Steve

I hesitate to answer your question as others have had their knuckles rapped for discussing non-7 cars on this forum, neither have I any wish to hijack this thread, but perhaps I can get away with it if I compare the characteristics of the 20 with the 7.

The only figures I have found for the 20/4 engine I have seen quote 45bhp @ 2000rpm. This from the 3610cc 4-pot job. The normal running weight of near enough 2tons giving 22.5bhp/ton. The seven is quoted as 10.5bhp @ 2400rpm and my 7 tips the scales at 12.7cwt (both including 2 passengers & luggage) giving 16.5bhp/ton. This accounts for the 20 being at least a gear better on the hills. It does seem to have oodles of torque at very low speed and will pull cleanly from about 500rpm but it still needs the lower gears, especially on the roads encountered on the Pennine Run.

Considering it was designed around 1918-19 it performs remarkably well and is much more stable than a 7 but nowhere near as nimble. Acceleration is poor in comparison mainly due to the gigantically heavy flywheel resulting in gear changes taking around 10secs to complete. Try setting off up hill in 1st then go for 2nd. The car has stopped and is rolling backwards before the engine has slowed enough to get the next gear!

Whilst I'm on the subject of design, just take a quick glance under the bonnet of a 20/4. This will immediately dispel the myth that Stanley Edge designed the 7. The 20 was on the road long before Edge worked for Austin yet the 7 design is so similar to the 20 it had to come from the same drawing board.

Edge was a very good draughtsman but it was Herbert Austin that designed the cars.

Sorry for the ramble

Martin

.

"Edge was a very good draughtsman but it was Herbert Austin that designed the cars."

......... did I hear a sharp intake of breath?



Mike

> "Edge was a very good draughtsman but it was Herbert Austin that designed the cars."
>
> ......... did I hear a sharp intake of breath?

I hope not. I think that is a very good summary of what almost certainly happened.

David

Stanley Edge must have been more than just a good draughtsman. If you look at Sir Herbert's designs for the seven opposite page 32 of Wyatt (2nd.ed), you'll see what I mean.

Lance,

Actually those 'designs' you mention are only preliminary sketches. Sir Herbert designed the Austin Seven - Stanley Edge was what we would today call a Design Draughtsman - he did the detailed draughting and that often included elements of design / calculation, eg valve spring rate, wire thickness and number of turns.

David

I am interested to see that David had O/S bushes. However ,like him I have "tinned" bushes, on many occasions, using plumbers bar solder. Then squeeze them into position using a vice and ream. AS an added bonus it stops grease coming round the outside of the bush.I recall some years ago I had to use a Porta power hydraulic ram to push out the spring. THe ram had all sorts of fittings . I used a wedge to fit in the coil end of the spring to gain secure purchase.The other end against the chassis cross member.Perhaps your local Body or hire shop could assist..

Couldn't agree more. Although the design concept of the 7 is outstanding, there are certain details (and I guess we could all name one) which just had to be the work of a 17 year old. But, I've got into trouble for saying this before.................

David Cochrane's O/S bushes did the trick. A quick bit of fettling with a file had them shaped up and well and truly pressed in and tight. Thanks David.