Thursday, March 1, 2012

85 Vanagon TDI stage III conversion

Yes yes, I know another engine build and another conversion getting underway.  This one should be straight forward enough to get it out the door within a few weeks.  1985 Vanagon Westy w/1.9 WBX and 4-spd trans getting a stage III TDI 1Z engine build along with a rebuilt/re-geared 4-spd trans with LSD, oiling plates, and 1.08 3rd and .70 4th.

Old 1.9l WBX engine/trans:

1.9l TDI 1Z Engine build:

 1Z block on stand crank laid, main bearing clearances checked and new bolts torqued to 48 ft/lbs + 90*.
 0.50mm over ASV pistons queued up for installation onto rods.
 Rods at the ready.
 With copious assembly lube pistons mated to rods.
 Pistons installed in eng and rod radial clearances checked.  Rods 2 and 3 in spec.
 Rods 1 and 4 in spec.
 Pistons installed and height projection being measured.
 ARP head studs installed and alignment studs on the diagonal corners to keep the head gasket perfectly aligned.
 Oh the beauty of new pistons in a rebuilt engine...

 Rebuilt cylinder head poised for sealing surface de-greasing.
 Cleaned up and ready for mating to short block.

Head mated, centering studs removed and head studs torqued to spec. Long block complete.

 Intermediate shaft pulley torqued and marked.  Torque spec on these is 33ft/lbs but through life's cruel lessons we have learned that's not enough and always torque them to 44ft/lbs AND use red loctite.  You do not want this bolt backing out on you!

A new elegant solution for the turbo oil supply line: Instead of the stock OE rigid steel pipe KermaTDI came up with this simple and sweet flexible stainless high press hose with the correct fittings on each end for the AHU/1Z with oil feed coming off the oil filter flange and not the cyl head (early 1Z).

The stock oil supply pipe is notorious for developing cracks resulting in deal breaking end of trip results with high pressure oil leaking EVERYWHERE.  The veritable Achilles heal of the AHU/1Z engine.

 Progression of an EGT probe install by the Freehand Machinist Artisan:

1) Ideal probe site is identified and then checked with turbo installed on eng to verify clearances.
Test incisions made to assess suitability
 2) Site is machined to provide a flat surface without side interference for 1/8" NPT probe install.
 3) Bit by bit the two planes are taken down with constant inspection inside to ensure suitable material thickness.
 4) Continued material removal until
 it's just

5) Mirror image cut with plenty of material for tapping and just enough room on the side.

 Clutched up! This is our STD heavy duty hybrid G60/WBX clutch set up we use now on our Vanagon TDI conversions: Lightened G60 flywheel (228mm), WBX disc (228mm), G60 pressure plate.  This set up can hold over 320ft/lbs torque and we've yet to find their slipping point even on our biggest builds (stage VI).  And on top of all that with this flywheel you can still remove the oil pan without removing the trans which isn't possible with the stock AHU/1Z flywheel.

Another view of our hybrid clutch set up as well as the new flexible SS turbo oil supply line.
 Rebuilt WBX tranny from GTA with 1.08 3rd gear, 0.70 4th, limited slip diff (LSD), SA oiling plates, reinforced case, etc.  Premium built 2wd trans.
 D side view of trans.

Build tag from tranny shop.

Intercooler time:

 View from below, turbo and L carrier bar.

 Intercooler system plumbing.
Electrical junction box--where the magic happens.

Installed TDI engine with coolant system complete, fuel system complete, power steering system complete, intercooler system complete, air intake system complete and wiring nearly complete.

Cluster mods

 Customized Vanagon cluster modified with check eng and glow plug light, tach to read TDI tach output signal, and two digital Auber gauges (L about headlight switch), to read EGT and boost or oil temp etc.  Slick, sleeper and stock.


***All pics and conversion work done by TDIpowered.


  1. hello Justin, what s the code for the 84 transmission - what's LSD in terms of the transmission? what tire size is on this 84 vanagon with the re-geared tranny and lastly where did you purchase the gears from? Thanks for your reply? Bruno

  2. Not sure of the tranny code. LSD is limited slip differential. Trans was rebuild at German Transaxle of America in Bend, OR.