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How to Detune an engine?

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Old 09-29-2002, 11:35 AM
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How to Detune an engine?

Persay I needed to pass SMOG in California but still have a hardon for a huge built fast 350 crate motor. What can you do to detune them, so I can pass SMOG, then tune it back up again after? Or am I reaching to deep here?
Old 09-29-2002, 11:38 AM
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You could probably detune it real quick by handing the guy at the emissions center a 100 dollar bill. LOL!!!!!!!!!!
Old 09-29-2002, 03:53 PM
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Re: How to Detune an engine?

Originally posted by dunerida82
Persay I needed to pass SMOG in California but still have a hardon for a huge built fast 350 crate motor. What can you do to detune them, so I can pass SMOG, then tune it back up again after? Or am I reaching to deep here?
As a starting point, are all the visible parts OEM or smog exempt (they will have an exemption number)? The visual inspection might be your biggest hurdle.
Old 09-29-2002, 04:06 PM
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AMEN bad84z. :hail: :hail: :hail: :hail: :hail:
Old 09-29-2002, 04:54 PM
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Hey, maryland has some of the hardest emissions laws around. A mans gotta do what a mans gotta do.
Old 09-29-2002, 05:43 PM
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Lemme get a ahold of it. I'll knock the performance right off of that sucker!
Old 09-29-2002, 05:56 PM
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if your car is gonna be carb'ed, then before you go to inspection, retard the timing as much as you can and put really small jets in the carb... that is what i did and i passed emissions
Old 09-29-2002, 09:30 PM
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where would i find a list of all the states without smog laws?
Old 09-29-2002, 10:54 PM
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Originally posted by Rage13
where would i find a list of all the states without smog laws?
That would be the complement of those that do.
Old 09-30-2002, 12:40 AM
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not sure what kind of question that is. rather dumb from my point of view. all 50 states have smog laws, just not all have inspections. emissions laws are federal, not state by state. a state is allowed to be more difficult, but all still have it. i live in michigan where testing hasn't began yet, but the law still is in effect. as for detuning, just lean it out a bit and back the timing off about 2 degrees from where you'd normally have it. other than that, hope you weren't dumb enough to build something that wouldn't pass in your area.
Old 09-30-2002, 01:50 AM
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Here is a typical EPA webpage for I/M; this one is for Region III. You will need to determine the particular EPA Region of interest to you and then look at the links provided to the various state webpages.

http://www.epa.gov/reg3artd/vehiclet...ns_testing.htm
Old 09-30-2002, 03:10 AM
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Here's what ya do. Get another thirdgen that passed emissions, and pull that engine out and put it in your car. After you pass smog, you swap it back to the other car, then sell it to some sucker for more than you paid, and put your hot mill back in. Or maybe not. It must suck to have to deal with that crap.
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