Product Description
Price based on modifying customer,s own axle.. which must be in good rust free condition.. and not damaged….For outright supply please call our office.
(price based on receiving good exchange unit)
The standard rear axle is a rather simple unit which is supplied from the factory with a broad tolerance for its geometry limits.
Tracking
Factory units – 1mm Toe-out to 3mm Toe-In (Based on 16″ wheel)
This in practice can permit a 4mm tracking variation between vehicles. (4mm equals 35′ minutes or 0.15 inch)
Cambers
Factory units can be -2.1 degrees to -1.1 degrees.
Again a tolerance of an entire degree, which in vehicle geometry terms is a lot.
A front wheel drive car is very sensitive to rear geometry. Racing the 900 during 1994 and 1995 taught us just how important it was.
In reality, to achieve the correct balance for the car, we spent more time altering rear tracking and cambers (using shims) than altering the front.
We also learnt that the rear suspension deflected under extreme loads and that stiffening the key weak points of the axle gave us considerable improvements in roadholding and handling.
Six years of tuning experience on the new 900 and now the 9-3 (which still uses the same axle you’d find on the rear of all new 900 models as far back as 1994), coupled with driving thousands of miles in customers and our own cars has led us to the following conclusions:
1. The ideal tracking should be 2mm Toe-In (20′ minutes).
2. The ideal camber should be -1.0 (1 Degree negative).
These parameters give the best high speed stability, steering precision, turn-in feel, cornering ability and linear tyre wear across the entire width of the tyre.
3. The difference between a good and bad handling 900 or 9-3 can often be traced to a distorted rear axle or a bad production item having the widest spectrum of geometry limits.
The standard rear axle is not a serviceable item and requires major modification on a custom built jig (see below) to align it to our exacting limits.
We have designed and built our own jig to produce axles to our proven specification of strength and alignment, this significantly improves roadholding. A substantial fabricated strengthening section is added after realignment, to prevent future distortions and geometry changes – this is marked by a white arrow on the picture above.
You can now experience far more focused roadholding, handling and stability, by fitting our sports rear axle.