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John's 98 Build Thread

John, Can you comment on how the 3.73, AX-15 combo is? How is it on the trails? Would you say it's ideal for a daily driver? What's your MPG's with that setup? Thanks!
 
3.73's and an AX15 is nice. 3.73s, AX15 and a 31 spline NP242 is awesome. I do wish it was a little lower for wheeling. I've been contemplating solving that with a crawl box. We will see how budget looks in a couple months. Gas mileage... I drive 25 miles to work every day on the interstate at 70-80 mph, and average 16. In town I average 14. It used to be 20-23 mpg and 15-17 in town. I guess too many off-camber oil starvation situations or the poor maintenance of the last owner has stolen the last of my compression. There is something very very wrong with my 4.0, and I just don't care to fix it since it's getting pulled. I'd totally expect the average XJ on 31's/ax15 to be fine off road and average 15-17 in town and 19-23 on the highway.

Sent from my Nexus 6 using Tapatalk
 
Thanks guys! I was on the fence between 4.10s and 3.73s, And this pushed me to find some 4.10s for the 265/75R16 I'm running. 3.54s weren't deep enough for the five!

FYI: I get about 18MPG with the 4.6l stroker, 3.54s & AX15.
 
I've been trucking right along when my wife and I aren't working on house projects. I've been focusing on 2 fronts.

AC Compressor
After much measuring and remeasuring I picked up the 4660. It fits like a dream, BUT the lines are going to be tricky. It interferes with the frame mount when the outlet is clocked 90 degrees, and interferes with the regulator on my alternator when its not clocked. I will be ordering some low profile 90 degree fittings to see just how tight it is.

IMG_20160818_200543.jpg


CCD Bus translation

Low and behold, Alexia published his project to use a haltech ECU with the CCD gauges, in his Jeep. Unfortunately his project does not implement any of the features that allow bus components to share the bus, he just bit-bangs the bus without calculating a CRC or checking if it is okay to transmit so when a collision occurs the cluster reboots. I will be continuing work on getting the CDP68HC68S1 working so I have idle detection and collision detection to allow my other CCD bus accessories such as my overhead console and airbag controller to remain functional. So far I started by building a shield for a teensy with the needed hardware to make CCD work. I datalogged a good hour and a half of driving, and I have documented about half of the addresses on that bus.

Alexia's work on github: here
My hacked together datalogger: here

IMG_20160821_144320.jpg


Here's a CCD bus dump from yesterday. (10MB)


Addresses I've gathered so far
  • 12 (0x0c) - volts, oil pressure, coolan temp
  • 35 (0x23) - No clue, data is always 0,15, CRC
  • 36 (0x24) - mph/kph
  • 37 (0x25)- fuel level
  • 58 (0x58) - No clue, data is always 34, 16, CRC
  • 68 (0x44) - fuel pulse width??
  • 80 (0x50) - Airbag Good
  • 100 (0x64) - No clue, data is always 226,255,1, CRC
  • 109 (0x6D) - VIN (position, ascii, CRC)
  • 132 (0x84) - distance increased, (.0416 miles per bit)
  • 164 (0xA4) - Feature Status
  • 172 (0xAC) - chime - always 5, 130
  • 204 (0xCC) - accumulated mileage??
  • 218 (0xDA) - trip reset??
  • 228 (0xE4)- tach/map
  • 236 (0xEC)- Check Gauges light
  • 254 (0xFE) - appears tied to RPMs??
 
John how is this build coming along? We havn't heard much from you. diesel swap would be an amazing kit.

Hey man, my kitchen remodel has eaten all of my free time recently. The project is NOT dead, I just bought a timing belt for the engine, and collected most of the components to complete the BSM delete. All I need to do mechanically to the engine after that is clean the intake (they coke up) and install a cam. I did drop the oil pan on the TDI last weekend to check the status of the BSM and found part of the idler in the oil pan. Not shocking.

I also picked up a B5.5 Passat TDI to drive around while I have the engine out of the XJ. Its been averaging 34-36MPG! Since I put 80 miles on it a day 6 days a week its nice to not be getting 12-14mpg.
 
Its been quite a while since I last updated my build, and my, how things have progressed.

