What is the point of having your wheels splaying out on a family saloon or a city hatchback?
I gather camber helps with handling but whilst I can understand the need for a racing car to have this, why a bog standard run around?
I saw a BMW Mini convertible the other day with its rear tyres splayed out. It just looked to me as if the inside of the tyres would just wear faster than the rest. In fact it looked downright odd because the fronts had no visible camber. If it improves handling why don't all cars have it?
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Splayed in what sense?
Some cars including the Citroen BX look like they've got bandy knees when the bearings for the rear suspension arms wear.
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splayed as in the bottom of the wheel sticks out further than the top - like it would if an elephant was sat in the back seat!
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I think you mean negative camber. Positive camber is what you get on tractors.
en.wikipedia.org/wiki/Camber_angle
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oh tish, I knew I'd got it wrong.
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Yes - and I always wondered why old cars (like 1920's ish) with beam axles seemed usually to have positive camber, especially on the front (steering) ones?
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Can't be sure, but I think some old cars were positive camber to make the steering lighter. My Morgan three wheeler is positive, but is only 270 degrees on the steering wheel; lock to lock. Early three wheelers are even less - 135 degrees lock to lock.
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>> Can't be sure, but I think some old cars were positive camber to make the steering lighter.
You're quite right Sp. It's even more necessary with the very high-geared steering found in Morgans. The other thing that makes steering heavy is vehicle weight. US car makers settled on very low geared steering ratios, four or five turns from lock to lock, before power steering was generalised. It made American cars very hard work when speed or slippery road conditions induced large slip angles at either end of the jalopy.
Respectable American drivers used to be almost allergic to tyre squeal, which they felt to be the thin end of the loss-of-control wedge...
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NC answered my query on why older cars had so much positive camber on the front wheels. All to do with bearing loading IIRC.
Negative camber's there to keep the outside tyre flat to the road surface during hard cornering - it compensates for body roll (I believe!).
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>> All to do with bearing loading IIRC.
Sounds like the usual rubbish from N_C. Very few of his posts contained useful information.
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Negative camber's there to keep the outside tyre flat to the road surface during hard cornering - it compensates for body roll (I believe!).
Yup, I converted the four wheeled Morgan I had to 0.5 degrees negative from 2 degrees positive. Not worried about steering wheel effort, I've driven a rally Manta and quick rack equipped RS2000 and they both put hairs on your chest etc.
Did a lot of playing about with suspension on the four wheeled Morgan car, eventually got it where I like, roughly neutral but would oversteer and understeer on demand and left to it's own devices, would spin in (one gets oval racers to do this, less hard objects on the inside of a bend).
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The first car I had was negative camber rear, positive camber front. It looked like the rear suspension had collapsed but that was how FIAT set them up back in the mid-70's.
It was probably more obvious on a 145x13 than on modern 225/235/245+ rubber band on a 18/19/20+ wheel.
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Positive camber - Bromptonaut
