7140 06 Mustang GT

[fordstang2001]

background info - K&N Cold Air Intake, Kooks Headers, Catted X-pipe, and flowmaster mufflers... i just got my predator today, updated it to rev 36, and installed the 87 octane tune on my car to start... when i installed it, it said it is for use with the stock air box, so is it bad that i have a K&N Cold Air on it? or is that something i would need to get a custom tune for? to me those are just minor modifications.

also, what differences would i see if i used the 91 or 93 octane tunes as opposed to the 87 tune aside from my pockets emptying faster?

[mikel]

The K&N intake is designed to be used without any additional tuning, so it should be fine.
The 91/93 tunes have more aggresive timing curves, so they will provide a higher level of performance.

Thanks

[fordstang2001]

i probably should have mentioned this... but the reason i ask the question is that on Sunday my check engine light came on - this was prior to buying the diablosport - i took my vehicle into the shop, they told me it was a catalytic converter defficiency code which the guy blamed on "all of your mods" which i didn't think any were excessive. he also said that because of the modifications my engine computer was no longer calibrated properly for all of these modifications and i would need to have the vehicle retuned elsewhere and while i'm at it, i owed them 80 bucks for a diagnostic fee. so instead of having someone else do it, i figured i'd do it myself with your lovely product. i personally don't think ANY of those modifications should cause problems with the ecu, but what do i know, i only went to college for that crap... i now work construction but you get the point... at any rate, i'm sure your answer is still the same, but just thought i'd throw that additional information in there.

[mikel]

OK. These newer Mustangs are VERY sensitive to any improvements in airflow. Any CAI that improves airflow before the throttle body will generally cause lean codes to be thrown. The K&N generally does not improve the airflow to the point that it will throw codes.
Seeing that you say you are getting codes for catalyst system below efficiency threshold, I would imagine they are being caused by your high flow cats. As far as I know, the tunes in the Predator should block these codes from appearing.
If your check engine light comes on again, use the Predator to pull and clear the code, rather than pay $80 for a diagnostic service. Post the code # here and we will look into it for you.

Thanks