I have no use for the balance shaft module and the massive engineering abortion that it is, so I went with an ALH/BEW oil pump, pickup, chain, tensioner, and oil pan. I used a BRM pump drive sprocket to increase idle oil pressure. This by itself makes the BHW more reliable because the balance shaft module has a tendency of spontaneously failing, leaving the engine and turbo without oil.

brm_chain_400.jpg


oil-pan.jpg


I made a first pass at implementing a CCD translator. This will largely be reworked before the project is over, because I have learned a lot about board design and the requirements have changed as the build has progressed.

schematic_3-11-2017.PNG


600-pcb.jpg


I scored a diesel gauge cluster on ebay.co.uk, and a left hand drive dash bezel with the diesel message center on megaparts.eu

cluster.jpg


I am replacing as many plastic components as possible on this build for longevity reasons. EAA engineering had a cast aluminum thermostat housing that I scored. I do not believe they still make these, but INA occasionally does short production runs. There’s also a Chinese manufacturer making these, so if you are following my lead, all hope is not lost.
I also found a metal dipstick tube extension to replace the plastic one that’s always broken on ECS.

600-thermostat_housing.jpg


I drew up an adapter plate for the turbo of choice, and built a prototype.

600-paper_template.jpg


600-bhw_gtc1549gz.PNG


I have wanted a 6 speed for this swap for the wider gear ranges, I got a NOS NSG370 with all the factory improvements already done, so in that goes.

transmission_and_engine.jpg
 
The starter contacts the bellhousing of the NEW NSG370 that I found, so out came the sanding drum.

clear_starter_before.jpg


clear_starter_after.jpg


Once that was out of the way, I replaced the rear main seal and bolted up the adapter, along with a new centerforce extra heavy flywheel and a LuK clutch and pressure plate

adapter-2.jpg


clutch.jpg


transmission_and_engine.jpg


When I bolted the transmission to the adapter, I figured out that the coolant flange outlets both contact the bellhousing, so I cut both up, drilled and tapped the housings and used Loctite 577 to permanently seal everything. I am super happy with the final product.

raw_flange.jpg


threaded_flange.jpg

complete_flange.jpg


My wife got me a crawl box for Christmas, so expect some epic crawl ratios!

crawl_box-1.jpg


crawl_box-2.jpg
 
The Jeep moved into the garage last fall in anticipation of having time to pull the engine this winter. That paid off, in February weekend I pulled the engine!

1_in_garage.jpg


2_font_clip_off.jpg


3_hoist_in_place.jpg


4_engine_coming_out.jpg


5_empty_bay.jpg


The engine slipped right into the engine bay, unfortunately the compressor that I obsessed over fitting in the stock position contacts the frame.

6_tdi_going_in.jpg


7_tdi_in.jpg


8_engine_is_small.jpg


9_it_fits_yay.jpg


The compressor bracket from EBay by some miracle bolted right up to the existing holes in the block on the other side and clears everything, so that placement was used as a template for a future permanent mounting location.

1_ac_mount.jpg
 
I also moved the powersteering pump up. I fabbed up a bracket out of ¼” steel and a couple 17mm spacers to replicate the proper offset for the belt.

2_ps_bracket_mockup.jpg


3_actual_bracket.jpg


4_bracket_mounted.jpg


I liked the compressor location as mocked earlier, but I can't do anything simple apparently, and figured I could get the compressor a little closer to the block. I was already struggling to get the belt routed with the last layout, and the idler options and locations sucked. I found a nice small 55mm idler that's used on some diesel that was in the Grand Cherokee.
Dayco 89535, Four Seasons 45908 pulley bushing and a MOPAR 6503230 spacer. The bearing is of the correct perspective that it will not be outside of its safe operating speed when used with the TDI crank pulley.

I have been using some 1/8" plywood for mocking up my brackets, this is no different. Its super easy to work with and can be used to actually see how things mount. I used my spare block to test fit everything.

1_wood_mockup.jpg


When everything was mounted on the spare block, I could more easily mock up a brace for the rear of the compressor:

2_spare_block.jpg


I lopped the power steering mount off the accessory mount while I had everything off the block for testing:

3_final_mockup.jpg


Here's the completed mount shy one idler:

4_bracket.jpg


I am super happy with how this turned out! I scanned the final bracket if anyone wanted to replicate it.

5_final_mounting.jpg


The final belt size is K60740. Ill be getting a Continental Elite before I start driving this thing, thats just a $10 belt from amazon. I love Goodyear Gatorbacks, but they've been renamed.

The clocking of the transmission was off, I chose the middle of the three holes for my first stab, apparently, I should have used the most clockwise hole. Engine out, engine back in!

6_engine_out.jpg


Much better, however the TJ shift tower puts the shift cane right into the dash in any of the upper gears. I'll be ordering a B&M short shifter, hopefully that moves everything a little further forward.

