What is the difference between 1.7RR from Big Block and 1.7RR from Small Block? Are those interchangeable???
Thanks

 

I wouldn't imagine they were interchangable, and the sbc ones are probably cheaper anyways.

 

I can have Big block version for $160...and all I found for SBC was over $250..

 

I'm sure the SBC rockers are much physically smaller

 

Correct! Ratio is the same, but the physical length is greater, for the BBC rocker.
Which means, the longer distance, from the pivot to the valve tip, will improve the geometry, of the rocker, through it's travel.

 

BBC are alot bigger. bigger push rod bigger head stud and the just bigger . they will not work