Roll centres + Rubbish saloons

[greenamex2]

Quaife did a floating axle kit for the Corolla for Group A.

What do they gain you?

[R59]

With your axle Denis, your hub flange is welded to the halfshaft. You have a small single bearing at the end of the axle tube. The shaft and the hub share a bearing, and finally, you can't tweak camber/tracking very easily with that setup, without causing premature failures.

With a fully floating setup, the hub, with it's brake disc, sits on a pair of taper rollers, or double race ball bearings, the shaft is splined at both ends and can be retained by a number of means depending on manufacturer. There is more scope for allowing small adjustments in camber etc.. without causing reliability issues.

Millions of Gp.4 Escorts can't be wrong!!

Banked oval racers use them, or should I say, can't be without them.

The main benefit is for fitting proper brakes on sturdy hubs.

Rob.

[Al Weyman]

Transit vans have them as well I believe:-)

[R59]

Only on the twin-wheelers, though that's an inherent design to withstand the extra loading.

There you go, and another reason for running them - they withstand more load than a conventional setup.

Thanks Al.

[grelley]

I have seen Corrolla rear axles cambered by heating the tops of the axle tubes and allowing to shrink, thus bending the outer ends upwards. There is sufficient play in the spider gears to tolerate this. The particular car I saw it on had run endurance races with this set up. There was a small amount of wear on the inner splines. Re the Rovers I have seen the cambered rear ends for these. The rear axle tubes were shortened, and a two peice axle shaft with a universal joint fitted near the outer end. A hollow aluminium distance peice approximately 75-80 mm long was bolted between the axle tube flange and the outer hub housing. This aluminium housing was machined at an angle at one end and this angle could be altered to adjust the amount of camber and toe in as required, depending on the angle machined into it. The Australian V8 Supercars use a similar method

[Al Weyman]

they withstand more load than a conventional setup.

I always thought this and the fact you did not shed a wheel when a half shaft broke were the primary reasons for their use.

[greenamex2]

Sounds like the potential for even more weight!

The Corolla already has substantial double row bearings so probably not such a big problem.

I might give the axle bending trick a try. The method described to me was to weld a line on the top of the casing.

Re the Rover thing. The lengths people will go to in order to get round regulation wordings!

[greenamex2]

Moving the body end of the panhard rod had a noticeable effect on oversteer.

It reduced it a bit but, more importantly, made the slide far more progressive allowing me to start drifting (ie real drifting not drifting the sport drifting) the car round the corner.

The car also rolled a little less due to the raised roll centre.

Still room for improvement but we now probably have scope to dial some of the oversteer out by reducing rear bump damping.

It is certainly convinced me that a watts linkage could be worth the extra weight, particularly given the inherent 'bump steer' built in to the Corolla rear suspension.

And judging by some of the sketches I found on my Dad's desk I suspect I wasn't going to have a choice anyway!

[phoenix]

Good news - did you see an improvement in lap times? After all, that is whate really that matters!

[greenamex2]

0.5 seconds faster than I have ever been round Mallory Park before, in less than ideal conditions.

I was also a bit closer to the faster cars than expected.

[phoenix]

Great news!

[greenamex2]

Only another second (round Mallory) to find!

[phoenix]

Well having found 0.5 of a second I should keep looking in the same direction for more improvements.

It may well be that having found a better balance (oversteer/understeer) playing carefully with tyre pressures/temperatures and damper settings will find you some more pace - maybe another half a second.

Then when you are really confident in the car the other half second will come from you braking less and going round Gerrards like a bat out of hell!