"twk" > wrote in message
...
> In article >,
> twk > wrote:
>
>> In article >,
>> "biofilm" > wrote:
>>
>> > "twk" > wrote in message
>> > ...
>> > > Just a short story I'd like to share.
>> > >
>> > > I bought my SCT X3/XF3 tuner from a local shop near where I live.
>> > > They
>> > > will update my tuner for life. No problem there. A buddy of mine
>> > > loved
>> > > it and did the same thing, bought his from the same local shop.
>> > >
>> > > The friend of mine then bought a cold air intake from American Muscle
>> > > and they won't send him a tune for the CAI. He didn't buy the SCT
>> > > tuner
>> > > from them, so they won't send him the tune.
>> >
>> > hard to see why a tune "needs to know" if there is a cold air intake or
>> > not.
>> >
>> > after all, the air temp sensor has that nailed, also the maf.
>>
>> One thing I love about American Muscle, they have answers:
>> <http://www.americanmuscle.com/cai-faq-answer-popup.html>
>> <http://www.americanmuscle.com/why-tune-required-cai-popup.html>
>>
>> Crap, an incomplete example from AM. There is much more to it than that.
>> Well, maybe someone can provide a link to the following. I hope I get
>> this right:
>>
>> First off, all the CAI's I've looked at reuse your stock mass air flow
>> sensor.
>>
>> With an aftermarket free flowing intake path, your stock mass air flow
>> sensor can saturate, meaning more air will be flowing past it than it
>> can sense. This can cause a lean burn situation, damaging your engine. A
>> tune will "re-curve" the software controlling your MAF sensor and
>> prevent this from happening.
>>
>> Some aftermarket intakes are not much better than stock, but look good,
>> sound great, and don't require a tune. Some people like the looks and
>> new sound from those parts and that's fine for them. It's less expensive
>> too.
>>
>> But if you shop around you'll see some cold air intakes _require_ a tune
>> because they _will_ damage your engine by causing a lean burn condition
>> if you don't re-tune your car. You'll gain much more power from one of
>> these tune-required intakes too.
>
> Found a link from Ford Racing for the v6 intake. Others are similar.
> http://www.fordracingparts.com/parts...KeyField=11129
> It says, in BOLD type:
> Calibration is necessary to prevent engine damage! Calibration not
> included!
>
> Still not the link I saw not long ago, but you get the idea I hope.
>

Sounds right to me, airflow and MAF is fussy stuff, it may get fussy at low
temp or high temp.
stay away from lean !! more HP there but so is DET.

related: I remember some problems with how the air tube went to the MAF,
if there was sharp bend near it, the cal would be thrown off, also some
issue with the lenght of tube on both sides of the MAF, and inside the 1993
5.0 at least there is a screen that tends to strighten//smooth the airflow
out before it hits the MAF sensor. Some take the screen out, for more
airflow, but that makes the engine surge under some conditions.