what main jet size should i run

[B 427]

i have a 2000 blaster has stock carb,fmf gold series sst pipe and power core2 sst silencer,k&n air filter still have air box lid on.has the oil injection blocked off i am mixing the oil at 32:1 ratio (amsoil).the main jet it has now is a 240 it also has a wiseco piston bored 20 over about what main jet should i run?

 

[stephen12091985]

thats sounds about right i think

 

['blanshee'man]

The fmf website says to run a 270 with the lid off, so start there and do a plug chop with few above and below

 

[stephen12091985]

but his lid is still on

 

[4cfed]

i ran no lid with a stock style filter, boyseen reeds .060 over vertex piston, fmf exhaust pre mixed and i ran a 270. but had to go to a 280 for hot weather