emissions and ignition timing
Thread Starter
Teching In
Joined: Nov 2006
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emissions and ignition timing I failed the NOX portion of my emissions testing. 694 vs 4xx. I cleaned out the egr with some carb cleaner and suspect that my advanced ignition timing from the mail order tune might have something to do with it.
I dont want to pay for an update, so my plan was to use the timing retard function on my mallory 685 that I normally use for nitrous. I changed my nitrous activation switch to apply 12 v to the timing retard wire.
So I hooked everything up and wanted to test if it is indeed pulling timing. I turned the car on, flipped the switch, and didnt notice anything with 4 degrees pulled. I then set the box to retard 10 degrees and still, no noticeable difference.
What should timing retard feel like at idle/part throttle? Does the timing retard only kick in under wot? I need to pull the timing while at part throttle for the emissions test.
I dont want to pay for an update, so my plan was to use the timing retard function on my mallory 685 that I normally use for nitrous. I changed my nitrous activation switch to apply 12 v to the timing retard wire.
So I hooked everything up and wanted to test if it is indeed pulling timing. I turned the car on, flipped the switch, and didnt notice anything with 4 degrees pulled. I then set the box to retard 10 degrees and still, no noticeable difference.
What should timing retard feel like at idle/part throttle? Does the timing retard only kick in under wot? I need to pull the timing while at part throttle for the emissions test.
What mods are done to your car? What's your exhaust setup? I don't know that you are going to necessarily notice a difference with this timing thing unless you hook a scanner up to it to watch it. Also, I don't know much about emissions and testing, but if you retard timing only, won't there be more emissions from less spark to burn them up?
Thread Starter
Teching In
Joined: Nov 2006
Posts: 28
Likes: 0
Mods are mac mids/magnaflow high flow cats/magnaflow exhaust, cai, mail order tune. I think u are right.. probably wouldnt notice a difference at idle or part throttle from a few degrees of retard.
Originally Posted by dhdenney
What mods are done to your car? What's your exhaust setup? I don't know that you are going to necessarily notice a difference with this timing thing unless you hook a scanner up to it to watch it. Also, I don't know much about emissions and testing, but if you retard timing only, won't there be more emissions from less spark to burn them up?
you need to cork your exhaust more to get the egr to work properly.Macs are notorious for this problem.you could try to crutch the problem and throw some colder plugs in but your H Cs will go up.I do not know how well you passed there to see if you have any room.
that sucks I failed 5 times with my rebuilt motor in my 80 that's why someone out of state needs to pick it up I'm done with that crap that's also another reason why I really don't want to upgrade this engine freakin smog bs
