jeting

i have a 2002 400ex just bought white bros e-searies pipe and k-n filter with pre filter and white bros rev limiter i need to now how many disk to use and what size jet i live in phoenix i think the altitude is around 1000ft above sea level

I had the same setup but with a vented airbox, put it on the dyno & the stock jetting was the best. That was with 15 discs, new it comes with 12, the more discs you add the mor top end you get. If you go over the 15 disc mark I would reccomend rejetting.
I live in vegas 2184 ft. altitude.
by the way this the first jetting post that mentioned altitude. It make huge differences. Take a look at the sigs in many of the posts & they list the jetting.

[Wheelie]

Run the E-Series with the 12 discs that it comes with.

If you're running your quad w/o an airbox lid, run a 40pj and a 155mj.

Good Luck

[RAPTORAZ]

Here's my combo:
2000 400EX
no airbox lid
168 main jet
45 pilot jet
needle moved up one notch
White Bros. filter
" " E-series slip-on pipe (18 discs)
" " rev box
Splitfire Triple Platinum plug
This bike runs within two bike lengths up Olds Hill against my buddies 440EX with an XR cam.
Putting in the 18 discs and rejetting with no airbox lid really woke it up. I didn't notice much of a power gain till I did that.