black smoke when wot?
06-29-2014, 11:26 AM
#1
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Car: 1986 camaro Sports Coupe
Engine: L31 350
Transmission: 89 700R4
Axle/Gears: 3.42 gov lock
black smoke when wot?
I noticed today when I was toying with a newer ram that when I go wot, I get black smoke out of my tail pipes. And a decent amount at that, I'm running a carbed 350 vortec with 2.5 stright pipe out the back. From what iv researched it could be from running to rich or from the fact I don't have cats and a muffler. Any suggestions on what the issue could be?
06-29-2014, 11:49 AM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: black smoke when wot?
black smoke = too much fuel or not enough air. Doesn't matter if you have an exhaust system or not.
Lean down the jets and try again.
Using a wideband o2 sensor, you should be in the 12.8 - 11.9 AF range which would put it about 13-19% rich when at WOT under load.
Lean down the jets and try again.
Using a wideband o2 sensor, you should be in the 12.8 - 11.9 AF range which would put it about 13-19% rich when at WOT under load.
06-29-2014, 12:04 PM
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Car: 1986 camaro Sports Coupe
Engine: L31 350
Transmission: 89 700R4
Axle/Gears: 3.42 gov lock
Re: black smoke when wot?
So I should re jet instead or trying the needles? What's the best way to tune without the wideband? Iv tried using a vacuum gauge at idle and reading the plugs.
06-29-2014, 01:34 PM
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Re: black smoke when wot?
Look at the inside of your tail pipes. Probably black now and sooty. Should be gray.
Secondary jets maybe too rich.
If Holley go down one size in secondary and see how it looks.
Secondary jets maybe too rich.
If Holley go down one size in secondary and see how it looks.
06-29-2014, 03:45 PM
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