Project TDI Cabreetle

[alphaseinor]

Project TDI Cabreetle!

This is my former VR6 Cabrio: VR6 is going into a Miata for maximum fun.
BHW block with ALH head and IP engine swap into a MK3
Transporter Pistons
MK4 wiring harness swap
MK4 Beetle Dash, Air box, and airbag system
Manual convertible top conversion
96/97 Passat 5 speed conversion with .658 installed
VR6 axles
Mk3 TDI engine mounts
Mk4 shifter (2000 Beetle conversion)
Dieselgeek Sigma 5 short shifter, First gear getter and new bushings
VR6 subframe
5 Lug conversion on all 4 wheels
16" VR6 wheels (eventually)
Glass headlights


Stuff already done on the dash:
verify beetle dash will work (actually TT dash fit nice as well, but I'm doing this with spare parts)
Remove old dash cover
Remove dash beam
Remove pedal box
Remove Distribution Box
Clean up some of the wiring under the dash
Remove engine harness from under hood
Remove MK3 fuse/relay panel
test fit/relieve dash support
test fit/dash for clearance on doors
Take photos of dash in place to post here

Stuff needing to be done on the dash:
Finish culling the wiring
Install MK4 body harness to front of vehicle, retain MK3 body module and rear/door harnesses
Install MK4 airbag controller
Install subwoofer wiring
CAD dash support brackets
Install dash support brackets, and dash support permanently
Install dash backing



Pulling the dash was a pain. This shows the new air box installed. Literally just installed with no issues at all. there are no upper mounts to the air box, so I'll see if they are 100% needed... might need a bracket fabricated to make it work right over the long haul. Yes the air distribution box needs to be installed to make the dash fit, the blower motor won't clear the new dash support (below)



Inserted dash support, one hole to drill and two brackets to mount it to the MK3 platform, two notches needed in the tubular beam to clear the mk3 bodywork (about 1/4" offset on the back of the tube needed, pie cut from the two vertical quadrants. Takes 1 minute to modify. Needed an additional 1/2" spacer for the beam adjuster connecting under the rain tray.
You'll need the following part numbers:
Qty 3, N 905 814 01 plug (plugs the bolt holes for the other dash beam)



Inner dash installed (temporarily to check for fitting)



Outer dash skins installed (temporarily to check for fitting)



a view from the outside of the car

 

[alphaseinor]

Working on the wiring, and how the mk4 pedals will fit (not sure if I want to use them yet

So the pedals are an interesting challenge.
The clutch pedal will be about 1" higher than the brake pedal if we use the Mk4 clutch pedal, one option is to use the MK3 clutch slave, but the clutch pedal switches will need to be offset a bit to make it work, not sure what the over center spring will do if used any lower... so MK4 pedals might be out.
If I need to do the Mk3 pedals, I can use the existing cable driven throttle pedal with a '98 beetle TDI throttle position sensor. I just so happen to have one, but it'll need to be fabricated to make it work correctly.



Modified to use the Mk4 clutch pedal box.


it fits!


Too bad the clutch pedal height is totally uncomfortable.

 

[alphaseinor]

Reserved for body wiring stuff

 

[alphaseinor]

Engine Stuff / Transmission stuff.


BHW block with modified T4 2.5L pistons
Currently stock size rods, but will be upgraded before I stick it in
yes, it has a pump, not a balance shaft.
It's got a little surface rust, engine has been sitting for about 6-7 years, finally getting to it.
As far as I can tell, so far the Mk3 engine mounts will bolt right up to the back side of the block

Going to need to find the PD150 intake that routes the wrong way, also thinking about using a turbo setup with the cold side on the wrong side as well...
Got the larger version of the TT 225 HP right side intercooler, it just barely fits. going to be fun plumbing it.

As for the transmission, thanks to having a VR6 donor, the axles bolt right up to the VR6 flanges from the 02A, which slide nicely into the Passat transmission.

 

[alphaseinor]

reserved for engine harness/ecu wiring

 

[alphaseinor]

reserved for CAD files

 

[alphaseinor]

Updated a couple of posts above.
Mostly I get to figure out the mk4 clutch pedal weirdness or use the original pedal box and adapt the 98 beetle throttle position sensor to work with the gas pedal on the mk3.

I'll see if I can come up with a reliable solution tonight or tomorrow

Fun times. gotta love franken-cars.

 

[Steve Addy]

Can't you use a Mk3 tdi pedal cluster? That would give you a pedal cluster with stock fitment and none of the pita. Isn't the only difference that wiring is reversed on the Mk3 vs Mk4?

Steve

 

[alphaseinor]

Heh, true... I'll see if I can get one out of the junkyard this weekend