It has been all too long since my last post so this one will cover a lot of different areas. Let’s start off with the suspension.

It was my intention all along to pull and seam weld the sub-frames and control arms. From the factory, these pieces are only spot welded in anticipation daily driving abuse. For rally, it simply won’t be strong enough. In addition to that, I’ll also need to reinforce the rear differential mount. This mount is known to be problematic in the Audi community never mind the corrosive environment the car has been in all its life.

Here you can see the mount that has begun to dissolve as well as the completed seam weld along the bottom of the picture:

Here’s a look at my first solution for the reinforcement of this mount:

There are a couple reasons why I didn’t go with this solution. First, the differential sits between those two triangular structures and actually extends beyond the rear face of the mounts. The actual distance beyond depends on where the differential sits in the slot that you can see at the top of the structure. I put in a small bend to account for this but without knowing exactly where the diff was going to end up, I didn’t know if this bar was going to interfere or not. Furthermore, this solution was surely going to be quite the gravel trap and make accessing the bolt holding everything together a big pain.

I decided to go with 2 “U” shaped pieces that sit inside the existing triangular structures. It turned out like so:

For a beginner welder, I’m happy with it. The seam welding of the 2 sub frames and 2 rear control arms took quite some time simply because of the amount of welding required but there’s not much to show. It’s a simple process, but time consuming. As a note, the front control arms of these cars are cast, but the rears are stamped – hence why only the rear 2 got the treatment. I wish I could explain why, but let’s just leave it at “Audi”.

Once the welding was done, I could paint. Paint prep and painting takes an immense amount of time, it surprises me every time. I chose a brush-on paint for the suspension that many recommend for harsh environments – POR15. POR15 requires a deep degreasing followed by a metal prep treatment. This treatment seems to give the surface a deep etching in preparation for the paint. It has to be washed off very thoroughly and even after, it will be begin to corrode the bare steel before painting. Here’s the paint process I used:

Clean with scour pad and degreaser (I used the POR15 product)

Rinse thoroughly and let dry

Spray on POR15 Metal Prep and make sure the pieces stay wet for 20 mins.

Rinse THOROUGHLY and let dry

Brush on the POR15 Paint product, wait 2-3 hours

Brush on second coat of Paint, wait 2-3 hours

Spray on Rustoleum clear coat, wait specified time and re-coat

Some pictures from the never ending painting experience:

Half way through the process, I realized that I had forgotten about the Front Sway bar. I had already used up all the POR15 that was open so I decided to do that piece with all Rusoleum spray paint. It’ll be a good comparison between the two products. Here’s the sway bar after some grinding:

The shiny results:

Finally time to put away the suspension… for now. The next steps in this category will be spending money on all new bushings and mounts for the car but there’s no point in that until I’m closer to installing it – so for now, they wait.

On to the Emergency brake assembly which will be one of this first assemblies to be put back in the car. This assembly is “non-serviceable” technically which just means that you have to get creative when re-doing it. Here is the old assembly:

The reason for messing with this assembly at all, is that the grey rod you can see in the picture is used for adjusting the tension on the brake cables. That rod is also exposed to the elements and is now a corroded useless piece of steel. You can order new components from Audi, but the assembly is held together with a deformed pin. Once I got the grinder out, you can see how it works:

Nice heat treatment eh? You can see in the above picture that the pin is non-circular which holds the pieces together. Once the two ends were ground off, it could be knocked-out. What I noticed next though, was that for some unknown reason Audi made all the inner diameters of the pieces different from one another and used a plastic insert to make up the differences. This piece was now useless so I was going to have to make my own inserts to reduce the amount slop in the final assembly.

Here’s an example of what I did. Home Depot actually makes little inserts for this and that but of course nothing with the dimensions needed. I just found the piece with the right outer diameter, drilled it out to the correct inner diameter and then cut to the thickness required before pressing in place:

Here’s the final assembly. I used a 1/4-20 bolt with a lock nut. I’m going to get my hands on a low-profile lock-nut to help slim down the assembly but it should do the trick.

