I was wondering how much of a gain will i get if i switched from shorty 1-5/8" primary to long tubes 1-3/4" or 1-7/8"?

I'm running a 383 forged with XE284 comp grind with 700 holley DP, Weiand stealth intake, 1" carb riser

Thanks, Chas

 

You most likely will pick up horsepower just by going from a 1 5/8 to a 1 3/4" primaries. Going to the long tubes will pick up your torque.

 

would i be better off getter some large primary shortys instead? with my motor setup im going to make more torque than hp so to even the 2 out i need more hp....

 

From the test I did and what others have observed with a good set of shorty headers such as what Dyno Don puts out there will not be much difference in horsepower from peak torque on up when compared to long tubes. Long tubes do better below peak torque. One of the problems is finding a good set of shorties.

 

Ya that is my dilemma. Im looking to make better higher rpm hp numbers because i have a lot of low end torque that i dont mind sacrificing.