big gun with k and n pipe jetting?

[HotRod2Fitty]

My buddy has a 400 and needs to know what jetting he should use. He has a big gun full system with a k&n filter.


Thanks
Matt

[400exbiggun]

well...with my mods people on here said a 158 main, but i still have yet to put that in
right now with only my mods, i have a 40 pilot and a 160dj main.
i have the biggun slipon--k&n--ground header welds--and it is a little rich. So if you are getting the dynojet kit, i say start at a 160 then go down from there until you get it right.
and i am gonna take the choke off after Rausch

[cals400ex]

in the summer a 152 to 155 and in the winter a 155 to 158 is what i say. my friend has a big gun silencer and and K and N and he runs a 152 year round. however, in the winter it is not quite as strong because its a little lean. these are keihin jets he is using. remember, bigger on the jets does not always mean better. if your a little too big, it could run like a terd.