Next I turned my attention to the engine bay. I needed to clean it, grind out some unnecessary pieces, weld up some holes and repaint it before the engine can go back in. The battery tray (left side of picture below) is now irrelevant as the battery will be getting relocated inside the car and the ABS brackets (right side) can be removed as the ABS system has been. The angle grinder made short work of this:

That picture above also represents a few hours cleaning the engine bay over and over to get a lot of the grime out. I found Simple Green to work great for this. I took a long break from the painting to work on the wiring harness but I’ll come back to that. Just a few weeks ago, I spent even more time with a scouring pad prepping the engine bay for painting. After cleaning, it was masked as shown here:

Primed:

Painted with clearcoat

I was again reminded of just how long painting takes. With the prep work of cleaning and masking, then the dry times between coats, it is not hard to eat up a whole day. I was mostly happy with the result using VHT Engine bay paint but it was a little cold out that day and I think the paint layer suffered. I noticed little congealed paint flecks in the spray but I was on a schedule and didn’t have time to wait and figure it out. As a result, the paint has a bit of texture in it now – oh well.

Now back to that wiring I was talking about:

The picture above shows various strands just starting to get laid out and decoded. You can see many little blue flags (masking tape) which I was using to label various pieces in anticipation for stripping out unnecessary strands. This is another project that just does not fit with the anticipated time. Decoding and stripping out wires while using the manual is a HUGE time sink. I can easily say that I spent 40+ hours pulling off old wire tape, decoding the various connectors with the manual, pulling wires out of connectors and so on. It’s a complex job that is closer to a puzzle than typical rally project work.

Here’s a shot from a good way through the work. I’ve got 3 of the main strands laid out there near the fuse panel and on the right of the picture is the bundle of wires removed from the harnesses, not to be used again.

Sifting through the wiring is an exercise in patience. I came across this one relay plug that I had marked “unused” from when I originally found it in the car:

Now I needed to know if it was necessary or not and whether or not I could cut it out of the harness. My trusty Bentley manual made no mention of it while tracing through all the wire sources. I spent about 4 hours on this one socket and had to resort to an Audi facebook group page for some help. I only wish I had done this sooner. In 20 minutes I had my answer.

This socket was not even for the coupe quattro. In cars that came before the “Auto Check System” (A system used by Audi to check various fluid levels and bulbs throughout the car) this relay communicated one very important piece of data to the driver – whether or not the engine had oil pressure. Ultimately, I decided to keep it since this could be a very useful feature at some point. A classic example of how to sink hours into a small detail of a project of this size.

With lots more work, I finally started producing wiring harnesses I was happy with:

Here you see white Vinyl labels have replaced the blue masking tape and Velcro wraps have replaced the crusty/gooey wire tape. Now, this really isn’t a position to leave your wiring harness in for use, but I wanted a flexible solution that will allow me to easily make changes later, once the harness can actually be tested on the car. Shrink wrapping the whole strand would not allow me to do that. One last shot on this showing my current status of the harness, about 80% of the way there.

You’ll notice that some of the wiring is still in black protective wrap. That’s because I decided against opening up the engine harness beyond where it passes through the firewall. This was simply to limit project scope a bit. The harness took me much much longer than I anticipated and I did this to save some time seeing as there was very little need to open up that area.

The last major area to update for now is inside the car. The floor in the driver’s side was showing some signs of rust and I wanted to cap that off. I also wanted to prep the car for the cage builder when the time comes and that means grinding down some of sound/vibration dampening material. Here again I decided to limit my scope and focus on the areas forward of the rear seats. Here’s a shot after some progress had already been made:

I used a few different tools for this job, each had their strengths. I started by using an oscillating tool with a scraping blade. This tool does a good job of getting very close to the steel body and lifting or melting the adhesive underneath. Here’s a couple shots of the progress:

and after hours more…

Then I got out the angle grinder and put on the cupped steel bristle attachment. A respirator or at least a particulate mask is a very good idea for this part. The steel bristles do a great job grinding/scraping up the remaining adhesive attached to the steel and much of it will hang in the air. The result was good:

and…

So, with much much vacuuming done and not shown here, and then two rounds of cleaning with towels, painting could be done. I didn’t necessarily have to paint at this point but it would cap off the rust and I can’t say when the car will actually be ready for paint with the cage in it so now seemed like a good time to at least lay down a primer. Primer white:

and…

which looked damn good while drying. Unfortunately, when I came back a few days later, the paint still hadn’t dried because the temperatures were so cold (and I laid it on pretty thick). This resulted in the paint soaking up some of the adhesive residue underneath and tainting the color – good thing this is only primer.

This brings me up to where the project is now with winter fast approaching. Next steps will be to nail down the fuel system, the brake lines, and installing (what!?) a few things in the engine bay. Should be good! …and cold.