I've updated the title of this thread to be more specific as to what the thread now talks about and includes.
In an effort to ditch my C&L, I wanted to replace it with an LMAF. However after talking with decipha, it seems the LMAF has a larger inlet and outlet than the old GT MAFs had. Older GT MAFs, according to my quick-n-dirty measures, have an inlet diameter of 3.5" and an outlet of 3". An LMAF's output is at least 3.54" (90mm) and the inlet is closer to 4". So the LMAF isn't even close to a drop-in without some rigging.
So instead of going the LMAF route, he's recommending I go to a slot style MAF sensor and simply fabricate an intake track out of PVC or whatever I can find that'll work. Cut a hole in the side, slide the sensor into the pipe, and then figure out a MAF curve from there. That sounded doable enough, so I found the guy he buys used slot-style MAF sensors from on eBay and snatched one up for $21 shipped including a connector that plugs into the sensor.
So on to how I make that work. This is what I'm working with now:
That's a modified piece of mandrel bent 3" aluminum pipe from a Mustang CAI kit. As you can see, it's not quite a 90° angle. There wasn't enough room to maintain the full 90° turn, so I had to cut into the angle a bit to make it work.
If I don't mind a crease in the pipe, I think I could get a tighter angle from an exhaust shop bending up a piece of 3" exhaust pipe. However decipha dropped the idea of using PVC pipe to fabricate it up with just because it's a bit easier to work with. Giving that some serious thought, I got on the Internet and looked up what the standard dimensions are for PVC pipe. This is a website I found useful:PVC Pipe Size Dimensions, Identification & Pressure Ratings
It seems PVC is sized based on OD, not ID. A piece of 3" PVC is actually 3.5" OD which is the diameter I need for the cone filter to fit. Unfortunately, that's a bit big for the TB end. But the website also talks about using different size and grade PVC pipes to make telecoping reducers instead of using reducer fittings. Using their chart, should be able to get a piece of 2.5" pipe (2.875" OD) and slide that inside a piece of 3" schedule 80 (2.900" ID) to reduce it down right in front of the TB. And to keep as much flow capacity as possible, I'd want to get Class 200 (thin walled) 2.5" pipe which has 2.601" ID. The only X-factor is going to be how big the 90° PVC elbow will be and if it is going to interfere with anything. In theory, this is looking doable using PVC. But before I jumped, I thought I'd throw it out there to anybody else to comment.
I realize the joints inside of PVC pipe wouldn't be as smooth as a single piece of bent metal pipe, but I'm hoping I can deburr and put ramp-edges on all the pieces to smooth out the path as much as possible so there are minimal sharp edges in the flow. And yeah, the sharp bend of a typical PVC elbow isn't going to have as nice of a flow as mandrel-bent metal pipe. But I'm hoping this will still be an improvement, not a step backwards from the setup I've got.
If I can't manage to get the 3" pipe to work, the next option is to drop down to 2.5" PVC and telescope up to 3" at the filter.
Any reason not to go this route?
Or any thoughts an easier/cheaper alternative?
89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA