jetting carb

[greenone60]

i have a jetting ? when the weather gets hot do you go up(rich) on the jet sizes or do you go down(lean) and ideas. 1/8 mile drag car with sbc running 114 sunnco race fuel.single carb 850 holley hp

[wrightway]

Down

[curtisreed]

Down

X2

[chevyart]

what do you guys do with the timing in the real hot weather. up, down, or leave it as is ? thanks chevy art

[chevyfireball]

When the weather gets hot or the altitude goes up, the air gets worse so you can't burn as much fuel so you need smaller jets. I usually only alter the jetting two sizes.

I only alter the timing when the car is over powering the track (retard it 1 - 1 1/2 degrees. If I'm wanting to set her on kill I advance it 1 - 2 degrees. Just make sure you're checking your plug condition after each run to avoid detonation etc.

[JEFF69Z28]

over powering the track= spining the tires?

[chevyfireball]

over powering the track= spining the tires?
Yep. Some tracks aren't prepped that well. With a glide, convertor and nitrous motor there aren't too many options to get traction without losing too much power.

[Tod74]

I never mess with mine. I leave it the same all the time.











Of course I also lose in the first round most of the time too. :lol:

[cepx111]

I agree, hot/humid weather likes a leaner A/F ratio.

Jetting it down will aslo make it more consistent if you race where theres a temp drop from TT's to elims , E.G> daytime TT & nighttime racing.



I jet for consistency - not power/ET.\

Cp