i dont like the 660 raptor.plenty of power bu threy are top heavy abd handle like chit!!!!but planty of power
displacement of a 400ex 24.2 cu-in
should heave a mod move this since it isnt worth anything truck wise
if its big enough for a 1.5 liter or bigger car, its too big for a quad. BUT.......a liter bike would ba able to spin it
raptors handle about as good as a lawn mower. good dune quads, lots of power to chug through the sand.
if you really want to have some fun id say go for it on the EX.....if it really cant spool it you may be able to fill weld the exhaust housing to increase the velocity in there. worst case, it doesnt spool, and you have no less power than what you started with! is the quad due for a rebuild? 470 stroker?
oiling should be easy, dont the 400ex's have an external supply line to the head? or you can tap a nipple into the filter cover.
what cam are you runnning in that thing? do you have a rev box? rpms will be key with a big turbo, and if you get even 1 psi of boost it will be SICK.
but im going 426 on it.it did have and will have a rev box again,thieves took that too.right now it has the stage 1 hot cam in it.HMF slip-on,drilled airbox,and uni air filter.it actually has an oil cooler so i could probably tap into that and have the return dump into the head like the cooler does.