Category Archives: 06. Front Susp, Brake and Hubs

Wire wheels: worn hub and wheel splines

Wire wheels on Turners

Many Turners received wire wheels either as a standard factory option or as a later “aftermarket” change. This was (always?) combined with a Girling Type 10 disc brake conversion at the front and required the use of special splined hubs on both axles. See page 19 of the Turner Parts Catalogue below. Turners used both 13 and 15” wire wheels.


clip_image014 Special splined hubs for Girling Type 10

Wire wheel fixation

Detachable wire wheels have a different way of fixation compared to normal disc wheels, as they are mechanically “connected” to the axle hubs in two ways:

1. In a rotational direction by means of driving splines (serrations) on the (stub) axle hubs and driven splines on the inner wheel centre.

2. In an axial way by means of a (threaded) locking nut preventing the wheel to become disconnected from the threaded axle hub.

This article will not tackle the subject of which wire wheel types have been applied over the years; see the appropriate literature for that. We do want, however, to emphasise the potential danger of wire wheel fixation systems after many years of use (and abuse) to the point where they become even highly dangerous! In addition, some guidance is provided in checking whether a wire wheel can still be safely fixed to the car.


A – Locking thread on hub (left or right hand thread).

B – Driving splines on hub.

E – Driven splines of wheel centre.

Rudge-Whitworth fixation

The system of detachable and interchangeable wire wheels has been initially designed by John Pugh around 1910 but is better known under the (company) name of Rudge-Whitworth.

The resulting standardisation of detachable wire wheel fixations in Europe dates back to the 1920’s. The basis for this standard was the load to be carried per wheel and the required bearing diameter for that, resulting in a certain cross section for the hub. Note that the wheel type designation in the standard are basically structured around the (metrical!) dimensions of (then available) wheel bearings.

clip_image002[6]  Advertisement 1912

Wear on splines and thread

Over the years the thread of the locking nut and the hub itself may wear but (even more important) the splines on the hub and in the wire wheel centre may wear to the extent that the construction eventually becomes unsafe. Therefore it is wise to regularly check them and more in particular during any XK restoration as the condition and history of axle hubs and wheels are unknown.

Four dimensions are of importance here and have to be checked:

1. The maximum allowed inner diameter of the thread of the lock nut

2. The minimum allowed outer diameter of the thread on the wheel hub

3. The minimum allowed outer diameter of the splined hub

4. The maximum allowed inner diameter of the inner wheel centre splines

Please note that wear of splines and thread is accelerated if the wheel is not fitted tightly!


Cross-section of Rudge-Whitworth hubs

The principle wheel type designation according the Rudge-Whitworth standard refers to the maximum size of an outer wheel bearing (in millimetre) which can be used with that hub. The actual hub diameter is measured across the outside of the splines on the axle hubs (not the wheel splines).

Wheel Type

Actual hub diameter

Number of splines

Spline length Long Hub





































Two wire wheel types are normally used on British sports cars: type 42 and 52. Turner opted for the smaller  Type 42 wire wheels also due to the rather limited weight of their sports cars. The (course) thread of wire wheels has a top angle of 60° and a pitch of 8 TPI (or 3.2 mm) although some earlier versions may have used 12 TPI (or 2.1 mm).

clip_image002 Alexander-Turner with 15″ wire wheels

Dimensional requirements for Type 42 wire wheels: worn or still OK?

Further to the aforementioned important testing criteria, the survey below gives specific information regarding when a splined hub, wire wheel or locking nut should be replaced.

  1. The locking nut should be checked for wear on the (internal) thread. If a cylinder with an outside diameter of 2.211” or 56.2 mm should fit in the locking nut, wear has progressed to the extent that the locking nut has to be replaced.
  2. If a tube with an internal diameter of 2.291” or 58.2 mm fits over the thread of the axle hub, wear has progressed to the extent the complete hub has to be replaced.
  3. If a tube with an internal diameter of 2.424” or 61.6 mm fits over the splines of the axle hub, the complete hub has to be replaced.
  4. If a cylinder with an outer diameter of 2.374” or 60.3 mm fits in the internally splined wheel centre, the complete wire wheel has to be replaced.

