Good day all! just wondering what your thoughts on the "rough" increase in HP would be from switching out original exhaust with a set of Hedman's would be on this 69 350? Keeping the existing duels, so just headers. BTW love the site!

 

Sorry guys, just realized I posted in the wrong forum, my bad..

 

This forum seems just fine. I would say anywhere from 10-25 HP depending on peripheral tuning & exhaust configuration.

Exhaust - 2 1/2" mandrel bent duals w/ xover or x-pipe should allow much better scavenging of exhaust.

Potential carb (more fuel to keep mixture ideal w/ better cylinder extraction) & timing adjustments (quicker advance curve) should help air throughput efficiency.

Regardless of the actual increase, you will feel a noticeable improvement as long as mixture doesn't get too lean & you don't pursue optimizing it.

 

I have and had them on my Cutlasses throughout the years and if you dont mind the work of putting them in go for it. Drivers side is rough. Do use a heat sheild or blanket to keep the starter cool because if I remember right its a pain to change once the headers are in. And if its old replace it when you do the headers. Personally I like stock exhaust. Less problems.

 

I installed headers on my 71 98. I don't know how much of a horsepower increase I gained but they look and sound cool. My "butt dyno" definitely approves.

 

Lol, thats all that really matters in the end isn't it !

 

not to mention it will sound a whole lot better