How much would be left on the table?

metallidart said
If you were to run 1 5/8 headers on a w2 headed, big solid cammed, 10.7:1 422 cube small block, how much power would you be missing out on?

Also, what size would be optimum? 1 7/8?

i run TTI LA 1-7/8'' headers on my w2 436''. not ideal but all i had at the time and the money tree dried up!

made 653 hp and 590 tq.

maybe 5 hp is lost due to the headers.