Handleheld tuners and the wonderful California smog rules

Discussion in 'Forced Induction & Tuning' started by #BrownRoush, Oct 16, 2016.

  1. #BrownRoush

    #BrownRoush Member

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    Got a question for those that live in California. My car is an 01', so I just have the smog for me is just through the OBD2 port. I plan on upgrading my rear gearing to 3.73's, which will necessitate either a custom tune or a modification of the stock tune. I know a custom tune will fail the car smog wise.

    I'll try to explain this the best way possible. If I modify the stock tune, then just re-load the stock back up, will the smog shop be able to read/find out that I modified the stock tune? On my past cars, I have dealt with the whole "friendly" smog shop bs, and I just don't want to deal with it.
     
  2. lutter94

    lutter94 Well-Known Member

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    Throw a speed cal at it, that just modifies the speed signal, ecm won't know the difference.

    Sent from my SM-G930V using Tapatalk
     
  3. Mustanger

    Mustanger Well-Known Member

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    Why does the gear change require a tune? My OBDI didn't by any means...
     
  4. lutter94

    lutter94 Well-Known Member

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    It doesn't "require" a tune. But their ecm can be tuned to modify the speed signal to the gauges, I don't believe ours have that ability. I'm pretty sure if its new enough to have the ecm stored odometer, the ecm can modify the speed signal.
     
  5. Jakespeeds

    Jakespeeds Member

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    I am in Southern California and have to do the smog every 2 years. I use a BBK catless X pipe & catch in the engine compartment. The engine is a mild build and everything on the motor is BBK from the shorty headers to the MAF, throttle body and so on. I use a SCT for the programming. Full Throttle Kustoms in Fillmore did a full tune. On the handheld I have the stock tune and the aftermarket tune. Come smog time I install the factory mid-pipe, disconnect the catch can and hook up the factory tubes from the cam covers. I load the stock tune and it sails right through smog. Then I run it home and reinstall everything back. So far no issues.

    Jake
     
  6. #BrownRoush

    #BrownRoush Member

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    awesome, that's what I was hoping to hear