lt230s increased compression question...

[berryjo5]

hey guys, i just recently installed a wiseco piston that increases my compression from stock which is 9.0:1 to 10.5:1. I am wondering if i have to do any jetting work in the carb, if i should run any different plugs (colder or hotter than stock), what octane fuel you would recommend (im thinking 91 or higher), and also what would be the best way for breaking everything in...

im thinking some extra information might be useful before i fire this thing up

thanks for the help guys!

[MIKEL5469]

sup dude,haven't seen u on here in a while,i would think you would have to go up one jet size,and i would run the highest octane pump gas you con get anyways,the higher octane will help it run better,and you will get a more complete combustion burn

[berryjo5]

whats up mike! havent been on in awhile, been pretty busy lately lol... see i wasnt sure if i had to rejet because theoretically i am not adding any more fuel or air, i am just compressing the same amount alot more which made me think that maybe i dont need to rejet. Ill prolly throw some sunoco 94 octane in it today. the higher the octane the more resistant to detonation it is so i figured 94 is a safe start and i can always work my way down to say 93 or 91 octane.... any suggestions on what plugs to run or break in?

[jigolbeep]

you should need to run anything over 91 it would just be a waste of money... We all run JE 13.1 in our 250f dirtbikes and we only run 91

[DirtDemon]

You should be fine on premium pump gas, just use good gas. I imagine that motor would be good on pump gas up to about 11.5:1 or so. Depending on how the engine is built, more modern motors can run up around 13:1 before you really need high octane fuel, that is pretty much the limit though, many people run race gas or a mix of race and pump gas at that point.