CaveVan Forum

VW T4 "Eurovans" => Diesel Swap Tech and FAQ => Topic started by: Strawman on June 01, 2017, 12:00:31 pm

Title: 15k miles on AHU swap into '93 Weekender
Post by: Strawman on June 01, 2017, 12:00:31 pm
I thought I'd give an update on my swap, since I just logged 15k miles since I completed it. I never started a build thread, but I've posted a couple of times in others' topics.

To summarize, I melded two 1993 Eurovans and one 1997 Passat TDI. I started with a San Diego Craigslist-sourced white poptop Weekender; it has a salvage title because it rear-ended a car and then was punched in the rear in a big SoCal pileup. It originally came with an automatic but only had 110k miles and was otherwise pretty clean. Not bad for $3500, although it was a 12-hour day to pick up the van using a friend's truck and a U-Haul trailer. I then bought a local 1993 EV that was terribly abused and had a blown headgasket for $500 -- but it had a manual transaxle. After removing all manual trans-related parts, as well as the parts to fix the crash damage on the Weekender, I sold off the remaining parts and came out about even. I then bought a San Francisco Craigslist-sourced '97 Passat TDI with 200k miles on it for $2200 to use as the donor. I drove it for several weeks to make sure everything worked, then I began the teardown. I grabbed the engine, harness, dash, etc. and sold off about $1000 in unneeded parts.

I used a Kerma Stage 1 chipset and blueprinted DLC1019 nozzles, but the engine is otherwise stock -- even the turbo. I replaced all engine seals/gaskets (including resealing the injection pump), hoses, installed a full timing belt kit, upgraded to a VR6 oil cooler/filter mount, and mounted the stock Passat intercooler behind the front bumper with holes cut to flow cool air (also welded up a "box" to direct air through it rather than around it). I sourced the correct oil pan/pickup, dipstick, fuel tank pickup, motor mount arm, and various other parts from Frans (info@dutchautoparts.com) in the Netherlands. I run an Auber Instruments digital EGT display in the dash (probe mounted correctly in a drilled/tapped hole in the exhaust manifold) with an alarm set at 1450 degrees Fahrenheit, as well as an Auber digital boost gauge and a GM 3-bar MAP boost sensor. The EGTs typically run at 650 to 700 degrees while cruising, and 1100-1200 going up hills or entering a freeway. But I can set off the alarm going up mountain passes if I'm too aggressive; it'll instantly cool back down by pulling my foot out of it a bit. Kerma says to install a Colt cam to bring down the EGTs if I desire, or possibly a bigger turbo and larger intercooler. I'll wait for the stock turbo to die then I'll take the plunge for a Kerma-sourced S7 turbo and related parts. I'll probably also do an EGR-delete at the same time, since Kerma will provide a free updated chip when you buy upgraded parts from him. I sourced a used PD150 intake manifold from Ebay UK in anticipation of those future upgrades. Paul (the main dude at Kerma) may seem a bit grumpy to some folks, but I found him and his staff to be damn knowledgeable and helpful. Can't say enough about Kerma...

I also used a South Bend Stage I clutch setup to handle the purported 150 hp and 300 ft/lbs torque, and the clutch pedal feels like a stock unit. I started out swapping the 0.756 fifth gear from the Passat transaxle into my 02B CHP trans, but it was still way too low -- I had to shift to second gear just to make it through an intersection, and it revved at ~3300 rpm at 70 mph. After about 3k miles, I ended up getting an EWB-geared trans from Frans shipped to my door for ~$1400, and it is now perfect. It revs about 3k rpm at ~78 mph on 215/55-16 tires on stock alloy EV wheels. I ended up selling my original CHP transaxle for $350 on Craigslist.

I mounted the chipped-ECU in the engine compartment where the old gasser ECU was mounted. This required me to extend a few wires. Because I am in CA, I used all stock Passat pieces to the extent possible in anticipation for a refereed smog inspection (no sniff for pre-1998 diesels; another reason to use an AHU!). This required me to weld-in mounts to use the stock intake airbox, which meant I had to mount a windshield washer bag/pump since the stock EV washer bottle would no longer fit. I grabbed the bag from the rear of a mid-90s Isuzu Trooper (was used for its rear window wash system) at a local Pick-n-Pull. I also used the Passat turn signal / cruise control stalk. I concocted/welded a mount for the throttle potentiometer, and welded the lower portion of the EV throttle pedal to the upper Passat portion -- it came out great. A local hydraulic hose guy built me a custom high-pressure line for the power steering system, essentially mating up the Passat pump end and the EV rack end. I also enlarged out the mounting holes for the EV A/C compressor in order to mount it to the AHU brackets, since the Passat compressor uses larger mounting bolts.

