i got a hmf slip on, high comp piston and k&n on my 400ex and im putting a stage 1 hot cam in soon, once i get the cam in do you think that the stock header will still flow sufficiently?

also does any one know if hmf sells headers only, and if they bolt up to there slip on?

 

I have a 440 stroker. I have a White Bros. slip on muffler. I loaned the engine to a kid to race and he has a full FMF package. I don't know how much faster, or how much more power he had, but it was alot. It was on the same track and I ran 16/38 and he could get 16/36 to rev on the short track. That is a huge difference.

When I save enough pennies I am buying a complete exhaust system.

Check HMF's web site. I think they have complete exhaust systems. If they do you can get the pipe and run your muffler.

 

we were running a mild 10:1 406 motor with a stage 2 hotcam and we got substantial gains from a full hmf. we had a white brothers slip on with the welds grinded out of the stock header. the gains were really really noticable. it seemed as if the bike ran better with a stage 1 cam in until we got the full hmf setup.