416 kit and 425 kit...

[AtvRider21]

How much h.p and top speed do these kits add.


416 kit

H.P=
Top Speed=


425 kit
H.P =
Top Speed=


thanks this is like the last post for a while so dont be mad..

I cant wait till i get my ex in 2-3 weeks when i get it ill post back and let yall know how it is well answere my question thanks... peace

[VegasEx'r]

They are both going to be very close in HP & top speed, but one huge factor is what cam you use. There isn't a "kit" you buy for either if these, but most people here talk about the "kit" as a piston & cam combo (& the misc. stuff like gaskets & seals are kind of assumed). What cam are you thinking of using, and what compression will the piston be? Then there is the pipe, jetting, etc.

I can tell you that my quad (see sig below) probably makes 34-36 HP (or maybe 1-2 more). The fastest it has gone with me on it (& I am a big guy at 260) is 73.5mph.

[AtvRider21]

How much money on mods did u spend on ure quad, can u beat stock raptors and banshees, and is the power reaallllly serious pull and strong

[GrounD PoundeR]

I've been thinking about putting a kit in my 400ex myself, and have ask people on Exriders plus several engine builders....Sparks & TC.....
You can increase alot of power before even cracking your engine open by adding a K&N kit or a combo where your carb can breath better. Put a couple holes in you air box lid. Make sure your carb is going wide open like its suppose to. After market exhaust, Spark plug, ignition key, raising the octain in your fuel. Before you crack the engine you probably should by a better carb or have the stock one modified....**** they have a drop in cam and 11:1 piston to go to before you even have to bore it. If you do crack the engine try to port and polish everything at the same time...

I'm learning too so if someone knows different let me know.

[RED121572]

Hey ground,

From what I know, your ideas are pretty good ones. Remember Dirtwheels or someother mag not long ago did carb comparisons for the EX? If I remember right, they stated that a bigger carb on a stock motor wasnt the way to go. I dont recall there reasons. Anyone else have any comments about this?

[GrounD PoundeR]

I know they did a comparison on a bored engine. Sorry I dont remember the size. As for you are saying well TCracing and Sparks will tell you different or at least they told me different. Modify your carb can be as easy a grinding, port and polish. Sparks does this for a pretty decent amount. I think around 150. I think for that much money you mise well buy one. The other thing your actually doing is prepping your engine for if you ever do get a kit put in.


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