Note that the above dimensional requirements are no more than minimum requirements! As an example: wire wheel constructions fulfilling the above requirements have a remaining overlapping contact height of the splines of no more than (61.6 – 60.3 =) 1.3 mm. Although the contact surface is of course larger due to the 60° V angle of the spline and the length of the spline (here 37 mm), in comparison a new type 42 spline has a contact height of 62.3 – 59.6 = 2.7 mm, meaning that the (safety?) margin has been more than halved.

So don’t use any hubs or wheels with spline dimensions below the above given minimum requirements!

Stub axle repair Turner 950

After more than 60 years of (intensive) use the stub axles of Turner 950’s may have suffered to the extend that e.g. bearings have too much play on the axle and replacement is required. Especially those having the special Girling Type 10 disc brakes mounted, may be a candidate for stub axle replacement.


New complete stub axle/kingpin forgings (BMC part number BTA 744 and 745) are difficult (impossible) to find and used replacements may have suffered even more than the old ones you are about to replace.

Installing a new stub axle may be the solution but requires certain skills and equipment but can be done. The attached drawing could offer some guidance for this replacement: any well equipped shop could make this axle. The old axle has to be machined from the upright and the diameter and length of the machined hole and new stub axle should be matched to secure a good press-fit.

New bearings SKF 7205 (Ø 25,0 x 52,0 x 15 mm) and SKF 7303 (Ø 17,0 x 47,0 x 14 mm) should be installed and the bearing spacer (88G321) between the 2 bearings checked for correct dimensions as the correct bearing play is determined by the length of this part in combination with the castle nut adjustment. Use new washers (2A 4003) and castle nuts (51K 328).



Alexander-Turner Brake Servo

Alexander-Turner Brake Servo

The Turner-Alexander had a number of optional extras in 1959 and 1960, like Girling front disc brakes and a Lockheed brake vacuum servo: indeed an intriguing combination! Girling front disc brakes were £25 whereas for the Lockheed brake vacuum servo another £20 had to be paid.

The Girling Type 10 disc brakes are described under the Category “Brakes” and “Tuning” on this website. This document describes the Lockheed brake servo.

Lockheed 5½” Brake Servo

At the end of the 50’s Lockheed had already a number of brake servo system in their programme, but most of them based on a vacuum piston moving in a cylinder with leather or rubber piston rings. A new generation using a rubber diaphragm was introduced allowing for a more compact design, making the vacuum servo piston no longer required.

Thus the new 5½” Brake Servo version was chosen by Alexander to assist the new Girling Type 10 disc brakes that required a (much) higher pedal pressure.


There were various versions with different slave cylinder sizes: 5/8”, 11/16”and 7/8” diameter all sharing the same vacuum housing. Most probably Alexander had chosen for Lockheed servo type number 112753 with a 7/8” slave cylinder, which was an “Installation Kit” without specific applications mentioned. There was an alternative “Installation Kit” which had a later Lockheed type number 4257-064, having the same slave cylinder dimensions but a different Air Control Valve housing.


A similar Lockheed servo was later introduced on the Mk1 Cooper S models (1963 onwards). All Mini Cooper S Mk 1 models came with this Lockheed type 5½” vacuum-operated brake servo unit as standard, fitted to the RH wing valence of the engine compartment. Both end covers (dishes) and the collar of the brake servo were cadmium plated, giving an unpolished bluish-white finish. The brake servo slave cylinder should be finished in matt black.

The Cooper S brake servo looks similar to the original Alexander-Turner versions and could be used.

Spare Parts

The servo Lockheed Nº 112753 required a Major Repair Kit Nº SSB.1003 and an Air Control Kit Nº SSB.1004.

The servo Lockheed Nº 4257-064 required also Major Repair Kit Nº SSB.1003 but a different Air Control Kit Nº SSB.1002.

The Cooper S servo required a Major Repair Kit Nº SSB.1036 and an Air Control Kit Nº SSB.1002.


Lockheed Air Control Kit Nº SSB.1004


Lockheed SSB.1002 Air Control Valve kit


Lockheed SSB.1036 Repair kit. The repair kit SSB.1003 will look similar.

Girling Front Disc Brakes on Turners.

image Period Girling advertisement mentioning Turner next to all the “big guys”

In 1959 the Turner 950 BMC-A and Coventry Climax got disc brakes as a factory option. This was the recently introduced (second generation) Girling Type 10 disc brake system. Girling (part of the Lucas group) began experimenting with disc brakes on race cars in 1952. An early generation Girling  Type A solid caliper 11″ disc brakes had been used on the Triumph TR3 from 1956. Turner (as a small company) was one of the earlier adopters (1959) installing disc brakes on their sports cars. It required the use of special mounting brackets to mount the callipers to otherwise standard front hubs.

