I'm wanting to upgrade my exhaust on my stock 502MPI.  I know that I'm not getting a lot on speed and HP gain just doing exhaust.  But it will be shedding quite a few pounds off the ass end, getting rid of stock manifolds and risers.  My question that I'm looking for advice on, is should I do headers, ie..Lighting Headers, or do something like a stainless marine, dana marine manifold system?  My engine is completely stock, should I worry about reversion with headers?  I want it to be reliable.  Thanks ya'll in advance for any input.

You're really not gaining much doing either. Are your manifolds in rough shape or something? Or is it all performance?

The reason why you would want to do headers is so that you can run a more aggressive cam without worry of reversion. On a stock engine you're not going to see any bang for the buck.

I think my starboard manifold/riser maybe done.  I have replaced the riser gasket, and it still leaks.  I understand no gains, besides weight reduction.  Plan on keeping it stock for the next year or so, then doing a rebuild ie.. heads, intake, whatever needs to be done on an EFI motor.  I have about 320 hours now on the the original block.  Just thinking further down the road.  Thanks for the reply Evan.

Okay, then if you're planning on down the road and you need to make a move...then do the headers.

It will allow you to have complete freedom on your engine decisions. You can be as crazy as you want with the engine build and in most cases, not worry about reversion.

I'd call Bob at Full Throttle, he'll set you up with a solid plan for the next couple years. He's very good at talking these plans through.

2nd on calling bob.

Headers would add a "little" power, freeing up the exhaust flow is always a good thing, but not your biggest gains to be had. Like Evan said, more of a complimentary mod. Cam, head work and headers would be your biggest gains. Maybe a 500efi intake setup. Not sure how restrictive the stock MPI manis are. Or there is always forced induction.