Ultra4 4600 VW Touareg V10 TDI Build

[Pharr]

Hi! I'm Chris with Pharr Motorsports out of Austin, TX and this is our 2008 VW Touareg build thread. We are building this hotrod to compete in Ultra4. Yes, that's right we're a little nuts. First off.. a few common questions I get regarding this thing:

Q: "lololol a Touareg?? Really? Why?"
A: Yes. Remove the brand (or pretend it's a 4th gen Grand Cherokee if you love Jeeps ), look at the specs:

1. Big reliable power - yes, this can break things, but how's that sand hill treating you?
2. IFS/IRS - yes, tight turns suck. yes it's more complicated and not proven, and weight transfer sucks, and.. egh that's enough for now. However, part of this race is desert right?
3. NOBODY can say, as a matter of fact, that this will be slower, it's never been done. I'm doing this to find out, because I think it's faster.

Q: "I'm sorry, how wide? ....You're insane"
A: Probably, but consider this: It's no wider than the current two time consecutive King's car. "But you're on 35's" -cool, is the problem width or ground clearance? Because I have both in spades.

Q: hell i dunno, ask away..

A little background: In 2018 I purchase a 2008 VW Touareg with the V10 TDI sight unseen from a dealer in SC. It was the wife's daily and I'm still working on repaying her. For those that don't know, the VW released the Touareg in 2004 and it had the option of a v10 TDI producing 350hp and 550lb/ft of torque. Due to emissions stuff (lol vw), none were produced with the v10 in 2005. by 2006 they had made the changes to put it back into production. For the 2008 model year they had a facelift making them slightly pudrier. This was also the last year for the V10. It's a rare bird, indeed. This is my second V10 Touareg after the first was totaled.. a story for a different day. I scoured the internet for two months to find one that would hold it until I could fly out to get it. Rumer has it that there's only like ~82 of the '08 with the V10 option, and if you have one, you know what you have. So hopped in the plane, flew to the dealer, then drove it back to Texas.. 17 hours.

This is the first picture that I took of it:

Then I got the bug.

 

[Pharr]

A little background on me: motorsports has always been a part of my. My father owned a performance shop before I was born and would set me on fenders of cars he was working on as a kiddo. I entered my first race at 9 and won my first championship at 11. I mostly drag raced through high school, and have always wanted to be a professional racecar driver. I also saw how little money was to be made so decided to put that off until I could afford it as a hobby.

Fast-forward a few years (decades I guess) and I've always been in love with everything cars. I have a decent job, a family and I'm on my way to be a spectator at a race I've been following almost since it's inception. It's February 2021, and I feel an excitement I haven't felt in a long time. Do you think you know what's going on here?

If you said taking a selfie, you'd be wrong. I'm trying to figure out how to convince my wife that she doesn't need her comfy SUV anymore. Racing is in my blood and man does that bug bite hard.

Step 1) Strip it down.

There's so much plastic!

But even more copper!

The wiring weighs nearly 200 lbs and is as big around as my.... forearm.

ah.. there we go!

 

[Pharr]

Step 2) the roll cage

This car is a unibody. The traditional method for building a cage would be to plate the entire "frame" and tie into that. I'm taking a slightly different approach and creating nodes where the existing unibody has increased strength. I'm attempting to take advantage of the added strength of the unibody (lol), as well as keep me safe. The unibody has different thickness sheet steel in different locations ranging from multiple plated 1/8" to "staring at it with a welder burns a hole in it" thin. From some VW literature:

All of the dark blue is 1/8" or double and some places triple stacked (spot welded and glued)
In the pink there's a 2" x .120" door crash bar that's going to get tied into the cage & boat sides
The rest is thin or super thin and some double stacked places as well.

going for main hoop + a-pillar to floor style-o-cage

better fit up, better weld

I promise they all look like this.

yep, there's a bend in a bad place here. This will be addressed and tied into rear bumper/suspension, etc. The sandwich plates are sitting right above the "frame", and a unibody crossmember, and a suspension crossmember beneath that.

I plan with blue tape

A dash bar to tie into suspension supports

like this!
p.s. my battery is cooler than yours.

don't forget the gussets!

basically a roller now.

 

[Pharr]

Driveline:

The rear axle had an option for a locker from the factory, one of the few things this car didn't have. However, the ring gear is roughly the size of a waffle. I opted for a ford 9" housing front and rear.

