is a 2.25 mandrel bent exhaust pipe big enough to make a 200 hp all motor gsr.

 

yes...however 2 1/2 inch flows better for the big cams, I think 2 1/4 is a little restrictive for 200whp all-motor. but can be done.

any cam the size of a JUN 3, or Toda C. needs a 2 1/2 inch exhaust, 2 1/2 inch test pipe, and 2 1/2 inch collector on a well designed header to achieve best results

but teken is right, it can be done