Best CDI rev box for 400ex?

[xk47]

I am searching for the best cdi box for my 2005 400ex, does anyone can help me, i saw bow that cost 40$ to 400$... the one at 400$ are programmable. I saw brands, but no dynotest no concrete specs of what they do. Thank you in advance.:)

[nosliw]

gt thunder is a good one.

[xk47]

it is pretty hard to find term like cdi and box i the search engine of this site. These CDI boxes looks all the same for me, it is not like car, like finding an ecu chip for a tdi volkswagen, different brand will give more power or make it reliable or more fuel efficient.

I'll search for a GT thunder and what it give.

My big question is, is it reliable at all? or i'll have problems like the dyna CDI guy that posted early....:huh

[nosliw]

some of them are made for the machine they are listed for and others are simply not. the ones that people have troubles with (white brothers for example) are just 250r rev boxes that will work with a 400ex, so they say they are for the 400ex. understand? technically yes, they do increase the rev limiter on the ex, but make it so the quad wont start when the battery isnt fully charged. im no expert on this, nor do i know what makes it do that but it does.

[wicked400man]

Ive had my quad since 01' with the whitebros CDI and never had trouble...im not saying it doesnt happen im just saying i never had any problems

[cals400ex]

look into a gt thunder box. he makes 2 different boxes. an aggressive curve and a mild curve. with any rev box you don't increase much power, you gain extra rpms. i probably wouldn't get one until you have a full pipe and a cam for sure.

I have the write bros rev box, and have started my quad with a nearly dead battery. I had to roll doun a hill and kick it in gear to get it to start, the battery would not event turn it over.