The biggest issue I will run into is fitting a housing within the confines of the stock location.. The front was wedged in there with zero additional room, so anything would have to be below the subframe, not ideal. The rear seemed fairly simple, but I can't live with that. I started thinking of ways to make it more complex - because that's how to make this easier on myself . While mocking up suspension geometry and trying to figure out that math, it hit me! The rear upright has links and brackets all around it, making brake caliper location somewhat difficult. My solution: inboard brakes.

My initial plan was to replace the third member where it sat. There appeared to be enough room for everything, even given the size and axle centerline difference:

I can make this work...

and then came my best friend.. Mr. Over-complicate a simple solution:

This is looking at the diff from the left side of the car, it is in the only place where the driveshaft would clear all of the crossmembers, etc.. and the brake rotors wont work right here. A few iterations of the suspension design later, I realized that the driveline angles won't work with the third member here anyways. The only other place it will fit without driveshaft and axles hitting things is below the subframe.

shit that hangs down low. :(

But I think we can make this work. Here you can also see some suspension links going in.

4 piston calipers and 13.5" two piece rotors mounted inboard. Are we taking bets on how soon I snap the axle?

Now I knew the front diff was going to hang under the subframe, so didn't have to re-do anything.

mocking it up.

Then fitting it up..

 

[Pharr]

...then I fuckin' borked it so lets start over.

ezpz.

Now in parallel, I'm sorting out things like suspension geometry, paint scheme, and wiring. This car has two ECUs from the factory (and 15-20 other control models depending on options). They each control a single bank and share information over the CAN bus. Things like injectors and glow plugs are directly pinned to each ECU, where things like rpm are pulled from the master (or slave) and broadcast over CAN to the other. There was also an electronics control module that was responsible for powering everything that got it's "ignition on" signal from the security control module. The security control module handled things like door locks, key on, push start, etc. If the ECU got power from the ECM, but no signal from the SCM, it will not run.

Here's some simple documentation I found:

By the way, the wiring diagram PDF if 900+ pages and just as German as you'd expect. Fuck all that, I'm using an ECUMaster PDM-16 to power everything. It has two CAN networks and am spoofing signals to trick everything into being happy.

Here's the wiring harness:

but here's what I need to keep from it:

lights, throttle, and the start button.

ok, I don't need the start button, but I'm keeping it anyways.

Here's my updated wiring diagram:

So lets make the wiring harness

It's basically a carburetor.

 

[Pharr]

The winch.

I've elected to use a hydraulic winch on this platform for a few reasons:
1) They won't burn up, or overheat and uhm.. I think that will help me in the rocks, I'll just need a co-driver with enough stamina to keep up.
2) As you'll see below, this gives me a backup hydraulic pump (and a backup to that) in the event I blow a line or something.
3) The electrical system. This car is basically a big ass computer with sensors and multiple ECUs and CAN everywhere. Any disruption to this could cause some serious negative effects, and I can't exactly run to a parts store for basically every electronic part on this thing.
3b) Powering the electrical winch would require a lot of power, not a problem in a car with two big ass batteries, but I've partnered with Antigravity Batteries and am using their H8 80ah 2000cca lithium battery. That shit is awesome, and I'm not saying that because I'm sponsored, go look at the specs and tell me it's not impressive, especially compared to lead. When talking to their tech adviser they said they didn't have any concerns running a winch for extended periods, but didn't have any test data on how it would perform. I anticipate I'll need a winch and don't want chance the battery being unhappy, see previous.
3c) This engine has no standard accessory drive, nor belts or chains. Everything that spins is coupled to a set of gears off the back of the motor:

how German.

Now the areas we are concerned with are: 1) the alternator is in the Vee and is water cooled and, according to the service manual, requires the engine be dropped to change it. I've changed it.. it's a fucking nightmare. I didn't drop the motor, it took me a week. 2) the A/C compressor, which is driven from a through shaft off the back of the factor power steering pump, which is drive from the gearset. Like mostly everything on this car, it's crammed in there. What this picture doesn't show is that it's wrapped up under the motor mount. I miiiight be able to make a secondary alternator fit here, howerver..
4) I had the hydraulic winch. Prior to stripping this down, I wheeled it (Yes, even outside of malls!) I wanted to keep the AC so I tapped into the (inadequate) factory steering pump.

cool pic #1
check out that mad flex:

So hydraulic winch it is. Working with RadialDynamics we came up with the following solution: I would replace the AC compressor with a tandem gear pump with one stage sized for the steering system, which will be a Howe servo, 10:1 steering gear, and hydraulic ram.

