I've been interested in the MST intake as well! Trying to confirm fuel trims as well as the filter size. I'd like to pick up an AEM Dryflow that will fit. But don't want another PRL situation where the velocity stack is sized oddly and no filters really fit well except for the included one.
And...
Stock tune and intake keep long term trims very close to 0. Usually in the negatives but +-2 or tighter. As you probably know, short term fuel trims fluctuate a lot more.
With PRL HVI long term trims are a bit more loose on the positive side +3 or so, but short term trims seem to be a bit...
TF-9007D is ever so slightly too tall. To get the air box lid on you have to force it. It'll fit, but the lid rubs on the top of the filter.
This filter also caused erratic MAF readings for me. My fuel trims were all over the place and at one point the car kept dying right after startup with a...
Loosen the filter and rotate it 180°. Could be turbulent air coming through the filter and throwing off the MAF. It's unlikely, but an easy and free thing to try. I've had turbulent air flow coming through a filter cause the car to stall and throw that exact code. Swapped filters and it went away.
Hey I'm no expert either, I just like to tinker! Using the AP200 might be easiest since it's a Bluetooth scanner that you can read on your phone.
Add short term fuel trim bank 1 and long term fuel trim bank 1 to live monitoring.
LTFT should be +-5 and STFT should be +-10 or so while driving but...
Here's the inside of the plastic EVAP elbow after using the PRL HVI/filter for the past few thousand miles. Might switch to the AEM to see if it's able to keep the intake tube cleaner.
If you have an OBD2 scanner, can you check short term and long term fuel trims with this intake? I'm curious how well the MAF housing is scaled to the ECU.
The pipercross filter has a metal mesh on the inside, so not sure if these ones break down or not like the older HKS ones.
Have you had any heat soak issues with the pipercross intake?
Picked one up this weekend for cheap off of Facebook marketplace. Any 6" flange cone filter will fit nice and snug on this intake. I went with the AEM Dryflow 21-2093dk as this is the one I had on my PRL HVI for a bit.
Took a mini 250 mile road trip with this intake and it performed flawlessly...