View Full Version : wiseco 11:1 piston in a 500

03-02-2014, 11:18 AM
well previous owner overheated the utv and its smoked from the day i got it... well compared a rhino 450 piston to a stock hisun thanks to 231 motorsports and the pistons are damn near the same with the names being different so i ordered up an 11:1 piston and slapped it in yesterday and she works... was looking into doing a web cam swap but the 509 has a decompression setup... the only other way i belive to get it done is swap all 450 cam parts or see if they can weld/grind our cams... now my question to the dealers ... have the piston in cleaned/ported the head up ported the throttle body there is a huge hump in it that got me better throttle response... now i have an open unifilter big gun exhaust and the piston...... do i need more fuel? I have a wideband but yet to install it... guess i just need to do it and see where im at

03-02-2014, 01:23 PM
you are correct. dont know of anyone doing an 11.1 piston in a 500 yet. put that in and let us know where your at. i'd be curious to know. did you put your factory o2 back in the big gun exhaust or did you just get a slip on?

03-02-2014, 02:22 PM
Its the slip on so i have the factory exhaust which i might mod the pipes look crimpt not mandrel bent... i drove it yesterday and also added a shim and the sheave is machined it feels alot better but the rings i think were gone in the other