I installed a Stillen POP charger intake, exhaust and JET EPROM and my butt dyno says I lost power. I will measure my new 0-60 times with my Gtech computer, but my questions is with regards to the new filter. The stock has 2 visbile sensors. On at the induction cowl, and the other after the filter. Question #1 is do they measure flow or temp? Question #2 is since the cowl sensor isn;t really measuring anything anymore (because the stock air box is now gone), is it detrimental to the EPROM data? i.e., will I get better performance with my stock box?

Yes the stock unit will provide more IF the temperature of the air going into the MAF is hotter [popcharger] as each 11F decreases the air density [weight in grams of O2] by 1%.

The oil soaked cotton may be slightly less restricive but even 22F hotter air negates all the improvement.

I've also heard terrible things about JET ecu's. Like they are just relabeled OEM ecu's. A JWT ecu is a much better bang for the buck. It actually does something

Yeah. I would love a JWT, but they don't make them for 97 on anymore.

The cost of reprogramming OBD2 makes them undoable for a limited market..............why you won't find anything that works after 1995 model year. Who would pay $3,000 for 10 HP or lb/ft vs $600 for 30 units improvement on a 90-95.

OBD2 while making it almost impossible to modify has split the difference [the factory needs to add less safety factor] since all sensors have 1 or more back up routines to the available power is usually 5% higher than with OBDI for the same engine........unfortunately the 97 lost cubic inches to improve fuel economy.

There is no secret [changeable] prom in OBD2! It is all calculated from the MAF voltage and various extra temperature sensors [air and fuel temperature].

Worse the O2 sensor are utilized even more to extend the rpm when closed loop is enforced!

The nice thing about OBD2 is that it will properly respond to more air [supercharging] without much fuss ........just add the air and the fuel will come up within reason and the timing will decrease as the air is added...........mostly bolt on up to 20-25% more air so 4 psi boost is easy from a ecu stand point. And a simple rising rate fuel regulator lets 5-6 psi occur.

1996 and 1997-2001 and the 2002 are pretty well stuck with what was built and effective mods are just not feaseable.

Thanks Qtech. My local tuner bud has a scanner for reading the OBD2 (On Board Diagnostics Level 2) codes, and they can be tricky to diagnose if you don't know what you are doing (such as myself). So, in a possibly related note, does the intake sensor that I see on the intake duct (that taps the air as it comes from outside of the hood) measure temperature or flow or Oxygen or? I ask this because I would imagine that it could confuse the computer if it is an important sensor reading. Stillen scanned my OBD2 after they installed the POP (which was also after the JET had been installed). So, I would hope that they adjusted what they could to get things to match, but you never know. I gotta keep them honest, so I am getting my second opinions. Man. I feel like I should be paying you for this advice. We should all hold a huge party for Qtech and the moderators...