This is topic Tuning, Smog and Kommiefornia Silly in forum Tech Talk at Northern California Ford Owners  .

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Posted by ballisticxlr (Member # 14804) on :
Been out of the stang scene for 10 years. Used to have a couple heavily modded new edge GT's and now I'm starting over with an 02 GT that's got a 4v swap. Question is about tuning and the currrent state of CA smog. Apparently the test "detects" tuned cars and fails them. That's probably just detecting that something has been modified from the factory mapping or that some flag is set. I don't recall anywhere in the tune that one could even set an EO number or any flags in EEV IV that would get detected though so I suspect that this new "detecting" nonsense is actually only pertinent to EEV V ECU's. I used to tune my own with an SCT kit so I know how but it's been a lot of years . I'm curious about the smog thing... when I take it to get smogged I assume that as long as I have a CARB approved tuner (SCT makes CARB approved tuners) in my hand that whatever tune is on it is then made ok as long as it otherwise passes the sniffer. Can anyone here confirm/deny that this is the case or point me in the direction of some kind of authoritative source for this kind of info?

My 4v has FR500 cams and runs 11:1 compression through stock log manifolds and even a factory 4-cat 4-O2 sensor H-pipe. The idle is pretty well factory smooth, no real lope to it with those cams. I'm sure I could restore it to a factory tune and since a 2v ECU can run a 4v motor just fine.

And yes, I googled my little heart out but didn't find anything really helpful that wasn't the hand waving of people that didn't know anything about tuning.

Posted by BigBen (Member # 10594) on :
From what I understand is, they have carb approved tunes and if the files don’t match the carb approved ones it won’t pass
Posted by ballisticxlr (Member # 14804) on :
After a little more research which was a big PITA, it turns out they're checksumming the tune file contents against the tune ID. So, I can put a SCT tune on it and it should pass even if it's not perfect. Then I can pull the SCT tune off and put my dyno tune back on and get optimum performance. I might just register the damned thing in Florida or Kentucky since I can do either and if stopped, say, "I brought it out for a track day & photo shoot and I'll be taking it back next weekend."

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