Side Exit Headers

[hobby28]

I bought an older Harris modified chassis and it came with the old style side Exit headers. How much power gain will I be looking at by replacing them. Pretty standard SBC 9:1 compression.

[RCJ]

We had a 600hp motor on the dyno and it lost around 25hp with the old style short headers.I don't remember the torque, but we would switch to the shorty headers on a slick track.