new parts..

[AtvRider21]

well im gunna get a drop in cam and a new piston and for the piston i want like an 11.1 or 12. etc.. whats the best... also how do i use race gas what do i do? plus how much power ill i get from these two and how hard will it be to install thanks peace..

[TRX_Thumper]

i suggest buying a clymer or haynes repair manual for the installation...with 11:1 compression you should be fine with pump gas...higher en that and you will need higher octane fuel...just find a place near by that sells it and run it 50/50 with 93 pump...or maybe 100% race fuel i dunno ive never fooled with comp that high and race gas

[AtvRider21]

k but if i get that and cam how much power would i get from it all and 93 octaine would work.

[y2k400ex]

Go to http://www.helminc.com they make the factory ones for Honda. The one for hte 400ex is $44 shipped

[TRX_Thumper]

yeah with the 11:1 comp u will be fine with 93...as for power increase im not sure but lots of 400 riders in here have done this maybe someone else will reply