7_shifter_location.jpg
 
Here's the opening in the floor with the AX15 specific adapter removed:

8_raw_opening.jpg


B&M 45195 is a perfect fit! I knew JK parts were useful for something... ;)

b_and_m_installed_1.jpg


Just a side by side:

b_and_m_side_by_side.jpg


Its a pretty big difference.

Just for grins I installed the console to see how everything fits, and I am super excited!

b_and_m_installed_2.jpg


Next step: Cut a hole in the transfer case tunnel since the driveline is 9" longer than it ever was with a 4.0 since I have the crawl box installed. (don't mind the gap, its just a test fit)

crawl_box.jpg


I left off with the transfer case clocked at the stock XJ position, BUT because the transmission adapter pushes the transfer case back so far the front driveshaft interferes with the crossmember. I decided to cut the transmission tunnel up to clock the transfer case up, and out of the way.

Here’s what I started with:

1_angle_pre.jpg


2_floorplan-pre-cut.jpg


The first step was to cut a big enough hole that everything fits, and test fit with the seat frame.

3_floorplan-seat-out-testfit.jpg


Then I started filling the hole back in, one jigsaw puzzle piece at a time.

4_floorplan-fill-with-metal-1.jpg


The bottom hump needed to be notched to fit the seat frame.

5_floorplan-fill-with-metal-2.jpg
 
I ended up with this. I used seam sealer to smooth the edges underneath, along with por15 chassis coat and finally underbody rubberizing spray.

6_floorplan-fill-with-metal-done.jpg


7_floorplan-fill-with-metal-done-under.jpg


Everything fits like a glove!

8_floorplan-carpet-back-in.jpg


Here’s my final clocking:

9_floorplan-xc-clocked.jpg
 
I’ve been super busy on this Jeep! My list of things to do has got much shorter.

The air to water intercooler is pretty neat, as it really shortens the whole thing. I got a kit from frozen boost, with the bosch pump. The bosch pump fits nicely on the passenger side frame rail. I still need to wire it up, and I’m planning on the pump running in the RUN position.

awic_with_fill_neck.jpg


awic_cooler.jpg


awic_pump.jpg


I finished up the fuel delivery system. I settled on a Stanadyne FM100 with a hand primer. I added a 30psi gauge to the filter outlet. I also used 30R9 for the return and reused the supply side. The 30 gallon tank was plumbed so if the Cummins pump fails, the auxiliary straw from the fuel module can just plug and play without dropping the tank.

fuel_tank.jpg


stanadyne.jpg


I plumbed up the power steering system, and added a cooler to the front. I used Russell Performance PowerFlex for the high pressure hose and ATF rated hose for the rest. I used a BMW reservoir and a hasty mount with a hose clamp above the pump. I am really liking the reusable threaded AN fittings you can buy these days.

coolers.jpg


I also got the Webasto mounted. I’m still waiting for some fittings for it for the fuel supplu, but its not moving.

webasto.jpg


I bolted a volvo cooling fan to a Jeep fan shroud for cooling. Should be overkill. I’m also using a temperature switch from a golf, threaded into the factory jeep sensor port. More to come on this when I finalize the wiring.

fan_starting_point.jpg


cooling_fan.jpg


I finished up the boost track. I used 2 inch aluminum tube and silicone joiners to plumb the whole thing. I also spent a lot of time getting the York sc609 bolted up. I’m looking forward to having this guy for belt driven air.

boost_track.jpg

york_mounted.jpg


Next steps:
  • Vacuum lines, reservoir and N75 bracket
  • plumb heater, and build overflow bottle
  • Finish AC (replace condenser, evap, lines, heater core while I’m at it)
  • Finish wiring. Have a plan, just need to do it.
  • Make a non-prototype CAN-CCD gateway. This is sitting on my bench stress testing in breadboard form with actual code running the gauges!
  • Get drivelines built
  • Transmission tunnel cover
  • Transfer case linkage.

