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[Kain]

It is 3 deg outside so i dressed like an Eskimo and went to start my Blazer. It fired right up and run like a big dog. It doesn't start that nice when it is warm out. my question is why? and it is -9 with wind chill.
It makes me wounder is it in the timing or what?

 

[Fastereddie]

Is it efi or carb?

 

[Kain]

Its a summit racing 750 carb hei distributor eddy heads, eddy cam, summit intake 350 bored 40 over timing is at 34 deg total time, wont be able to get my efi till march :-(

 

[b454rat]

low humidity

 

[Fastereddie]

It's probably running a little rich would be my first guess. The cold air is much more dense which leans out your mixture. What's your base timing? Vacuum advance hooked up to manifold vacuum or ported?
Good point on the humidity factor.

 

[Kain]

12 base it is hooked where it said to hook the dizzy vaccum in the carb instuctions

 

[Kain]

ya i need to hook the vacuum gauge back up to it and tune the carb

 

[Kain]

as soon as its not 34 deg im putting my msd on, i have all the parts

 

[Fastereddie]

Timing should be good. That's the Beauty of efi. Constantly compensating for air temp and pressure differences.

 

[Fastereddie]

The msd will help fire a slightly rich mixture for sure.

 

[Kain]

im hoping it helps with warm starts untill i can save my pennies again

 

[6872xtc]

What choke setup is on the carb?
If it has manual choke and it was mostly off, then yeah, it's rich.
Automatic choke, it sounds like it's doing the job well!

 

[Blue85]

Trucks do that when they like snow wheeling.