20V CQ Tidy Up

[Error404]

After the disaster of my engine machining, I needed to get on with something else to take my mind of it and make some progress elsewhere

Test fitting the 0A3 RS4 gearbox: bolted it up to my old 7A block and into position:




Test fitted the vacuum servo and modified the plug bracket to fit alongside




Test fitted the B6 S4 linkage - on top of the box, it is tight but it fits - just.




At the shifter box, the stabiliser rod and shift rod slot into place but only at the very rear limit of adjustment so they need shortening by 20mm:




Underneath the rods pass nicely over the tunnel brace:




The shifter rod fits perfectly in the tunnel but the stabiliser rod (on the right) fouls the body slightly when the gearbox is raised into place. It doesn't move, but it will rub the body with the movement of the engine and gearbox, so needs a bit of work:




Easy one first, shortened the shifter rod:




Rather than try and bend it, I decided I would cut and weld the stabiliser rod to fit, for two reasons - the rods are made out of thick wall CDS and filled with lead shot, which makes them really hard to bend accurately by hand, secondly it is really easy to get into a mess with it as a small bend at one end equals big movement at the other, BTDT with a mangled S2 linkage.

Made a jig to keep the overall shape where it needs to be:




Shortened, reshaped & tacked:








Ready to test fit, then I can TIG it up and paint it.




I also started work on the gearbox mounts. The B6 & B7 cars use a single big cradle mount for the gearbox which bolts to the back of the subframe, which obviously won't fit the coupe. On the 0A3 there are mouting points in a similar position to the 01E, so I am going to use these, as well as modify my lower chassis brace with a third mount for the gearbox. First job was to make some base plates for the mounting points:

[re2500]

Awesome work alex, some good skills going on there!! Sorry to hear about the block too

[Christophski]

Wish I had these skills.... Great work bud

[irishs2]

Wow.. nice ideas here. Liked the linkage shape keeper.

[Error404]

I finished the gearbox mounts this evening, they are pretty simple really, but still very time consuming to make.
TIG skills are improving slowly. Almost seems a shame to paint them








Fitted into place:











Bit of info on the HLD 0A3 gearbox I am using: As you can probably guess it was the T3 40/60 static bias centre diff that was the reason for using this box. It has 4.111 final drive, making it an easy fit from that perspective. It is also slightly shorter geared than the CGR/CRB box, due to the 8krpm that the RS4 pulls.

HLD Gear Ratios
1st 3.667
2nd 2.211
3rd 1.520
4th 1.133
5th 0.919
6th 0.778

Compared to CGR / CRB ratios:
1st 3.50
2nd 1.89
3rd 1.32
4th 1.03
5th 0.86
6th 0.71

Using my 245/35 18 tyres, it will give me 23.0mph/1000rpm as opposed to 25.2mph/1000rpm of the CGR/CRB. Using a 7600rpm limiter, that gives nigh on 175mph, enough for anyone I think.

It is 28mm longer than the CGR, so I have sent my propshaft off to be shortened and re-balanced. The final piece of the puzzle is the speed sensor - the 0A3 doesn't have one as the B6 and later cars use one of the front ABS sensors.
Johne has been very helpful on the electrical side, and I think I have a solution that will be as close to OEM as possible....... to be continued.

[andy10v]

Nicely done on fabbing the mounts. Looks like a lot of time fettling the shapes.

Are you now using the mig to tack, and the tig to weld? Any reason you used the tig to make them?

[Rocco]

great work Alex


why have you choosen that extrange box over the other ones that does not need propshaft mods?

by the way,i like the ratios

[Error404]

Yeah I used the MIG to tack them as it a one-hander under the car etc. Used the TIG to weld them up, mostly as it is fun, and I need the practice

[G60Rallye]

Looking good Alex. Nice job on the gearbox mounts!

[quattrostyle]

The mounts look great! (Actually I never got it why people would pay silly amounts for the OEM mounts)

[re2500]

Aaarrrrggghhhh... SKILLS ENVY!!!

[4WDrifter]

beautiful workmanship wish I lived near you- I could be your " neighbour to be avoided "

keep the photos coming

[irishs2]

Sweet metalwork. Interested in the sensor solution.

[Error404]

Small update.

So many hours with the wire brush, sand paper and scotch pads today I shot some 2k primer: it won't be a perfect finish as I really don't have the time at then minute, but as long as its not rusty again I am happy. I will rub down over the next few days and hopefully shoot the colour and laquer next week. The it can all go back together again, boy am I looking forward to that point.




More wiring - I also finished the heater box side of the climate control harness. I have tried to make it plug & play as an OE RHD climate harness would have been. I have used OEM connectors and correct wire colours so in future my job can be understood





There is no upper mount on the A4 motorised heater box for the mounting bracket, so I cut the section off my old heater box an glued it on - fits just nicely now:




I also decided to give it a go with the old AAN block kindly donated by Pix. It had some sever corrosion in the water jacket, and some severe pitting in the deck around the water channels, probably caused by running pure tap water in the cooling system in it for a long period of time. Anyway, again me and wire brush have been busy. Then I saw online that you could use molasses to remove rust - I thought a total immersion would be the only way to get the scale & corrosion out of the water jacket, so I took a punt and bought 10L of the stinky stuff from my local horse feed shop. They thought I was nuts
We will see how it works in a few days when I pull it out. Shame I never got a before shot, but I am sure Pix will testify to it looking like he'd just dug it out the ground Thanks again mate



I'm not going to list what I still need to do to get it ready for ADI, as it is a LOT. Suffice to say I am unsure if it will be done by then

[irishs2]

Good show, some of that looks very familiar.

I am very interested in how the block turns out.