13.5 air fuel to lean?

[ebockus]

I did ulmer air box mod, exhaust mod and put a fuel controller on it. i have the bottom and top and wot perfect at 12.5-12.8 air fuel ratio. but at about quarter to half throttle i have a lean spot of 13.3-13.5 riding at 90-100km/hr. it starts at 8500 rpm like a switch. 8400rpm 12.8 then 8500 rpm 13.5. Every time. i maxed out the fuel on the controller mid range still 13.5ish. Like i said it quarter to half throttle. IS THIS TOO LEAN? PLEASE HELP LOL wide open throttle is mint at 12.5 so no worries there

 

[kuvasz]

that's fine!! if you went to the turbo/supercharge section you would have found your answer right away. quarter throttle 13.5 you won't blow your sled up, wot throttle maybe a different story. mpi states you should run a supercharged engine at 12.0-12.5 wot. i run mine at 11.2 because engines are $7000 to replace and fuel only cost $20 a gallon. i used to run my sled lean all the time and it was fast before the mpi, check my previous postings.

 

[ebockus]

Thanks. i tried search but i guess i need to look harder. thanks agian tho