Turner front disc calipers Turner front hub

Girling Type 10 Callipers (Turner H5 and H5A)  and Mounting Brackets (Turner H6) on my Alexander-Turner 950
Turner Girling front brakes Complete Girling front brake system on Turner 950

Girling Type 10 Disc Brakes 


  • Austin Healey Sprite Factory Conversions (Sebring Sprite) from 1959 onwards
  • Berkeley Bandit from 1960 onwards
  • Turner 950 BMC-A (optional) and Coventry Climax from 1959 onwards

Girling part no Description (and Turner reference number)

  • 64032502    Calliper assembly LH   (Turner H5)
  • 64032503    Calliper assembly RH   (Turner H5A)
  • 64325873    Piston
  • 64325183    Calliper mounting bracket  (Turner H6 2x)
  • 64325186    Disc   (Turner H11)
  • 64325027    (GDB 509 – DS 5S) Pad
  • 64325418    (GDB524) Pad (alternative)
  • 64325022    Pad Retaining Pin
  • 64325009    Retaining Pin Clip
  • SP2507       Service kit callipers
image Exploded view of Type 12 calliper; Type 10 is similar

image  image

Pistons 64325873 tend to corrode after many years of use (moist in brake fluid!) and are hard to find. I had new ones made in Cr Ni steel according above left drawing. Also the pins 64325022 have a hard life and making new ones is not so difficult (see 2nd drawing). These items are both used in Type 10 and Type 12 systems.

Girling Type 12 Disc Brakes


  • Triumph Herald Oct 1961 onwards
  • Triumph Vitesse “6” 1962 onwards
  • Turner GT and Coventry Climax 1220 from 1962 onwards

Girling part no Description

  • 64032604           Calliper assembly LH
  • 64032605           Calliper assembly RH
  • Non-Girling part  Disc
  • 64325708           Pad
  • SP2529              Service kit callipers

Discs dimensions for Turner Sports 950 BMC-A and Coventry Climax from 1960 onwards

Original Girling code was 64325186 (for Turner H11)




Outer diameter

Ø 217

8 9/16”

Overall width



Disc thickness



Minimum allowed thickness


Centre hole diameter

Ø 63.5

Bolt pitch circle

Ø 87.3

3 7/16

Bolt hole (4x)

Ø 9.6


These Girling discs are no longer available. Whether Girling also provided the hubs is still point of investigation. The origin (and supplier) of the Turner hub is unclear.

Other potential Turner suppliers had different dimensions: Austin-Healey Sprite has a bolt pitch circle of Ø 81.0. Triumph (Herald, Spitfire) had indeed a value of Ø 86.6 mm, but the disc is otherwise different (overall width and diameter) and cannot be used.

The Ford Escort Mk1 1300 GT disc comes very close with a bolt pitch circle of Ø 86.4 although this is a non-Girling system.

Front Brake Pads for Turner 950 BMC-A and Coventry Climax from 1960 onwards

Original Girling part number 64325418 or GDB524(no longer available). Dimensions: 62 x 43 x 15 mm. Same part number is also used as rear brake pads on Lotus cars:

  • Elan 1.5 (1962-1965)
  • Elan 1.6 (1966–1974)
  • Elan 2+2 1.6 (1967-1971)
  • Elan 130/4 (1971-1974)
  • Elan 130/6 (1972-1975)
  • Elite 1.5 (1958-1964)
  • Elite Mk II (1961 on)

Corresponding Lotus part numbers:

  • 036J6066 (non-servo version)
  • 036J6064 (servo version)

Other brands that supply this product:

  • NU-TEXA DP46
  • EBC DP145 complete axle set
  • Bendix B300119
  • Ferodo FER DA3 FF 517

clip_image003 clip_image005 Bendix B300119

clip_image009 clip_image011Ferodo DA3 FF 517

Modification of Ford Escort Mk1 1300 GT Front Brake Discs

Ford Escort Mk1 GT discs can be made to fit with slight machining. Original Ford part number: (Ford GB) 3026E1123C/68AB1125AA; (Ford D) 1450669. This disc is used on Ford Escort Mk1 1300 GT (from 8/1969 till 11/1974). For dimensions and tolerances see Brembo drawing (below).