Challenges:

*  I had a heck of a time getting my cruise control to work consistently, and my VCDS didn't show any faults. I finally realized that my brake light switch was uber-sensitive -- like, hit a bump on the freeway and the cruise control would go off. I replaced the brake switch and it now works flawlessly.
*  I have a CEL fault for the coolant glow-plugs that I'm still chasing down. It doesn't seem to affect performance, but I'm getting tired of the light staring at me.
*  Because I had to get my vehicle through CA smog inspection (once only to register!), I cut/clocked/welded the stock cat/downtube to clear the firewall but also tried to make it look entirely stock. It turns out the guys at the local DMV just looked at the Passat emissions sticker (still on the plastic piece that I literally bolted onto the EV radiator support!) and he punched it into the computer as a diesel -- so my EV is now registered in their system as a diesel!
*  My van puts out virtually no heat, so I'll pull the dash in the coming months to fix the flapper plates and replace the heat exchanger while I'm in there. I'll also try to add some insulation on top of the firewall, since it is relatively noisy from the engine bay. I'm also constantly on the lookout for the stock under-hood insulation.

We just got back from a music festival in Napa and the van was LOADED with four adults and all of our camping stuff (the other couple had a big tent and a queen-size blow-up mattress), and four bikes on the rear hitch-mounted carrier. I cruised at 70-80mph with the A/C blasting, and I even passed cars on the two mountain passes between SLO and Napa. But I still got 29.5 mpg. I get almost 31 mpg around town, but seem to average 30 mpg in mixed driving. I use 2 oz. of Stanadyne Lubricity Formula at each fuel fill, at Kerma's recommendation.

I love my van, though it still needs some bodywork and paint to make it perfect. It is mostly our weekend getaway rig, but it has been my daily driver for the past five months because my other car ('96 BMW 318ti) has been getting a complete respray. You could say I've got a swap addiction, since I swapped an M3 engine into my 318ti and I've got a 1973 Porsche 914 that I swapped-in a Subaru WRX engine and transaxle (converted to 2WD). Past swaps include Subaru EJ22 engine into 1986 Westy Syncro (completed in 2001), Golf GTI engine into 1981 diesel Westy (in 1998), and Sidekick engine into 1987 Suzuki Samurai (in 1996) . It helps to have a two-post lift, a bunch of tools, some hard-earned knowledge, and -- most importantly -- an understanding wife!
Title: Re: 15k miles on AHU swap into '93 Weekender
Post by: JoshWa on June 01, 2017, 02:53:28 pm
Nice swap!  You've put more miles on yours than I have, and mine has been done for a year and a half.  AHU from a Jetta though.

I'm running a CPW with a .711 5th and running 70mph at 2900rpm.  1st-3rd is not great though.

Where did you locate your EGT?  I've got no idea what temps I'm hitting.  But you're right, the engine does run cool.  I did get my fans to come on though.

Also despite my efforts, I've not been able to calm some of the vibes through the steering wheel and stick.  Was there a difference in vibrations for you between how the rear mount is for the CPW vs the EWB?

I just bought on a whim a wrecked 96 Passat with a 1z to do another swap down the road.

Happy diesling.
Title: Re: 15k miles on AHU swap into '93 Weekender
Post by: goose on June 14, 2017, 10:48:31 pm
 Hi guys:
I'm also a proud owner of a TDI EV.  I haven't blogged about it but I sure appreciate all of the work everyone has put out there on the net for me to glean info from.
My conversion started as a 1995 Winnebago EVC that I picked up last summer (2016) in Ventura , Ca.  it was a MT with a blown engine, and the price was right. 
I then sourced a ahu from a 98 jetta from Santa Fe, New Mexico and ewb tranny from Frans.  other bits and pieces from all over.  I used a Vnt 15 turbo and Dsla 1019 injectors with a modified AFN ecu tune.  The conversion took me about 6 months to "complete" and we are pretty happy with the product.
It wouldn't have been possible without the help of a very skilled individual Andrew Clink who as a result of this endeavor is now a good friend. 
Performance wise its still a work in progress.  My mpg's are running around 22-27 combined city highway and EGT's are higher than what you guys are seeing with 700-900 around town and 900-1250 on the highway. I'm guessing the added weight  could be the culprit.  I'm changing the exhaust to a 2.5" with magnaflow diesel cat and no muffler this week so we'll see if the egts are affected.  I currently have the egt probe mounted in line with the #3 exhaust port.  when I upgrade to a vnt 17 ill place it directly inline with the turbine inlet. 
Its great to hear other peoples story lets keep it going.
Title: Re: 15k miles on AHU swap into '93 Weekender
Post by: Robinasu on August 06, 2017, 12:32:42 pm
Strawman, really cool work! I'd like to do this soon. Do you happen to have an excel sheet with parts, etc?

It would be really cool to see a very professional DIY on this topic with no gaps. Maybe one exists? If people pump the information my way I'm offering my documentation skills.