The second stage is sized for the hydraulic pump, however we don't want to over speed it at full rpm, so it's sized for peak efficiency at 1200 RPM. More precisely, if you look back up at the gear-set arrangement, there's 4 gears driving the factory steering pump (which will not be doing anything now, and serves as a backup in the event it is required) at a 1.6:1 ratio. At 1200 engine rpm, the tandem gear pump is running in it's peak efficiency window. There are two electric solenoids on the hydraulic winch, activating each one spins the winch in a different direction. Since I'm using an ECUMaster PDM for powering things, and it has CAN, When I hit the buttons for the winch in/out, it sends a signal to the ECUs to keep the engine at at least 1200 RPM.

Fun story, the motor mounts (like so many other damn things on this car) are not symmetric. The driver side one covers what was formerly the AC compressor and is now the hydraulic pump. The holes on the block for both the motor mount and the pump are all in a different plane and spaced in ways that made making the bracket for the pump super difficult. The pump is run off the back of the factory pump via a through shaft and coupled via a gates belt coupler. In order for it function properly, it has to be perfectly aligned. I need a 3D scanner.

It doesn't look it in the pictures, but the AC compressor is not much bigger than the hydraulic pump, ~4.5" in diameter. and tucked in very tight to everything

I cut the shaft off of the AC compressor, threw it in the lathe and machined a collar to slide on to the keyed shaft of the hydraulic pump.

So, I've got three hydraulic circuits, two active and the third is the factory system. backups for days. ezpz.

 

[Wisconsinite]

subd

 

[bdkw1]

Hell yeah, the only thing cooler would be the V12TDI.

 

[backchat]

In

 

[Pharr]

Hell yeah, the only thing cooler would be the V12TDI.

That only came in the Audi and it has a few inches longer wheelbase and a foot longer body. There was a Touareg option for a gas W-12 (basically two VR6s vee'd) that did 0-60 in less than 6 seconds ..at over 6K el bees. It didn't get exported to US and is sooooper rare $$$. I could buy the Phaeton with that motor....

hmm. now that you mention it..

 

[chaplinfj60]

sub'd

 

[FC4X4]

IFS/IRS = FWIS

You going to put $50k in portal hubs on it?

 

['84 Bronco II]

Nice to see this build over here instead of on Instagram

You'll get a lot more traffic over in General 4x4. I almost missed it because I never look at the "Other Builds" section. Austin or another mod could move it if you want.

 

[chaplinfj60]

agree in the inta gram BS, if you want actual feed back and ideas shared this is the place,

 

[Pharr]

IFS/IRS = FWIS

You going to put $50k in portal hubs on it?

Nope. Had to draw a line somewhere. I don't think portals are as legendary as they are made out to be. Sure the benefits are obvious, but the geometry required to make them work sucks, especially in how the rear articulates on this vehicle. Also, given the same track width, they reduce travel. IMO, in this instance, they aren't better.

 

[Pharr]

Nice to see this build over here instead of on Instagram

yeah I looked for the VW section, I guess there isn't one? I thought this was an offroad forum...

You'll get a lot more traffic over in General 4x4. I almost missed it because I never look at the "Other Builds" section. Austin or another mod could move it if you want.

yes please.

 

[WaterH]

sub'd

X2

 

[JohnnyJ]

Interesting. This is either a really great idea, or not.

 

[FC4X4]

Sit in the seat, with a helmet on, and then put your fist on top of the helmet. I would be very surprised if you fit, unless you're 5'4.

This is the reason most of the XJ/ZJ/WJ guys use a hybrid cage with the top halo outside.

Platform is everything with the 4600 class and this one, I just don't get.

 

[JohnnyJ]

We raced an 88 Grand Wagoneer in a local offroad series (TREC), and pushed the cage further into the backseat to make room. Our tech was much less stringent than U4.

Sit in the seat, with a helmet on, and then put your fist on top of the helmet. I would be very surprised if you fit, unless you're 5'4.

