We just had a good discussion on this in the 6.4 section regarding poor filters altering pressure ratios. While filter minders are not a great tool to tune with, they can give you an idea of where you stand with inlet pressures. I believe Dustin and Mike Haller are building a setup to compare outlet pressure to inlet pressure to give the end see a better idea of how hard the turbo's are working and what things, like filters do to change the turbo speed. Etc.,
Eric Clausen was pulling filter minders closed with his S&B filter and high powers. Haller's dropped the air filter and picked up some decent horsepower. I know that's not really news as some of us drop our filters at the strip, dyno, etc., but when it comes to daily driving these big turbos, a bad filter changes alot, quick. The key is finding out what's happening number wise and what filter is gonna keep you in your desired pressure ratio. That all comes from testing, as you are about to did find out.
As far as collapsing goes, I'll have to see if I still have a pic of the inside of the filter. It actually pulled the paper from the mesh on the inside. It was a joke. Always was collapsing the minder and was replacing filters every oil change just to keep them clean and stay on the safe side. No matter what I did, a good hard pull under load would draw that minder everytime. Switch to the AFE system I have now and the KASB and I can draw the minder a tad but I've yet to pull it shut or eat the filter. I do know that PTSUPERD was eating AFE pro-guard filters with his 42r after a couple hard pulls and some road time. So it seems to change from setup to setup. Take Dillehay's truck for example, with high powers, intake manifold, and a S&B intake kit, lid on, he never had a problem. No filter minder light, an no collapsed filter. Now Eric's truck with the same manifold, turbo's and intake was closing the minder every pull even with the lid off. So it's different, all depends on the truck I guess. Maybe the driver even as well.
David, it's kinda a "filtering" too much deal but really thus because the filter media cannot physically allow the amount of air through that the turbo is asking for. I ran the same setup. I had some housing contact after a period of time. Not shaft play but still contact. Enough to dust the intake tract. That could be from a couple different things collectively though. If I was you, at the least I'd switch to a AFE big boost filter if not a n actual AFE intake kit like a stage 2
think I have pictures of the filter somewhere. I will look.