Other manufacturers that supply this disc type:

  • Brembo 08164310
  • Ferodo DDF 009
  • EBC D080
  • SAP motor parts BDC 1018
  • Autonational BDC 0079

clip_image007[1]Comparison of dimensions Turner versus Ford disc:




Outer diameter

Ø 217

Ø 218.6

Overall width



Disc thickness



Minimum allowed thickness



Centre hole diameter

Ø 63.5

Ø 63.1

Bolt pitch circle

Ø 87.3

Ø 86.4

Bolt hole (4x)

Ø 9.6

Ø 9.9

The Ford Escort Mk1 GT disc has a different pitch circle (about 1 mm smaller) which does not allow a direct exchange. Three possible solutions:

  1. New holes have to be drilled at the correct pitch circle Ø 87.3 mm.
  2. The holes in the Ford disc have to be enlarged from Ø 9.9 to Ø 10.5 mm.
  3. The holes in both hub and disc to be enlarged to Ø 10.0 +0.05 mm.


Girling Type 10 on Sprite Factory Conversions (Sebring Sprite)

The Donald Healey Motor Company supplied conversion parts (as per Sebring Sprite) including wire wheels and disc brakes with special Ø 8½” (216 mm) front discs and Girling callipers (1958-1961).

clip_image002 WP_20180408_16_21_53_Pro          Original front splined hubs and a pair of new replacements (as reference for Turner H12 and H12A).clip_image004 WP_20180408_16_20_17_Pro                 Dust caps  (foreground) are larger than standard B.M.C. items.  Caps are tapped home inside hub.
clip_image006                                                                                                           Original Girling ‘Type 10’ brake callipers, including pads and stub axle mounting brackets.
clip_image010                                                                                                                                      Stub axle mounting brackets for the Girling Type 10 set-up.
clip_image014 Original Girling ‘Type 10’ calliper

Alexander Front Anti-roll bar

Description of the ALEXANDER Front Anti-roll torsion bar for Turner

The Alexander Anti-roll bar system consists of a standard 11/16“ (17.5 mm) torsion bar and an additional ¾” (19.0 mm) rod for increased stiffness.

clip_image002[4] Original Alexander folder

The standard bar connects LH + RH lower wishbone (via rubber mountings) with the front end of the chassis (rubber mounted distance brackets). The ALEXANDER Anti-roll bar was available as an option for cars like the A35, A40, Sprite/Midget and some larger BMC-B engined cars from the early 60’s. Also Turner offered an Anti-roll bar as an option.

The additional stiffening bar is connected via four brackets, securing the ¾” bar to the 11/16” bar and is probably a later addition. The four brackets are branded: DEE JAY RACING.

Parts list:

  1. Torsion bar  Ø 11/16”    1 pc
  2. Suspension bracket (bar to chassis)  2 pcs
  3. Rubber bush for 2.   Ø 5/8” inner x Ø 1 1/8”outer x ¾”     4 pcs
  4. Pressure plates for 3.   4 pcs
  5. Bolt for 4.  3/16” BSF x 2”    4 pcs
  6. Self-locking nut for 5.   3/16” BSF   4 pcs
  7. Bolt (susp. bracket to chassis)   3/8” UNF (5/8”) x 4”    2 pcs
  8. Self-locking nut   3/8” UNF    2 pcs
  9. Washer   5/8” large (3D)  2 pcs
  10. Bolt (bar to lower wishbone)     5/16” UNF (3/8”) x 3”    2 pcs
  11. Self-locking nut   5/16” UNF   2 pcs
  12. Rubber bush for 10.     Ø 3/8” inner x Ø 1 1/8”outer x ¾”    4 pcs
  13. Dish for 12.  4 pcs
  14. Washer (wishbone side)    5/16” large  2 pcs


Additional Stiffening Bar:

15. Torsion bar    Ø ¾”  1 pc

16. Connecting bracket (short, centre)  2 sets

17. Connecting bracket (long, side) 2 sets

18. Bolt (for 16 + 17)    ¼” UNF x 13/4”    8 pcs

19. Self-locking Nut ¼” UNF    8 pcs