In 2017 I competed in the Boness Hill Climb and took the car and passenger (Angus) over the Bealach na Ba (P/O West Coast 500, Applecross section).
I had all but decided to
sell the car in the autumn of 2017 especially after the returning from Applecross. However I met a chap called Paul Neil
McLauchlan (Vintage and Classic Workshop) who talked me though a
series of changes that could be done to the car to improve it.
Another project was born.
- Engine rebuild
- New racing gearbox
- Suspension improvements
- Hydralic brakes
- Better exhaust gas flow less bends
- Seat cusions
The engine was removed in
autumn 2017 and the following work was done.
- New cast iron block
- Light weight racing pistons
- Bespoke con rods
- Phoenix crank
- High lift cams
- Improved oil delivery
- Lightened flywheel
The gearbox was next
- Racing ratios dog box between 1st and second was obtained via Vintage and Classic workshop
Moving on to the brakes
- While the engine was being built I attended to the suspension and brakes
- New brake pedal box with balance bar, dual circuit arrangement
- Twin leading shoe brakes front and single on the rear
- New handbrake leaver
- Reservoir
- Special tooling to install brakes
- New upper wishbones to stabilise suspension at front
- Rear pan-hard rod
The hydraulic brake
installation was the most difficult job I have ever done building cars. Do not attempt this job unless you are well prepared, have the correct skills and have access to another conversion as there is nothing documented. Although the
parts were new and all were intended to produce the end result in an Austin Seven many parts had to be custom engineered to fit an Austin Seven.
- One of the biggest challenges was hacking down the rear diff casting integral brake backplates, with precision, to fit the new cast alloy backplates.
- The brake pedal had to be engineered from scratch.
- The brake pedal mechanism (pedal box) mounting on the chassis had to be fabricated from scratch.
- The handbrake had to be extensively re-engineered.
- The Bowden front suspension had to be extensively reengineered.
It looks more or less like
the car was in 2017 but I assure you it is a totally different beast.
I have never invested so much time and effort into a car build with
no visible evidence showing from outside.
Rear diff brake backplates
Special tooling had to be developed to cut the rear casting of the integral backplates to add the allow backplates.
Brake pedal
A CAD drawing was produced and sent off to a plasma cutting service in Hillington near Glasgow the parts were then assembled using brazing technique.
Pedal Box
A pedal box including balance bar was obtained from Rally Design, however this had to be mounted on the A7 chassis. Image shows cardboard model of mounting arrangement. Who needs CAD?
Handbrake
The handbrake on an Austin Seven is part of a substantial round shaft bar that links into mechanical brakes. As all that was now done away with another arrangement was needed. The handbrake was always too far away to actuate while strapped in so it needed moved closer.
The original site was used for a bobbin pully that reverses the action of the cable the original brake leaver was modified with a clevis to connect to the cable.
Suspension
The suspension was defective on two counts 1) the original Bowden independent suspension did not work well 2) The rear suspension needed a Panhard rod to maintain stability.
  |
| Bowden end plate |
The above images show the fabrication of the front suspension the cardboard simulated the mudguard mounting changes. CAD came to the rescue again with a drawing remodeling the Bowden end plates to take the upper wishbone. The drawing was sent to a plasma cutting service. I needed all 4 plates to be made to a tight tolerance.
The rear suspension had a Panhard rod added.
Link to 2019 video
Here is an Index page for the build
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