headers on 440

[69 buzz]

how much performance increase from headers on stock spec magnum 440? also performer rpm intake over stock cast iron intake... ball park

 

[SlinktRR]

it depends on a lot of things but I would say 5-10% increase. I added headers and intake to a '71 383 hp and it went from upper 200's to 330. Change to bigger carb and new cam and expect more. All depends on combination of parts used. Bottom line is you will feel the change.

 

[Cranky]

Performance parts compliment each other. A better exhaust system down stream will compliment the headers and so will a better intake and carb up stream. Now that you have all that, a cam will wake it up more. But, when doing all of this, even if you can only do one thing at a time, you should have a plan on what parts will work the best with each other. For example, you really don't want to use headers with huge primaries with stock heads and a small cam and carb etc. See where this is going? If I'm going to do just one thing at a time and the engine is going to stay fairly mild, I will install headers with better flowing mufflers (but I usually use straights) and bigger pipe then the intake and carb is usually next....