General Conversion Notes

[Nev Bertwistle]

So you want to do an AWD conversion on your Focus XR5 or MK2 RS but don't know where to start, well start here.

I completed mine in 2020 and along the way bought numerous Ford & Volvo cars plus spent hundreds of hours over a 4 year period researching & collecting info on how to do the conversion. It's by no means complete and there are many ways to skin a cat but this approach has worked for me and several others in Oz so I'll explain what I know. Happy to be educated if I have something wrong or there is a better way to do it.

The reason that doing an AWD conversion on a Ford Focus is possible is because the MK2 Focus & TE Ford Kuga (C307 platform) share the same platform as the Volvo P1 chassis (and Mazda 3). Ford owned Volvo from 1999 to 2010, and the three companies shared componentry across their model lines to save costs. Chassis design, floor pans, suspension components, wiring and modules were shared across the three companies. The MK2 Focus (2005-2010) and TE Kuga (2008-2012 in UK) were the same as the 2004-2010 Volvo S40 (sedan) and V50 (wagon). There were other models shared but we'll concentrate on these ones as they are the most appropriate for an AWD conversion.

The S40/V50 were available in many variants, but the most important were the T5 (FWD) and T5 AWD ones, and these could be had in both auto and manual formats. The latter were very scarce and are highly sort after.

The MK1 or TE Kuga as we know it was released in the UK in 2008 but for Oz it only arrived here Feb 2012 and was gone by Dec 2012 to be replaced by the TF Kuga. In the UK you could get 2.5T versions in both auto & manual, but here we only got the autos. Note nothing in a TF Kuga is usable, so stay clear of them.

Setting aside the AWD gearbox for a minute, the most important thing to remember is to complete an AWD conversion you can't use just one car as a donor. An S40 T5 AWD will not give you all the bits you need, and neither will a TE Kuga. You have to take parts from both cars to get a successful result. The reason is that each model has specific parts that are both usable and unusable for a conversion, and its knowing which bits go with which bits that you need to understand.

In simple terms these are the components you need:
1. M66 AWD gearbox
2. Transfer case to take drive from the gearbox to the propshaft
3. Correct length RHS driveshaft[/list]
4. Front AWD crossmember
5. Propshaft and mounting hardware to take drive to rear diff
6. Rear crossmember
7. Rear diff/Haldex/driveshafts/wheel bearings
8. AWD Fuel tank and wiring
9. Haldex wiring

It's important to understand what you are going to end up with as there is a lot of confusion around the AWD platform. You WILL NOT end up with a rear wheel driving monster that does lurid power slides and donuts. What you will end up with is a very competent car in all conditions, especially in the wet. Thats where the AWD really shines. As for the rest of it, its very subtle.

Another misconception is that you can specify the amount of lock (and HP) to the rear wheels. Leaving aside direct Haldex control, the amount of lock is determined by the maps loaded into the Haldex electronic module. The rear diff is actually two separate mechanical components - an open diff like any rear wheel drive car and a Haldex unit bolted to the front (pinion) of the diff. Drive is taken from the output of the gearbox, goes through a 90 degree transformation via the transfer case to the propshaft which is connected to the Haldex unit. Note there is no "diff" in the transfer case, it's just a crownwheel & pinion to make the 90 degree direction change in rotation. Therefore the propshaft is always rotating when the car is moving.

The Haldex unit houses a set of viscous clutch plates and there is a small stepper motor in the unit which drives an oil pump. When the electronic module asks for drive to the rear, the pump increases pressure on the clutch plates and you get drive to the pinion and the rear wheels turn like a normal rear wheel drive car. The amount of lock is controlled by the stepper motor which in turn reacts to the maps in the Haldex electronic module. That amount of lock is constantly updated as the Haldex electronic module sits on the high speed CAN network and takes its inputs from things like throttle position, engine load & RPM, wheel speed sensors, Yaw sensor, ABS etc. There is no 70:30 or 50:50 split as its constantly changing.

Having done all the hard work you'll end up with a car every bit as good as a MK3 RS (minus the drift mode). That's a big call but I have both so can speak from experience. Of course you can't buy an AWD MK2 so the MK3 RS is the go to car and is extremely capable. It just doesn't have the 5 pot growl when you get serious.