I’m pretty excited that the front might stay bolted on this time!

front_reattached.jpg
 
It is time for my wiring writeup. I’ve put a lot into the wiring on this Jeep. I’m only going to document the non-obvious parts. For the obvious parts, I used this diagram:

edc16u31_wiring_diagram.png


AC Control

The AC is the craziest, so I’ll start there. The AC Circuit is broken into three parts:
  1. AC Request Relay
  2. AC Clutch Control Relay
  3. Fan Request Relay

The Jeep controls ground a wire when AC is selected. This for our purposes is called AC_Request. AC_Request on the VW side is 12v+, so we need to flip that around. Next, we have the “Bidirectional Climate Control” circuit (94/50), which in VW goes to either a climatronic, Relay 378 on the B5’s or a Fan Control Module in the A4 types. This pin is pulled to an internal 1.8v supply when AC is allowed by the ECU. This is worthlessly low to us, so I used a couple off the shelf transistors, resistors, and a diode to convert to 12v to drive yet another relay to control the Compressor Clutch. We also need our cycling switches, so we hook those up to ground and to the other side of the clutch control relay.

ACDiagram.PNG


To waterproof the transistors, I put them inside of a piece of heavy duty waterproof heatshrink.

ac_enable_pcb.jpg


ac_enable_module_sealed.jpg


The next piece of magic, I used a 2 speed Volvo fan and relay. It switches the fan on based on either the low or high wire being connected to ground. In order to do this but only when the jeep is on, we need yet another relay.

ACFanRequest.PNG


Fan Control

The two speed Volvo fan and relay are a good junkyard snag – the fans are very high flow and slim, and the relay is well matched to the draw of the massive fan. I mounted the fan relay between the battery and fender, so the wire can remain short. To switch the relay I snagged a thermal switch out of an A4 platform car, 1J0 959 481 A. It threads right into the jeep radiator. I de-pinned a connector (1J0 973 203) I got at the junkyard and connected it up.

thermal_switch.jpg


thermal_switch_pinout.png


1 - Low
2 - Ground
3 - High

Coolant Glowplugs

The coolant glowplugs in the A4 platform are switched by two relays. One is a 70A Bosch Mini, and the other is a standard 40A. The combined circuits are 50A, so this one is super straight forward. Throughout this, I reused my Jeep relay box, which for space reasons is primarily made up of micro relays with a max rating of 20A. Each coolant glowplug is rated at 17A, so we can easily use three relays instead of 2 and keep everything stock in my relay box!

CoolantGlowplugs.PNG


relay_box_final.jpg
 
I threw a belt! As predicted by some, the belt walked into the timing cover and shredded all it was worth. Fortunately, I was sitting in the drivers seat and turned it off before any damage could occur. The fix is to use pullies with flanges. Easier said than done! I read somewhere that the recommended maximum bend radius for a pk6 belt is 90mm, so there just aren’t a lot of pullies to pick from if you need a smaller circle. I already went through this selection process once. I settled on an industrial pully from McMaster-Carr 6235K68 for the smooth side of the belt, and a Gates 38082 for the grooved side. The belt length remained constant but is significantly tighter. The McMaster-Carr pully is for industrial belt and has a 6203RS bearing like everything else so it should hold up just fine. I bought a couple so I can keep one in my glove box.

thrown_belt.jpg


There have been requests for my turbo adapter design – here it is. Let me be clear, I had Matt Whitbread manufacture mine, I do not know what, if any, changes he made.

I was concerned that the exhaust was a tad close to the firewall, so I wrapped it. All in, wrapping a downpipe is pretty straight forward. I used a DEI basalt based wrap, finished it with stainless zip strips, and sealed it with a silicone exhaust temp. I like how it looks!

bare_pipe.jpg


wrapped_pipe.jpg


silicone_sealed_pipe.jpg
 
One other thing I’ve spent a lot of time on is the transfer case shifter. I really like the looks of the atlas twin stick cable shifter, so I got one. They are quite pricy, and unbeknownst to me use a non-standard cable length, so there was a lot of fab to make it work.

twin_stick.jpg


The simplest modification was the EcoBox bracket. I bought Jon Barlow’s bracket for this expecting everything to bolt up. I ended up shortening and flipping the bracket to work with the shorter throw cable of the atlas shifter.

blackbox_shifter.jpg


The more complex one – the NP242 has a very long throw. The shortest of shift levers was still too long of a throw for my cable, so I had to fabricate up a bellcrank to lengthen everything. To make matters worse, the bracket I bought for this was from Dirtbound Offroad, and it was incompatible with the strengthened webbing of the EcoBox. I ended up needing to cut it in half to get its mounting ears into place.

np242_shifter.jpg


I found a new turbo on ebay, the original was definitely failed. I could not find signs of wear, but the bearings don’t feel too hot. Once the new turbo was bolted up, I got a tune from Malone Tuning, and drove to the gas station to fill up. 30 gallons of diesel ain’t cheap!

first_fuelup.jpg
 
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