Improving handling

[Paul Nott]

I've read a lot about the handling characteristics of the A7 ,indeed its skittish  behaviour has been likened to a
'Dog sniffing out its next treat'.
My special certainly suffers from it at speeds over 50mph which can be interesting at times.
My question is, am I looking for a handling quality that's not achievable given the design constraints. 
I've recently checked the front suspension components replacing radius arm cups, worn rivets , shackles,  bushes and even fitted a double arm shocker unit.
There's no excessive play in the steering or suspension. Tyre pressures 22lbs.
Yesterday I went out for a shakedown run and was really disappointed, can honestly say that I could feel no noticable difference. 
Two items still bug me and need attention and will take another capital outlay, which I'm happy to spend but will it improve things.

1. Front tyres are old(sidewall cracks) and a mismatched pair, one Mitac the other Avon MS II

2. When I purchased 18 months ago the rear suspension had a very crude spring assister set up.
These were removed, however the suspension height dropped to the extent that when two up the tyre rubbed the arch over bumpy ground.
The body height could be pulled back up but when compressed didn't rebound.
After reading how problematic replacing the springs could be decided to fit some quality assisters purchased from Austin repro.

The big question, do you think this is what's required and If tyres and springs are replaced all will be well.
I plan to replace tyres anyway, but the rear springs fill me with trepidation!

Sorry for the long post, you views and experience most welcome.
Paul

[Bob Culver]

With the saloons, and especially the high chassis ones, much of the waywardness stems from rear axle steer effects, but from all accounts cars with flatter springs as yours are hugely improved. There was long recent discussion about laterally more positive located front axle, including referenc to use of very simple rubber packers in the shackles but no details. From various accounts old hard tyres detrimental. Modern cars and other old ones have been transformed by radial tyres. Driving any on cross tyres is a surprise to modern drivers. I do not know about specials but 50 mph in saloons calls for careful choice of surface and contours and distinct alertness. If the steering wheel is held very rigid car will wander more. There must be no hint of stiffness in kingpins etc. Many on this Forum have driven Sevens for decades and unconcsciously adapt to their curious ways.
(the possible dramatic influence of tyres was demonstrated to me many years ago. Compared with my Javelin car Iwas unimpressed by my Supe Minx, both on crossplies. I intended to progressively change to radials. As was not uncommn at the time I fiited these to the rear only. Stability is supposed to be improved. On poor surfaces at 55-60 mph the car needed as much attention as the Seven!. Radials all round were a huge improvement even compared with the Javelin. I dunno the reason. Possibly camber steer front should match the rear. Try swapping the wheels, also old one side, new the other.)

[Barry Townsend]

I had exactly the same problems with my RN and decided to replace the rear springs. It had a rudimentary spring assist clamped to the half shaft tube which I hated and still bottomed out easily
It wasn't that tricky except for removing the large securing bolt at the front, this needed a hole, about 1 1/4", in the rear floor. Fortunately my old springs came away with a few well aimed thumps and the new ones came with the bronze bushes already fitted and reamed and new pins.
It made a huge difference to the stability of the car, still nowhere near more modern standards but at least driveable.
It also made a difference to the appearance of the car, no longer did it sit down at the rear.

[austin]

Get some decent tyres, it will transform it!

The move from sidecar tyres to a set of Longstones made such a difference on our Ulster, a lot of what you describe went away.

I think they will always jump around a bit due to the lack of weight and state of our bumpy roads.

[robert regan]

hello Paul I have had all sorts of cars in the past and I have found that correct new tyres can transform the way a car handles ,go for that first,you can find yourself delving into the realms of pure fantasy when you do everything you can to solve a problem and there is no noticeable effect .good luck with it Rob.

["Slack Alice" Simon]

Just on the rear springs:   I have had my share of sledgehammering them out of the chassis members.

I wanted to change them on the Tourer, so I did the (not) recommended thing of loosening the big bolt and U bolt nuts, and driving around for a bit.

They came out easily.   I think I might have sprayed everything with diesel before doing the driving around.


The cotters on the spring pin are a fiddly nuisance, you should have at least one spare set to replace the first set you have (spoilt).   And I find them physically difficult to get at. 

Fettle them on a pin with the axle dropped so you know they will work when it is back iin position.


The other tricky bit is getting the pins out - often they have grooves worn which means you are trying to knock out something that is effectively locked into position.

I helps if you have the axle weightless on a jack so it can be slightly rattled on the pin, to find the sweet spot where it will start to move.

Moving is done using a tube puller, and/or a pin through the access hole in the backplate.  

Make sure the pin is free by rotating it before you start - if it is rusted solid in the holes it probably won't come out.

All that sounds like hard work, reading it over,   But the really hard work is, in my experience, getting the springs out of the chassis - and the driving around with the montings loose seems to work well.

[Ivor Hawkins]

I agree with Austin above, old and mismatched tyres are okay on a banger, but on your special new, matched tyres are essential.

You will not regret the investment, I assure you!

[Ian Williams]

Paul, there is no need for a special to be skitish at any speed if set up properly, ignore comments about saloons they are simply not relevant, saloons in standard form have heavily cambered springs, no lateral location and are top heavy. Things that you need to check, the first you appear to have done by removing play and wear in all the components, did you ensure the castor was correct at around 5 o 6 degrees, if not it is vital that you resolve any issues there. Next you need to ensure that you have located the axle sideways, we have discussed it many times here and there are various ways I prefer immobilising one shackle or using the damper as a kind of panhard rod. Your tyres need to match, there is no excuse for old hard mismatched rubber with some extremely good options on the market, some will have different opinions but you will not go far wrong with Longstones or Blockleys. Your rear springs sound like they should be replaced, and you need to eliminate play in the rear axle mounting pins/bushes if the back end is not right the car will steer from the rear as well. The rear springs are not hard to change if you have mechanical competence, if not entrust the job to a reputable A7 specialist. The car also needs to be properly damped front and rear, but get all the above right and it will drive straight and true at any speed.

[Paul Nott]

Do I need any specialist equipment to check camber, or am I best to take it to an Austin Seven repairer?

[David Stepney]

I agree with everything that Ian says. In the late seventies/ early eighties, I had a special. The only suspension modification was flatter springs front and rear and to ensure that all joints and bushes were in good order. It was on 4.50 x 17 tyres (they were plentiful new in those days). The car was capable (just) of an indicated 70mph given enough level road and would cruise happily at 55/60. I never had any issues with the handling and the car was  quite as roadable as a friend's J type Midget.

That having been said, all beam axled cars bump steer to a certain extent and can be quite camber sensitive. It is inherent in the geometry.

Whilst I accept Ian's criticism of the saloon, these can still be made to behave themselves well on the road by scrupulously maintaining the suspension and steering, including ensuring that the steering box has minimum free play (about an inch at the steering wheel) and is free-moving throughout its range of travel.

Tyre pressures are also important. The lighter the car, the less tyre pressure you need. My RP, running on Avon Triple Duties seems happiest with 24 psi in the front and 26 in the rear. I can't remember what I ran the special at, but it was certainly less than that.

Being light, cross winds can affect Sevens, saloons the more so, due to the perpendicular architecture.

I hope these few random observations assist.