Originally Posted by mopowers
Originally Posted by AndyF
Originally Posted by mopowers
Thanks for the ideas guys. As far as length goes, do you guys simply put the collector where you want it and connect the dots netting whatever length it takes (obviously within reason).

Are 2" primaries adequate for 600hp?


Depends if you're building dyno headers or car headers. For an early A body header you'll be lucky just to get four tubes into a collector regardless of length, size and number of bends. Those cars are horrible for headers. If you were building a set of dyno headers then 2 inch would be too big for 600 hp and the length is a critical dimension. For an early A body car all the theory goes out the window and you are just left with what you can fit into the car.


That's kinda what I was thinking. Space is definitely the limiting factor. With the inner fenders and torsion bars out of the way, it'll be a tad easier though. Do you think I'd be better off going with 1-7/8" primaries? I'm not going for every last hp.

Combo will likely be a pump gas 470 w/ standard port window Edelbrock RPM heads cnc'd by Modern cyl head, ~260-ish * @ .050" solid flat tappet.

I assumed 2" primaries would be an appropriate size. What do you think?


Measure the area of your exhaust port and go from there. I bet 1 3/4 will be big enough for that combo.