Go diesel...
Since the engine swap is still a ways away I'd suggest going diesel! My 91 YJ will get this eventually...I dig it and they are some smart folks. Sorry if the clip/past of the email they sent me doesn't show the pics...try their web page for details.
You really need to determine which rear axle you have in your YJ. If its the 8 1/4 then you should be fines even w/32s. If you got stuck with the dana35...plan on swapping that. They like to break sitting alone in the parking lot at night!
HPA Jeep TDI Project August 16, 2010
Thank you for subscribing to our Jeep newsletter... Though we are old veterans when it comes to motor swaps and crazy vehicle conversions, the Jeep scene is somewhat of a new one for us and we appreciate your support.
While the step by step build process will be covered by JP magazine, we wanted to offer our loyal readers some insight into the direction this project has taken behind the scenes.
Initial study and conversion:
We started with a 1991 Jeep Wrangler YJ with the 2.5L 4cylinder and AX-5 gearbox as there seems to be no economical rebuild path for the aging power train on this very common package. The (PD) TDI engine we selected weighs in 55lbs lighter than the original 2.5L AMG motor we yanked out, and produces 45 lb-ft more torque that our Jeep would have done in its prime.
With the engine removed, the OEM frame mounts have been detached and our new mounting solution is bolted in. You can choose to either weld or bolt on our mounts, but our test mule will have these bolted on so we can stress test them long term.
We retained all original Jeep geometry from the flywheel back through a crank shaft adapter and bell housing adapter assembly. The OEM Jeep flywheel is modified to match the crank shaft adapter bolt circles allowing you to uses any off the shelf Jeep clutch kit. We have had many satisfied years of working with SPEC for all our high performance Volkswagen/Audi builds and as such have chosen their Stage 3 clutch kit for our Jeep project.
The engine has now been in and out of the Jeep a number of times as we documented and patterned the widgets that have gone into this initial build. It is very exciting to see the cleanly installed assembly as it looks like it could have come that way from the factory.
Our TDI is rated for 100hp and 180 lb-ft of torque stock in its stock form but has even more potential with a few simple performance mods. Because our conversion retains the original engine ECU, a power prom flash can easily be added to bump this to 165hp and 280 lb-ft of torque respectively.
Adding to this package, we have designed our downpipe to mate up with an off the shelf Magnaflow 2.5" exhaust system for the Wrangler. As it happens, 2.5" is the ideal diameter for maximizing the power of the TDI.
We are also exploring a custom cam for our PD motor that will smooth out its idle and adds a proven 12hp gain and 22 lb-ft of torque as a stand alone upgrade (outside any power flash).
Our team is only weeks away from unveiling the finished project, complete with some new goodies for the body and chassis, and we will have pricing available after the Labor Day long weekend.
We will be offering three groupings:
Grouping 1 is a bare bones package targeting the Do-It-Yourselfer. It will include everything required to take a late model TDI motor and physically integrate it with the 4cyl YJ driveline. Our team will supply a list of TDI engine codes that are best suited for this conversion.
As pictured:
- engine mounts
- bell-housing adaptor
- crankshaft adaptor
- Machined flywheel (exchange)
- Downpipe
Grouping 2 will include everything in Grouping 1 and will expand it with our custom air intake solution and an air to water cooling package, along with the coolant line flanges we have designed to retain the OEM Volkswagen cooling system.
Grouping 3 This package will be a little ways off but will include an entire engine assembly with the majority of the electronics prepared for installation; including radiator fan assemblies, etc.
For all three groupings, we will offer an "Immobilizer Defeat" service to those wishing to utilize the original VW wiring harness and ECU as we have done in our project. This will open the door to a variety of TDI power prom upgrades and retains access to factory VW OBD diagnostics.
Once the demo truck has been shot by JP magazine, we will bring in an AX-15 gearbox and start at the adaptor system for it, along with pulling in a 6 cylinder Jeep to verify that our current mount solution will cross over with no issues.
As always, we welcome your feedback... please email us your questions or comments.
Sincerely,
The Team at HPA Motorsports
sales@hpamotorsport.com
604.598.8520
