extremeviper
Member
Have been instructed to unplug the carb float bowl vents from the air box and jet down. Anyone else doing this? suppose to get better MPG and more consistant jetting, went from a 165 with the carbs plugged in to a 155 unplugged 780 big bore, porting, pipes stock air box
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**sj**
Life Member
yes..you should do this to prevent lean condition due to vacuum on ventlines...therefore float bowl and therefore main jet at high velocities..
let them hang in the belly like sx or srx's
let them hang in the belly like sx or srx's
is this recomended for a viper with pipes to. Who all is running this way. I could run my stock jetting with pipes if this is true. Maxdlx

**sj**
Life Member
I' dont believe stock jetting...but much closer to maybe...making more power needs more fuel....it's much safer and more consistant....
10 sizes
I have done this and in my personal experience it was good for about 10 sized on the main jet i/e 165 down to a 155 and sometimes 150/150/152.5 if it's not below about 10 degrees. This was on a 780 BB. By the way this did absolutely nothing for my gas mileage.......or lack of.
Madmatt
I have done this and in my personal experience it was good for about 10 sized on the main jet i/e 165 down to a 155 and sometimes 150/150/152.5 if it's not below about 10 degrees. This was on a 780 BB. By the way this did absolutely nothing for my gas mileage.......or lack of.
Madmatt