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Project Shoehorn - M90 into a 4.0L

Thanks guys. If I shell out that kind of money I'll would be inclined to go for a standalone since I want the ability to change parameters down the road, and from what I understand the reprogrammed ECMs are essentially fixed. The other challenge is that I live in an area that requires emissions testing, so I have to tread carefully - the OBDII interface absolutely has to work.
 
SolarBell said:
Thanks guys. If I shell out that kind of money I'll would be inclined to go for a standalone since I want the ability to change parameters down the road, and from what I understand the reprogrammed ECMs are essentially fixed. The other challenge is that I live in an area that requires emissions testing, so I have to tread carefully - the OBDII interface absolutely has to work.
Click to expand...

I am installing a Haltech Elite in my MJ and it has OBDII support over CAN bus.
http://files.haltech.com/downloads/ESP/Elite_Can_Communications_OBDII_Wiring_Information.pdf
 
Figure out my issue with the FIC software so I'm connected and ready to rock. Stupid Windows OS issue, there's a reason I live on a Mac most of the time.

The Haltech Elite stuff looks really sweet, but I'm not ready to drop that kind of money right now.
 
The Windows install I was using was on a repurposed laptop that had been part of a domain. As far as I can tell, some of the security controls were left in place when it was removed from the domain. This caused the application to fail to even start. Once the application started I had no issue getting it to communicate to the FIC hardware.

I'm pretty confident I know what to do for the tuning at this point. The FIC doesn't need to do much, it's not like the multi-point tuning on the high-end aftermarket ECMs.
 
It runs! It needs tuning, but it idles well.

But I've run into the same issue I had before - the two elbows on either end of the main discharge pipe are collapsing under the idle vacuum. One option is to replace the elbows with aluminum elbows, but I've been unable to find replacement ones that have a tight enough bend. The other option that I've started on is to extract the wire from a 4" vacuum hose and to insert that into the elbows to keep them from collapsing.
 
The wire inserts worked - no more collapsing elbows. One down.

However I suppose it's time to bring up an old issue. I'm pretty certain my M90 is not pumping nearly the volume it's supposed to. According to this pressure estimating calculator, I should conservatively be getting around 12 PSI:

Blower Belt Ratio 2.3
Engine Vol. Efficiency, 80% (Modern Prod)
Blower Vol. Efficiency, 80% (Good_Old)
Engine Displacement (Liters) 4.0
Blower Displacement (Cubic_Inch) 90
Barometric Pressure (PSI) 12.2
Blower Boost 12.05 PSI

But in practice I'm only getting at most 6 PSI. I'm pretty certain it's due to internal damage in the blower - when I got it there was some gunk that had gotten pulled in, and the edges of the rotors were dinged and the housing scored in multiple places. I couldn't afford to replace it so I ran it anyway. I'm keeping my eye out now for a replacement that won't break the bank.
 
New M90's don't exist anymore. And even when they were made, Eaton never made a generic version, they only made them to OEM spec designed to fit in a specific engine. I am running an M90 manufactured between 1989 and 1992 for the Ford Thunderbird SC. It is the most generic and compact housing of all the M90's.

http://victorylibrary.com/supercharger/super-eaton-data.htm

If I were to do this again and had more money to do it with, I would probably buy a brand-new Whipple supercharger. Highly efficient, simple / compact packaging, lower thermal rise, and still in production.
 
Well, now I have to look at the supercharger for sure. Was warming it up tonight for tuning the FIC and it starting making all sorts of racket. I shut it down before it completely blew up. Time to pull it out and determine the damage.
 
I'll say this - the side-mount is substantially better than the older top mount but I still have non-trivial concerns with the design. But after years of trying to convince people what the issues are I gave up. No matter what, Boyle's law and the laws of thermodynamics are pretty fixed. And I strongly disagree with 7th injector designs. If you actually care to know what I think, read this entire thread then PM me.
 
Want to know what happens to a 25 year old supercharger when it sits for a while? The main rotor seal leaks and all of the oil ends up in the rotor chamber. The only way to fix it is a complete rebuild and the way to do it properly costs about $750. (This is because the gears have to be pressed off of the rotors to replace the seals and when everything is pressed back together the rotors have to be aligned to within 0.25 degrees and 0.003" tolerance. I don't have the jigs or tools for that level of precision.) And when a supercharger is spun to almost 12,000 RPM with no oil it doesn't do so well.
 
:(
Custom cars, custom problems.
Don't let it drag down the holiday - get after it in the new year and shoot some video of take-off.
 
If anyone is paying attention or interested, I have decided to gently rip this whole thing out and sell it. Just don't have the time or money to deal with it further. Will be posted for sale soon.
 
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