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Austin A30

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Mechanical Work Diary

01/12/2009 Bought the car.

07/03/2010 Dynamo to Alternator
 • Better regulated battery charging. Means that you can have the lights, heater and wiper on at the same time!

01/02/2010 Rewire.
 • Sort out the dodgy wiring to solve numerous Electical faults.

07/03/2010 Replace the Cooling fan
 • The A30/A35 fan blade pulls air through the radiator, my car was fitted with a Mini one that pushes.

15/03/2010 Replace the Roof lining
 • The old roof lining was missing, mouldy, smelly and black.

08/04/2010 New battery [Type 075]
 • Still running with the same battery now after a decade.

14/03/2011 Downdraft to HS2 Carburettor, inc. Alterative Exhaust Manifold (For SU)
 • Better fuel economy, slightly more power, simple design and much more reliable.

26/03/2011 4x Firestone 145/80 13 Tyres
 • Lasted for over 29,000 miles

14/03/2013 4.55 to 4.2 Differential
 • Better cruising speed, slightly less acceleration (not really an issue given that 1st and 2nd gears are mostly redundant)

02/07/2014 Engine change from 948 to 1098
 • The old engine was using about 1 litre of oil per 200 miles.
 • Fully reconditioned 1098cc engine, takes the car from 36 to 47HP.

22/04/2016 New Rear Leaf Springs
 • Firmer ride and increased ride height.
 • New bushes, no clonking when going round corners.

11/05/2016 Hardened half shafts
 • More reliable and less prone to loosing teeth with the slightly more powerful engine.

21/07/2016 Radiator Re-core
 • Runs much cooler now.

05/08/2016 Rebalanced prop-shaft.
 • Removes vibrations in the drive tunnel

01/09/2016 2x Leather hides for Seats
 • Hand made by a friend for the price of a nice bottle (or two) of Scotch.

17/09/2017 XAS 621 -> UYC 765
 • New body shell.

12/05/2018 Accuspark Electronic ignition
 • Stronger spark, better fuel consumption. Better tick over

25/06/2018 New A30 gear tunnel with A35 gear’s
 • Good match for the 1098 engine.
 • Much better gear ratios, make 1st and 2nd more usable.

25/06/2018 New 3.9 Differential from Heathrow Transmissions
 • Good match for the 1098 and A35 gear ratios.
 • Much better cruising, now sits and 55-60MPH for as long as you like.

05/08/2018 Electronic Speedo made
 • Matches the gearbox and differential. Very accurate.

25/04/2022 New tyres
 • Second set of Tyres in 15 years.

Dynamo to Alternator

This simple upgrade replaces the dynamo and the Lucas voltage regulator.
The supply to the battery is much more stable and the alternator can supply more current than the dynamo.
Removal of the voltage regulator will add to general reliability of the car.


A30 Fan blade

The previous owner of my car has fitted the fan blade from a Mini. This is designed to push air through the radiator.
The A30/A35 is supposed to have a blade that pulls air through the radiator.
Fitting the wrong type will lead to overheating.



HS2 Carburettor

I moved away from the Zenith Downdraft carburettor to a more simple HS2 carburettor
The HS2 provides better fuel mix which leads to better tick-over, improved fuel consumption and slightly more power.
This is now coupled with a K&N airfilter.
This will improve the general reliability of the car.


Originally the 948cc Austin A30/A35's would have had a 4.875 or 4.55:1 ratio differential.
By reducing the differential ratio you can get higher cruising speed and lower engine revs.
The trade-off being less pulling power at lower speeds.
When I had the original 948cc engine I moved from a 4.55 to a 4.22 diff. After upgrading to the 1098 engine (and A35 gears) I moved to a 3.9:1.
The 3.9 differential would put a lot of stress on the engine if you were towing. However as I am typically lightly loaded it works really well.
I purchased my 3.9 diff from Heathrow Transmissions, I would certainly recommend them.

You can see the improved cruising speeds from the graph below.

At 3500RPM, comfortable cuising speed, 4.55 = 52MPH. 3.9 = 61MPH.


Origionally the A30/A35 would have been fitted with 5.20 x 13 Crossply tyres.
There are two common choises for radial tyres on the standard rim. 145 x 80 R13 or 155 x 80 R13.
You can see the effect on the overall speed below.

Rear Leaf Springs

The old springs were sagging and the rear height was quite low
The previous owner had obviosuly used an incorrect size leaf spring pin and had welded it to the chassis.
This was ground out and the spring and bushes replaced. Overall ride height rose by about 7cm


948 to 1098 engine replacement

The old engine was worn and tired. Having won 1st prize in the national rally rafle of £200 it was put towards a new engine.
Out with the old and in with the new.
For more images please see the gallery



Vinyl to leather seats

A friend took away an old vinyl seat and reproduced a leather one based on that template.
One Christmas break to make the front ones and the following Christmas to make the rear ones.


Electronic Distributor

Full distributor and coil pack from Accuspark.
The kit comes with the Distributor (vacuum type D25), coil, plugs and leads.
This pack gives better reliability and a stronger spark than standard points, better fuel economy and better idling.



Re-cored radiator by Berkshire Radiators.