Hey everybody. I just had some motor mods done on my 400EX (11:1 piston, XR400 cam), and I was wondering if I need to invest in a bigger aftermarket header. Will the stock head pipe handle these mods? I would just like to know, because I want my machine to run to it's full potential with little restriction. Your help is greatly appreciated. Thanks.

 

It would probably have some more power if you added a white brothers header of fmf power bomb.

 

Anyone else have an opinion? I've looked at the FMF Powerbomb and the Hi-Flow header. I don't know if White Bros. makes a Works head pipe for my 400EX or not. Anyway, what do you guys think the about the FMF Powerbomb and Hi-Flow headers? Any helpful input is appreciated. Thanks.