true of the OE and the old DC/MP/Crane parts at this point, isn't it?
