Searched and Seached came up with some people who have done it but nothing showing a clear gain...well at least with the posts I found in my searches nobody posted back up.

Looking for more stock cube H/C bolt-on setups that switched from 1 3/4 headers to 1 7/8's, but whatever info you have would be welcomed.....

Thanks for your time

 

FLP Headers switched to Kook stepped netted us 20hp/25tq across the range on a 440rwhp car. Gained 3 tenths and 3mph consistant.

 

What did the rest of the exhaust consist of? Was it the same from the 1 3/4 to the stepped?

 

I gained about 10-15rwhp and tq going from pacesetters to Kooks 1 7/8s. (See post in this section). Went from 489 to 508rwhp=19 gain, but the 508rw had a shortbelt, so deduct about 4=15~