Sprinter 4WD Conversion Idea, GMT-800 IFS.

luthj

Engineer In Residence

b dkw1

Observer
I talked with accutune, and they will revalve (or order different?) the fox gm 1500 units for me. I just need to call on monday.

Ryan is good to deal with and knows what he's doing. He should be able to set you up out of the box with valving and spring rate. Way easier than piecing it together yourself.
 

luthj

Engineer In Residence
Ryan is good to deal with and knows what he's doing. He should be able to set you up out of the box with valving and spring rate. Way easier than piecing it together yourself.

Yes, he appears to be very competent. Ideally I would like a bit higher spring rate, but only a handful for spring makers can fab a 3x14" spring over 700lb/in. I believe the 700lb unit will work for my application, but worst case I can swap later for ~250$
 

luthj

Engineer In Residence
I installed the FWB in the van. The front right WSS runs through the box, and I set the in/out ratio to 1:1. Success! No codes, normal operation. I had some trouble with it throwing a bad sensor code. It seems the ESP module will throw a code if the input voltage exceeds +3V (6V p-p). I modified the protection resistor on the uno output to produce 3V at the WSS+.

Obviously I need to evaluate if overtemp issues exist with my board. Some users report the voltage regulator on the uno will overheat if the ambient temps get too high. Such as idling in traffic. I need to tie up the wiring and secure the box. Then I can take a longer test drive. I didn't get on the highway, so my speed was limited to 55mph on this test run.


IMG_20190629_122128971
 

luthj

Engineer In Residence
Doing some detail work on the subframe. On the engine mount towers. Any thoughts if I need more boxing?

Currently I just have one brace on the outside.

524912

Nothing on the inside though. The back side is 1/4" the front side is 3/16 plate. Yes I know its heavier than needed (160lbs), but it is a prototype...

524911

I also got a bumpstop to measure. I was off a bit from my guesses. Its mostly solid rubber, so if needed I can trim the bump to fit better.

IMG_20190627_164109144
 

Len.Barron

Observer
Doing some detail work on the subframe. On the engine mount towers. Any thoughts if I need more boxing?
Currently I just have one brace on the outside.
Nothing on the inside though. The back side is 1/4" the front side is 3/16 plate. Yes I know its heavier than needed (160lbs), but it is a prototype...
You're well past good. If you were going to put 38" tires on it....you'd still be good.
 

luthj

Engineer In Residence
Okay, shocks on order. Given the current factory lead times, its 4-6 weeks. I could have probably gotten them faster from another source, but that would not have included any custom tuning. Given the weight difference, and ride position difference, its worth the wait I think. Not that I couldn't tune them myself with some trial and error, it would have taken considerable time and effort, and I value my time fairly highly. After becoming an expert in a field, one learns to appreciate how hard won knowledge can be.
 
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luthj

Engineer In Residence
I would like to have the shocks in hand and measured before I send for fab. But if I can get a few dimensions from fox, I could move ahead with fab, and leave the shock towers off just in case.

Once I get the steel, the actual welding should be pretty quick with the tabs.
 

b dkw1

Observer
Ryan should be able to get you any dim's you need.

Quick is relative, that's a lot of rod to throw down. A lot of tacking to lock it for welding. Your going to have to jump around a little to keep it from becoming a banana.
 

luthj

Engineer In Residence
I took advantage of the 4th sale at the local junkyard. I pulled a NAG1 from a 07 grand cherokee. It will need a different adapter housing. The trans mount and cross member look like they could be useful. I have not decided if I want to keep the sprinter cross member and just lower it or not.

At some point I will go through this trans, and see what internal differences there are with the sprinter. I know the sprinter has a few extra plates in a few clutches, and it has a heavier second planetary. Hopefully this unit has the right gearset, and the housing depth is correct.

IMG_20190704_113947866

IMG_20190704_120212640

image-20190704_124052

IMG_20190704_201300977

IMG_20190704_201307503

IMG_20190704_201315677

In other news I pulled the first 242D apart. It looks pretty good. I guess there was some metal crap stuck in the mainshaft bearing, which was making the noise. I cleaned it out, and it runs smooth now on the bench. I will replace that bearing and the seals, and keep as a spare.

I also think that the NV245 may have an input gear that fits the 242, but with the external 26 splines. There weren't any in the yard to check though. The 245 has the 2.72:1 low range, so I would bet it uses the same planetary as the 242. The real question is overall length, and input bearing width.
 
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