Need some opinions

[lawmaster891]

hey guys im new here and have a 400ex and would like to get some more power. i was thinking either 440 kit or stroker. i already have cams, intake, and exhaust. what are your opinions on the best way to go. what is all needed for each and what is more reliable?

[live2surf]

i was wondering the same thing

[bigbad400]

if you want more power without sacraficing to much reliability go with hi compression 426. they rip. like 12.5:1. and run race gas. then all you would have to do is bore they thing to a 426 and throw the piston in there. if you want a straight beast you can get a 460 stroker, custom 440 piston with a stroker crank. but the answer is gonna depend on what kinda cash you want to play with and if you want reliable. i love the 426 in my race quad. i liked my old 440 motor too but the 426 ran right with it anyhow if not faster. but its a real well built 426.

[lawmaster891]

i was looking on ebay and found the 440 kits that come with cylinder je piston and gaskets for a little less then $400. are the 440's not reliable? if possible i want to stay away from race gas and keep running 93.

[slightlybent47]

Hi lawmaster891 and welcome to the site.

If you want to keep it dependable then don’t go over a 426, you can put a 11.5-1 and still run pump gas. Then you can P&P the head, and put a 450 carb on there and you will have a dependable and nice running ex. Stay away from the timing key and the rev box. Along with the mods you have, that will put you around 40 – 43 HP range.

Just my .02

[Wr3sTl3b0y]

hey i got the 440 kit new cylinder piston all that put in a while back didnt notice a huge difference dont have a ton of extras though looking at a stage 2 camshaft not sure if it will be a good buy or not? stock header lookin for a powerbomb with my white bro exhaust but i bet if i got the new clutch working right adjusted right then it will be better

[PaRedneckRiders]

never personally owned a 440 but have rode alot of 400s
a well built 426 will run with 440s all day and i own a 426 and love it (doing rebuild now)
imo the 440 runs a little hot if it was me i would run a four stroke tech secondary oil cooler with it
i have seen multiple ppl run 460s on the trails and with a 12:1 piston u can get away with running 93 alot of ppl will say u need to run race gas or like at least 100 octane
i personally wouldnt run race gas unless im running a 12.5:1 or higher comp piston
and if u really want a beast of a quad talk to four stroke tech about there 500 stroker kit
but it seems like to pushes the cylinder walls kinda thin and im not sure how reliable they r but they r fast
if u wanted to run a 460 u could go through lukes racing and by one for around 800-850 and it includes everything needed to build it