What timing setting has worked for you, to pass emissions?
#1
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Car: '91 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 2.73
What timing setting has worked for you, to pass emissions?
Hi Guys, having some trouble passing emissions. Now i've changed the cat, dizzy, plugs, and was still running a little bit rich and just slightly over on hydrocarbons..... so I think I was able to narrow the richness problem to the CTS and replaced that yesterday.
Everything seems to be ok now (as i cannot smell gas), but want to make extra sure i pass this time. Currently timing is set to 6, I have heard and read everywhere to retard timing to pass emissions.
So my question is how far do you guys retard the timing before going for emissions, would 4 do the trick, or go to 2 or 0 even?
cheers,
Everything seems to be ok now (as i cannot smell gas), but want to make extra sure i pass this time. Currently timing is set to 6, I have heard and read everywhere to retard timing to pass emissions.
So my question is how far do you guys retard the timing before going for emissions, would 4 do the trick, or go to 2 or 0 even?
cheers,
#2
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Re: What timing setting has worked for you, to pass emissions?
In CA, they check base timing as part of the visual. If it isn't set to specs = FAIL.
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Car: '91 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 2.73
Re: What timing setting has worked for you, to pass emissions?
Thanks for the reply paulo, i'm in Vancouver, Canada they don't check the timing up here. Any of the BC guys have any input on the timing. Im sure someone here has retarded timing to pass emissions....anyone?
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Car: '91 Z28
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 2.73
Re: What timing setting has worked for you, to pass emissions?
Bump....EGR also replaced, at timing 6 it was running real good and idles perfect. I went thru emissions at timing set to 0 just in care and just failed on hydrocarbons and CO. Would going any lower than 0 on timing make a difference or would it just be worse? or should i set at 6 and try? Nox is way within limits.
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Car: '91 GTA, '92 T/A Convertible
Engine: GTA: 350 w/Vortec heads, T/A: 305
Transmission: Pro-built 700R4
Axle/Gears: GTA: 3.27, T/A: 2.73
Re: What timing setting has worked for you, to pass emissions?
Stay at six. If it isn't passing at that point then something else is not working properly.
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