AWD to RWD and back again ?
 

I have been working in the states for a while and on my way back I picked up an American Car magazine to read on the way back and noticed this article which I thought might be of interest to someone.

Converting a Subaru Impreza to rear-wheel drive can be done in a number of ways. The two most common solutions involve either completely locking the stock center differential, then removing the front axles, or by swapping out the center differential for one like the Design Craft part. Typically, a center differential is locked by welding the spider gears into a solid mass, which is not particularly reversible procedure, Next, the front axles must be unbolted from the stub shafts in the hubs, and the axles removed from the transmission.
Locking the centre differential is key, if left to its own devices in a situation where the front axles were removed, it would just spin freely, sending all the engines power to the unmotivated front wheels. The viscous coupling would make an effort to shift some of the power to the rear, but ultimately would either seize or grenade.
In contrast Design Craft claims its center diff can be installed by the average mechanic in about half an hour. Replacing your stock diff and viscous coupling should take about the same. By disabling power to the front axle within the centre diff, there,s no need to remove any other parts, and converting back and forth between AWD and RWD is a snap.
The rub, of course, is the rear output shaft was only designed to handle half the stock engines power. Put all the power through that shaft, then nearly double the stock output and you have one very stressed output shaft.
After several successful drift outings, the output shaft finally snapped.

Is it really as easy as this ?

The company website mentioned is
Design Craft Fabrication
www.DesignCraftFabrication.com

I am interested to read peoples opinions on this

Gavin

when on safari here in kenya recently in a Suzuki Jimny, the shaft connecting the gearbox to the rear wheels broke. the car runs 2WD to the rear wheels normally, so i simply removed the shaft from the gearbox to the rear axle, put the car in 4WD and presto i was running front wheel drive.

Rear diffs designed to take what, say 150 bhp as it's a round number. What happens when you put 300bhp through it continually?

Would be nice though, I do like stupidly powerful rear wheel drive cars....

you just sit there spinning the wheels in a rather fantastic manner....ever driven a 2wd 400bhp cossie?

I have....wheelspin is an understatement :D

My point was more what happens when you put 300bhp thro a diff designed for 150bhp. The wheels spin merrily then they grip and the diff breaks.

ok ok the suzuki i was driving would put through 80 horses on a good day through 1300 cc of pure jap power

yes, no doubt it would wear out alot quicker...or break - like the output shaft mentioned above.

Seems strange about the viscous couplings though. I have seen Range Rovers (old shape) fitted with the Borg Warner Type Transfer box (viscous coupling - no diff lock like the majority of range rovers/defenders have). Where by removing the front propshaft made no difference to the drive via the viscous coupling in the transfer box. I suppose different car, different gearbox. But the basic drive is the same, so perhaps the viscous unit on the scoob could be replaced/modified with one that isn't so fussy?

then again...why not just fit a DCCD ;)

my shaft broke because i drove into a pile of rocks in the kenyan bush!