Cdi

[2001 trx400ex]

here is my question, do i buy a cdi from white brothers or big gun which is only a 1 horse garentee with an agressive rev curve, or do i buy an unlimited rev cdi from http://www.MPHRacingltd.com which is a garenteed 4-5 horse and an umlimited rev?

[VegasEx'r]

Unless you have done some serious mods (like a 505 running straight nitro, etc.), I wouldn't waste the money. Check out GT Thunders test bench (http://www.geocities.com/gtthunder.geo/) to see how truly useless the aftermarket cdi is.

[NoWingNoPrayer]

Well i have the white brothers one and i love it. gave me about 7 mph and better low end.

as for the +4 i think that is just the spark timing maybe advancing in the low end and not givng it a overall peak hp but that same horsepower just sooner..
i would have to see a dyno

[hawiianpwr]

Get the MSD ignition its the only way to go

[2001 trx400ex]

i think i will go with the more promising mph racing one considering it is unlimited revs

Don't waste your money on a WB CDI..Junk..:macho