jets

[G Rincon]

i got a 400ex 03 model with a titanium 4 slipp on exhaust but not the headers (yet), a racing splitfire plug and a 14tooth gear i live below 3000 ft and i want to now what is the biggest jet i can put in without going to stage two and not taking my airfilter box lid off and not lmissing?

[JOEX]

I'd say a 152 or 155 should be fine. (Keihin jets)
From what I hear don't get the header unless you have some motor work done, it isn't worth it.

Joe