MY DAX MK3 STEERING UPGRADE: To Corsa B EPAS and Quaife Rack Current MK4 Spec.

[Bannon]

My Dax Cobra is a Mk3. I've owned it for around 18 months and it was built by a retired aircraft engineer colleague of mine. Chassis ordered in 1990, finally SVA'd in 2003. The result? A VERY low mileage, but old-spec DAX. My dream car - at last - in my possession. Extracted from it's birthplace - a lock-up garage - with only 130 miles on the odometer, I carefully got it running again, MoTd, and hit the road.
I love it. It's solid, the suspension soaks up the shitty roads well. But the steering. The steering is a real disappointment. It's too heavy, it tram-lines, it bump-steers dangerously. Therefore, my current project is to remove the modified Triumph Dolomite rack, mounting points and column assembly, and replace it with the current spec which is Vauxhall Corsa 'B' EPAS (Electric Power Assisted Steering) column, with the bespoke for Dax, Quaife rack and associated parts.
So - my plans to get the fabulous DAX (previously Dave Brooks) Le Mans hardtop are shelved to make way for this upgrade. I hope my forthcoming posts are of use to anyone thinking to do the same and I'll welcome any posts, comments, advice or criticism along the way.
I'm sure this will transform my car and make it awesome to drive. Let's see.

[Bannon]

Shopping list: (all prices are approx)
Vauxhall Corsa 'B' EPAS steering column. £125.
ECU Controller Module (supplies artificial signal to the Vauxhall ECU) £20
Steering Wheel Boss. Used. £20.
Quaife Steering Rack. £600.
DAX Adaptor Kit. £125.
DAX Column Modification Service. £50.
DAX Rack Mounting Bracket (to weld to chassis). £55.
DAX Splined Shaft (long) £30.
DAX Supplied Universal Joint. (QTY 2) £100.

£1015. Plus Christ knows how much in consumables, the odd tool, odds, ends, etc. You get it.

Now - if you have Dolomite switch gear, (indicators, wipers, etc), I think you can retain tem. I have bought MK2 Fiesta stalks and loom plugs which I can fit using the DAX supplied (included in kit) adaptor fitting. I might not bother at this stage, as my stalks are working fine. Incidentally, I have rotated the whole switch assembly to place the indicators on the left side of the column - just for personal preference.

While I remember - CARBUILDER SOLUTIONS!! Neil Foreman is an outstanding engineer. I've followed this guy since I was a teenager, reading his monthly installments of his Ferrari P4 replica build every month in 'Which Kit?' mag, in awe of the standards he would strive for - and exceed - through his home build. His blog for their final 'keeper' P4 build is incredible and continues to fascinate me and I recommend you check it out. I'll dig out the link to it.

I'll take some pics tomorrow, not done too much yet really.

[Joerg]

Hi Bannon,

as i know, DAX used the steering column from the sierra in the past. They took also the switches from there.
The DAX EPAS Solution is sierra switch compatible.
Hope that helps. If you have any questions in detail - ask John Kox or Adam from DAX.

Regards
Joerg

[Bannon]

Thanks Joerg, my car is pre-Sierra column though - with Dolomite column and switches. Sierra column came a few years later.
Here are some pics of progress so far, and of the 'kit' that I have put together.

[Bannon]

[Bannon]

[Bannon]

[Bannon]

Sorry for the random order of the pics. I have two kids running riot so no time to be too fussy about things. The Shots of the new column show the DAX adaptor brackets fitted, the modified lower shaft fitted, and also the chopped-down top bearing housing which is now the same diameter as the column tube. (39.5mm approx). There is a pic of the old chassis bracket that I removed, and a pic of the new bracket which is ready to go in. You'll see that I have bare-metalled the chassis for it. In another shot, you can see that I've left a stub of square section on the chassis rail. This is where I will relocate the earth lead from the engine. If I'd cut it off I would have had to weld a new tab on, which seemed a bit pointless. I'll weld a nut inside it, cap it off and job done.

[Joerg]

Looks perfect - very good foto documentation .
Enjoy the build.

[conrod]

A couple of tips from my experience of doing this job a few months ago.

1) Before you install the column, check that the position/torque sensor is working OK and correctly centred with a multimeter. In my case, the sensor was faulty, so I was able to get a replacement sensor before completing the installation.

2) No matter how carefully you line up the steering wheel on the column spline, as soon as you drive the car it will end up offset. No problem, I thought, as I had purposefully only tightened the column nut slightly. However, no amount of tugging on the wheel and use of knees would get the wheel off - so I then had to buy a suitable sized puller!

3) Make sure you use top quality yellow crimp connectors for the power and fuse connectors. The ones from Halfords and other motor factors aren't man enough, and will pull off. I ended up ordering some online and they were noticeably heavier than the others, and crimped up nice and tightly.

4) The Corsa EPAS columns have been known to misbehave (usually sensor related, and more often the C rather than the B columns), so for safety I fitted a dashboard mounted switch to cut the ignition detect wire from the ECU. That way if it does start behaving erratically whilst driving, you can quickly disable the power assistance.


Having said all that, fitting the column using the Dax bracket was a doddle. I made things difficult for myself by deciding to move from the Sierra to the Corsa B switchgear, and it was quite an interesting experience - complicated further by the fact that I also introduced a programmable intermittent wipe relay into the equation! I'm planning to pull together a Snake Torque article on what's involved in due course.

I kept my later but non-Quaife steering rack, but certainly in terms of the EPAS conversion you won't be disappointed. I recently spent a glorious ten days throwing my Dax round hairpin bends in the Alps, and it made the experience even more enjoyable than usual.

Good luck!