Some tricks and treats this weekend.
First up, a neighbor has had two enormous Ficas-type trees in his yard for decades and never trimmed them. The thing about trees is that they can be ignored for years, but that always comes at a price. Early Saturday morning, a huge branch came down on his house and two cars. The roof on the house is visibly pushed in, one car had its side mirror removed and a large dent in the roof, and the second car had the branch come through the windshield in addition to dents on the roof and hood. A tree trimmer who sized up the situation several years ago said that trimming just one tree would be well north of $10,000 and refused to even bid. Because about half the branch landed in the street – city property – a city crew promptly arrived and removed that portion of it, leaving the poor owner with the branch still sitting on his roof. Did I mention it’s supposed to rain tomorrow? I drove by today and was surprised that he’s done nothing. I’d have at least bought a chainsaw and cleaned off the roof so a plastic sheet could be dropped onto it, but it’s his house…
The wastegate spring was lowered to 15 psi/200 kpa and more testing done. The MAP drop was back, big surprise, but this time, I heard something the instant power dropped from 200 kpa to 150 kpa; that’s never happened before. Removing the engine cover showed that the air filter element had been partially sucked onto the bell-mouthed intake. I wonder… could this have been it all along? Could it be the air filter element getting sucked onto the intake bell and reducing the filtration area by probably 80% and becoming a restriction?
As a quick test, the air filter was repositioned and another run performed. Again, the element got sucked off one edge and again, MAP dropped off. Next, the filter was removed completely, and guess what, not a single issue for the rest of the day. I even drove out to where some high-speed runs could be made to red line, and it worked just fine. Well isn’t that interesting.
The filter only recently started having one edge pulled off its mount, but the MAP issue has been happening for months. Full disclosure: I learned that I’m using the filter element upside down. That didn’t seem to matter at the time, but maybe it’s a big deal. There’s a screen mesh on one side of the filter – the top in my setup. It’s possible that without the support of the screen, the folder paper element can’t resist the suction and gets pulled onto the face of the inlet tube, becoming a blockage. What’s highly suspicious is that MAP always drops to 150 kpa, as it did today, which makes me suspect it’s the same failure mode each time. The only questionable part of this theory is that the filter doesn’t appear deformed like it’s been pulled away from the screen; the glue on the back is in good condition, but there is a dent from the inlet. Even so, I will add a support and see if this has been it all along. There’s a few ways to fix it, some easier than others. I’ll first try an easy way, running a rod or rib under the element to keep it up off the inlet bell.
What’s a little bothersome is that if that’s happening, I wonder about the fairly small air inlet on the scoop; could it be getting sucked shut? Looking at the air scoop, there’s two suspicious pale white marks along the top edge – I didn’t put them there and they didn’t used to be there. It’s almost like the plastic has been deformed. I’ll add a support brace to that as well, which will open up the inlet a bit more. I don’t want to get overly excited, but this is the first time something’s been found that is directly connected to the problem I’ve been chasing for months. We’ll see.
And finally, expect some Midlana news this week, so keep checking here, the Midlana forum, or Instagram 🙂