I know this is the race section, I thought it would be appropriate here.
I am actually starting to consider a 636 ~655" pump gas engine, maybe keeps the revs down to 6000 ~ 6500 tops. A nice street motor.

So.

I don't know which car yet or car weight. Probably a large M/T street type radial. In fact, probably need a 4.56 gear to go with the 2 overdrive ratios.

With the right clutch, which I know will be absolutely critical, do you think one of the stronger T56 varieties will live ???

I know you can break anything if you really try. But if you drive it with a little respect for the mechanicals, will a T56 be OK ???

I was looking at Lenco too. But I really like the T56. Lencos have their own quirks and requirements.