does anybody have a clue as to what the stock compression ratio is on a 2002 Scrambler 400 2x4 2-stroke?i've been searching for days and cant find it anywhere. and would anybody know if there are any major consequences to shaving the head down in a CNC .010 - .020? thanks for any info. i do appreciate it.

-Matt

 

I don't know for sure but I would think it should be around 120 lbs or so. Shaving the head will help with bottom end power. With my wifes head shaved .020 the compression is 140 lbs.

 

what other things did you have to do after you shaved the head? like with the spark plug and what grade gas do you use?

 

By shaving the head .020 you will need to run 92 octane fuel. You can still use the stock plug.

 

do you think i'd run into any problems if i shaved the head .030? and will i have to re-jet the carb? i own a racing & performance shop so im not totally ignorant on what im doing.. i figure its basically the same principle as with a drag car... i was just making sure i wasnt gonna blow the thing up...

 

I think it's doable to shave it .030. You may have to run a higher octane fuel than premium pump gas. Just not sure what that will bump the compression to. You may call Rick at Rittercycle. I know he runs a stock race cut head on some race modded machines.618-644-3211. A super nice and helpful guy. I don't think you'll have to re-jet unless you go to an after market pipe or do some cylinder porting. If it's completely stock then I would say not cause they are really jetted pretty fat from the factory. I would do a plug check to be on the safe side though. Good luck.

 

ok, another question... is there one place you deal with for after market parts for polaris? or do you just search the web lookin for places? one more thing, did you paint the plastic on you and your wifes quads or is there a place you can buy those too?

 

yes,there are Hot Seat,HPD,RCR,and AAEN for the polaris and DYNOPORT,
all those are specialize in polaris performances parts and machining kit craft.
the head mod thing will work but an aftermarket head and o-rings offer an better cooling capacity wich help the 400 alot with mods,
anywhere from 140 to 150 on the PSI.

 

cool... thanks for the info...

 

Yeah like scramblered said those are really good places to get your aftermarket parts. No I didn't plaint out plastic. It's a graphics kit sold by graphicmx.com.