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Welcome to the Aston Workshop news section. This section will update regularly, enabling you to keep up to date of changes and new information relating to the Aston Workshop and the Aston Martin Marque.
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Question
I find the steering on my Aston Martin is heavy, particularly at low speeds but do not want to spoil the feel of the car. What are my options?
Answer
The Aston Martin owner has never been better served for ideas and options for enhancing steering systems. But it should also be remembered that all Aston Martin cars, from the DBS made from 1968 and DB6 Mk2 from 1969 and subsequently, have all been provided with power assisted steering as standard. So this question and answer deals with Aston Martins up to the DB6 series 1.
After market options for assisted steering are broadly divided into two, either hydraulic or electric and each have their advantages and disadvantages.
First the options for the DB4, 5 and 6 owners – these cars were fitted with a steering rack steering system as original equipment and both the electric and hydraulic steering upgrades are available for these cars.
Hydraulic systems are very well tested and reliable and have been fitted to Aston Martin, in period. In general terms, a hydraulic system provides a broadly constant effort at the wheel, irrespective of the cornering and frictional resistance. If well engineered, particularly when married with a steering rack system, they can provide a pleasant fluid feel. However, self-centring action can be affected. Consequently, it is common for the caster angle to be increased to compensate, but, if taken too far, then a steering instability can be introduced. This is manifested as a steering shimmy, which is unpleasant and if severe, can be dangerous.
Fitting a hydraulic system can be complex, time consuming and leads to a non-original look under the bonnet. However, it a standard option and a familiar upgrade for many Aston Martins.
Electric systems – these are a much more recent innovation and reflect, increasingly, the standard technology now available with current car manufacture. Electric systems invariably apply the assistance at the steering column. The characteristics can be engineered to be variable - that is they can be set up to create a constant effort or a constant level of assistance, thereby helping to retain the standard feel of the unassisted steering. They do not change the direct mechanical link between steering and road wheel. Nor in general do they affect self centring action.
However, the tendency is for such systems to accentuate the effects of lost motion, and friction in the system. Consequently, it is imperative that prior to fitment of such a system, worn components are replaced and it is well lubricated and precisely adjusted to within the correct tolerances. Other advantages of these systems are that they are largely invisible; that is, the electric servos are small and can be fitted to the steering column behind the dashboard. Hence the standard look of the car is retained. They are also relatively simple to install and have little effect on the loads on the car electrical system.
Levels of assistance can be varied according to driver preference. Being made of relatively few moving parts, they are also inherently much more reliable than the hydraulic equivalent.
Such systems are fast becoming the system of choice for steering upgrades
DB2 to DB Mk3 cars. Again there is a choice of either hydraulic or electric steering upgrades. However, the hydraulic option is particularly involved as it requires the grafting of a completely new hydraulically assisted steering box to the standard steering column, no easy job. Furthermore, there is a pronounced effect on the self centring characteristics which will not be to everyone’s liking. Nevertheless, a few cars have indeed been upgraded with such a system and it is well liked.
Of potentially far bigger interest is the availability of an electrically assisted steering system. Building on the same technology now widely found in the DB4, 5 and 6, it involves the modification of the steering column to fit a small servo motor. Early experience demonstrates how important it is to bring the steering system to fully within its original tolerances for lost motion, fluidity of use and wear in the suspension system. Furthermore, it is imperative to ensure that the suspension is precisely adjusted for tracking, and caster angle.
We have experience in fitting all of these systems and we will be pleased to quote for any who would wish to upgrade their car.
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