This is the reason most of the XJ/ZJ/WJ guys use a hybrid cage with the top halo outside.

 

[Pharr]

Sit in the seat, with a helmet on, and then put your fist on top of the helmet. I would be very surprised if you fit, unless you're 5'4.

This is the reason most of the XJ/ZJ/WJ guys use a hybrid cage with the top halo outside.

Platform is everything with the 4600 class and this one, I just don't get.

I fit. The body is not much larger than a Passat wagon, but taller in the cab.. it's a super low seating position. The problem will be forward visibility in the rocks. I'll address that in a later post.

As for my choice of this platform, I agree, it's everything in this class. There are numerous instances of "unless factory-equipped" that I can exploit as this car came from the factory with all kinds of neat things, specifically: I am allowed coil-overs and can mount them with a mechanical advantage. Others include the big-ass turbo and airbags and/or secondary suspension. I wanted something with fully independent suspension.. I had this.. seems adequate. It also makes like all of the torques.

Interesting. This is either a really great idea, or not.

Completely agree.

 

[BLKNBLK]

Insane build...or at least the builder is...I'm in!

 

[YotaAtieToo]

You mention boat sides, but im sure you know you can't do actual boat sides per 4600 rules?

I'm guessing you mean just plated rock sliders?

Also, nice pony tail

 

[Pharr]

You mention boat sides, but im sure you know you can't do actual boat sides per 4600 rules?

I'm guessing you mean just plated rock sliders?

I've read the rules

Stock Body... ...The exception to this rule is the allowance for rocker panel protection limited to the area between the wheel wells. You may cut into the body and/or reinforce this area. You may not interfere with the mating surface of the stock door and doorsill. The stock doorsill must be retained and unaltered.

Boat side as in cut it up to the bottom of the door.

Also, nice pony tail

Sorry bud, I'm married.

 

[YotaAtieToo]

I've read the rules

Boat side as in cut it up to the bottom of the door.

Loose use of the term, but we'll allow it

Sorry bud, I'm married.

Let me guess, she needed citizenship?

 

[Pharr]

Loose use of the term, but we'll allow it

fair enough.

Let me guess, she needed citizenship?

I did meet her in Okinawa..

 

[YotaAtieToo]

Anyway,

I'm curious to see what you do with the suspension.

I like the mentality on the cage, I did something kinda similar on a 2nd gen 4runner and unibody should be even better.

I do wonder if the bars from the b pillar to the floor might be in the way for whatever may end up back there. Fuel cell, spare tire, jack, ect.

Surprised it's passenger drop, most anything made past about 95 seems to have gone driver drop. Although the euros do their own thing.

 

[Hatz33]

What are you planning to do for engine management?

 

[Pharr]

Anyway,

I'm curious to see what you do with the suspension.

I like the mentality on the cage, I did something kinda similar on a 2nd gen 4runner and unibody should be even better.

I do wonder if the bars from the b pillar to the floor might be in the way for whatever may end up back there. Fuel cell, spare tire, jack, ect.

Surprised it's passenger drop, most anything made past about 95 seems to have gone driver drop. Although the euros do their own thing.

The bars would have been in the way of stuff, hence the bend back there.. bunch of cooling below, fuel cell behind. I had planned on putting the spare in the passenger area, Dakar style, but changed my mind. By that point the bars were were they is.

The suspension is... a little nuts.

What are you planning to do for engine management?

Fuckin' thing has two ECUs (each controls a bank). I have the software to flash whatever I want on them. Motec is the only aftermarket standalone that has the hardware capable of running a 10 cylinder diesel, but when I reached out to them, they didn't know of anyone doing it so would be total custom software and requires flow testing injectors, yada, yada, money, money, time. Stock is a pair of Bosch EDC16

Mostly everything on this car is CAN controlled (I'll edit one of the posts up there ^ for more detail on the wiring, unless you're reading this in the past, or.. wait?) I'm spoofing the electronic control and security control modules (15+ modules in the trash) with ECUMaster PDM16 so the ECUs turn on and allow the engine to run for more than 2 seconds.

 

[bdkw1]

Circling back to the portal talk. They don't really cut down on travel. Yes they make the axle shorter, but they allow you to use more CV angle in bump. Normally uptravel is limited buy ground clearance. With the portal, the CV limit might be close to the bump limit.