Building a diesel powered RHD TJ Wrangler (Picture Heavy)

[RustyAutoholicGuy]

So I am not at all familiar with what you can do tuning wise with a TDI since I am coming from LS and HPTuners and Holley, but are you not able to change the target idle speed to match closer to a 4.0?

These TDI will not idle below about 882rpm, actually the Bosch EDC16 will not allow you to put in a value lower than 882rpm. Roughly speaking there are two types of diesel engines, long stroke and short stroke diesels. While this isn't 100% accurate, it helps with how you have to think about it.

Long stroke diesels, like my Kubota V2403 or the Cummins 4BT have a much longer stroke, thus they are able to idle lower but they also have a lower maximum RPM, for the Kubota that was about 3100rpm.

The TDIs and Mercedes OM60X series diesel engines are considered short stroke. They have a higher idle RPM to keep them from stalling but also have a maximum RPM of around 4500rpm or higher RPM. I know for the ALH TDI, the previous generation to the BEW TDI, you can modify the valve springs and a few other things in the cylinder head and get the engine to rev over 6000rpm, though I've never seen a need for that.

Hopefully that helps!
Grant

 

[RustyAutoholicGuy]

Hey TJers,

Over the past month, I've tackled a few of the smaller less flashy items that I've been needing to get done on my TDI swap in my TJ Wrangler, installing a more permanent air intake system and sealing up the hole I cut in my firewall to pass through the wiring harness for my BEW TDI with a split grommet.

The air intake setup for my turbo has been long overdue. While the pod air filter I was using was functional, it was also sucking in hot engine bay air once everything got up to temperature.

I initially thought I could use two silicone joiners to directly connect my Volant Air Box to the inlet on my GTD1752 turbo however my engine is about 1 inch too far forward for that to work.I ended up getting an aluminum pipe that has a 180° bend in the pipe so I could make everything fit. Initially, I went with a 2¼ diameter aluminum pipe. Still, it was obvious that the BEW TDI engine didn't sound the same with that setup, so I ordered another set of silicone joiners for the air box and inlet for my turbo so everything could be 2½ instead. This allowed everything to breathe much better.

While waiting for the larger diameter parts for the air intake system to come in the mail, I installed the split grommet on my firewall. Not much to say here about the installation, just drilled 6 holes and mounted it with new fasteners to hold everything in place. I will say the first time I drove my TJ with the split grommet I noticed two things, first the amount of engine bay noise was reduced significantly, though that was expected. What I hadn't thought about was the amount of heat that spilt grommet prevented from coming into my cab.

I will say the combination of the air box and the split grommet has made the driving experience of my TDI-powered TJ Wrangler much more pleasant. I don't hear my GTD1752 turbo anymore at lower boost pressures, which makes highway cruising a much more pleasant experience. I don't have concrete data for this yet but I'm confident that my fuel economy has improved slightly with the Volant air box setup as well because I'm no longer sucking in hot air from right around the exhaust and turbo. I will conduct another fuel economy test in the near future to confirm that as well.

Overall all these two changes are getting me one step closer to being completely done with this swap, though I still have an extensive list of things left that I need to tackle.

Here is the video if you'd like to watch:

Let me know what you think!
Thanks
Grant