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How To: Build your own 4.0L turbo Cummins (Beware...170+ pics)

I am, basically, pulling out one degree of timing per pound of boost. It is working well. IMO, the type of controller is not important, per se, as long as it gets the job done. Most believe that whatever piece of hardware they are using is the best. I believe that what ever floats your boat is the best for you.

I am partial to AEM electronics and run the F/IC 8 as, IMO, the extras it offered over the F/IC 6 were worth the extra expense. Opinions vary. One advantage of keeping with one hardware supplier is compatibility of the products. Thusly, I was able to just plug the UEGO Wideband O2 sensor's 0-5VDc output into the F/IC and read the AFR via the F/IC as well as on the A-Pillar gauge. Made tuning easier by far.

If one mixes the manufacturer, on then must "match" the sensor output to the device input via a correction table. IMO, it just adds a level of complexity that does not significantly add to the end result.

If I had my way, I would reprogram the PCM and do away with the piggyback altogether.

I am working on that idea as we speak. OK, as we write...

Keep in mind that the timing corrections must be all zeros in the cells that reflect the engine operating under NA conditions. Also, keep in mind that pulling back the spark excessively, will cause the engine to over heat.
 
SolarBell said:
I will have one soon for an AEM FIC, but not yet. However they are somewhat device dependent. Are you running an AEM? SplitSecond? MegaSquirt?
Click to expand...


Solar-- any timing info you can share will be priceless. I am running a MS3Pro from Megasquirt.


O-Gauge Steamer said:
I am, basically, pulling out one degree of timing per pound of boost. It is working well..

Keep in mind that the timing corrections must be all zeros in the cells that reflect the engine operating under NA conditions. Also, keep in mind that pulling back the spark excessively, will cause the engine to over heat.
Click to expand...

O-gauge- understood, thanks. I still will like to get a baseline/OEM timing map before I go tinkering with the boost timing. I am pretty sure it is all too retarted right now. No overheating issues, just low midrange (2000rpm) power in vacuum and piss-poor MPG (less than 10)
 
If you're looking for a simple way to manually control your AW4, here is a fix I came up with. It works great and was pretty easy to install. I know it says to not use torque converter lockup at full throttle, but on a dyno and not shifting between gears it shouldn't be a problem. You just don't want it to shift between gears in lockup at full throttle especially while in boost. I've had this setup for about 2 years and it's been great. You can turn it on when you want or shut it off and run stock configuration. It will hold a gear as long as you want.

Here's a link to my flickr page for photos of the schematic and the configuration of the switches. Enjoy:)

https://www.flickr.com/photos/77467221@N02/13603425533/
https://www.flickr.com/photos/77467221@N02/13603792434/in/photostream/
 
My current ignition table

IgnitionTable_zpsefede765.jpg
[/URL][/IMG]
 
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Well it's been a while and I don't have much in the way for updates. My wife has been struggling with some health issues, so the XJ has been spending most of it's time in the garage collecting dust.

I have a ton of work ahead of me before it will see any trail time, but right now I can't even afford to replace my severely cracked windshield. Good news? I have a bunch of fabrication work planned for this spring involving several new products that we'll be offering.

Thanks for the kind comments everyone! Your support has been awesome.

Patience is a virtue. :greensmok
 
Sorry to hear about your wife. These are struggles we all get to swim through at some parts of our lives.

We will be patiently waiting for upgrades down the road...
 
It was a great day to brush off the cobwebs and fill the tank. I then hit up the hills behind our neighborhood for some flex testing.

I can't wait to knock out some rear shock towers for this thing (hint drop).

Crap phone pixtures...















After I can recover from having to shell out an additional $1200 to the IRS this year on top of all the other crap that's been going on, I'll hopefully begin to tackle my to do list...

- Replace the windshield.
- Get the rear ARB installed and sell the detriot
- Emissions
- Replace the worn and leaking steering box
- Patch several rusted out sections
- Finally finish the front and rear stiffeners
- Rear shock towers/through floor shocks
- Finalize and test the winch tray/sway bar
- Fab a rear bumper
- Dyno
- wheel
- camp
- repeat

:cheers:
 
Built AW4 by fringe development. The factory trans did great for about 2 years, until it started slipping. I would have installed Fringe's upgraded valve body at the same time if it were available when I first boosted it.

It also has the transgo shift kit with the 1st gear hold option. I honestly didn't think I'd love the 1st gear hold as much as I do!
 
Tons of fab work has been getting knocked out recently! The goal being to get the rear suspension finished up so I'll be able to start the cage this winter.

On the list:

- 2" rear stretch
- rear stiffeners
- sheet metal shock towers
- prothane bump stops
- traction bar
- slider extensions/trusses
- front track bar brace













 
Looks good, just need to enlarge the fender opening. What'd you do for your rear stretch? Just redrill perches for the center bolt, or new perches like ruffstuff has?
 
Make sure you sell the traction bar you design for the rest of us on your website.
 
NCCherokee said:
Looks good, just need to enlarge the fender opening. What'd you do for your rear stretch? Just redrill perches for the center bolt, or new perches like ruffstuff has?
Click to expand...

That's what I'm working on right now, as well as getting the tubs cut and back into place. Then it's just a matter of patching the middle, some minor body work and seal the seams.

As for the stretch, I just drilled new holes in the spring plate. I'm running a home brew U-bolt eliminator setup with a longer spring pad.

The edge of the fender has been moved back 3.5" overall





 
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