is there any aftermarket heads?

[cals400ex]

i have never heard of any aftermarket companies that make heads for atv's. you see them all over the place for cars. however, there will probally be a higher demand for heads on vehicles. all i ever hear about is porting/polishing for atv's. i was just wondering if anyone knew of any aftermarket heads for a 400ex?

[wheeltrax]

I have only seen aftermarket 2 stroke heads.. Havent seen any for 4 strokes..

[bigfoot300ex]

i think duncan racing makes one for the 400ex

[cals400ex]

i guess the next question is, are they worth it if one is made? possibly heat transfer might be better and maybe it is just a better design.

[pnut420]

Originally posted by cals400ex
i guess the next question is, are they worth it if one is made? possibly heat transfer might be better and maybe it is just a better design.

I think if you had a full blown stroker motor, with all the goodies, then an aftermarket head would be nice, but as far as heat transfer the best bet is to coat the piston, cylinder, etc. If you have your heads ported and they use a flow bench I dont see a different head design doing much. Also their are so many aftermarker exhausts (some are large tube headers, some are a little bigger than stock) it would be hard to design an aftermarket head they would be good with all of these, if you want to do it right they should take exhuast, etc. into consideration, then just port the head to match everything. Another reason you see alot of aftermarket heads on automobiles is because they are "aluminum" vs. the heavy cast iron heads, that can only support valves so big before you start getting into water jackets, etc, and the same goes for porting the intake and exhaust. Where with the 400ex you can put oversize valves in that should be plenty to get that thing flowing good, and then you can open up the exhaust and intake.