Traction Weight Distribution

[David FaulknerParticipant]

The Citroen Workshop Manual is quite specific when it says ‘THE LOAD DISTRIBUTION OF EACH WHEEL IS OF GREAT IMPORTANCE IN THE MATTER OF ROAD HOLDING, BRAKING AND TYRE WEAR’ and

Load distribution is of greater importance than body heights under the hull

Now my suspension has been rebuilt front and rear and the ride heights were set as per the WM but the opportunity arose yesterday to check the weight distribution as well.

Weight distribution initially proved to be outside tolerance, but following some adjustment the weights across each individual axle are now well within the 30kg stated in the manual at 6-8kg, but front to rear is slightly outside at 35kg so can anyone confirm whether or not there is any detail anywhere to confirm what front to rear axle weight distribution should actually be?

Car drives and handles fine but, should the weight distribution be even across the car or is that even possible?

• This topic was modified 6 years, 7 months ago by David Faulkner.

[ChrisParticipant]

Hi Davy,
As far as I can see the front-rear weight distribution is a function of the design and in particular the position of the engine’s centre of gravity. So if you have equal weights left to right then that’s as good as you’ll get.
Out of interest – what did you actually measure front to back? In my opinion the Traction is a mid-engined car so it would be interesting to see how close to 50:50 it is.
Regards
Chris

[David FaulknerParticipant]

Given an overall weight of 1,143kg there is a 3.15% difference front to rear Chris with the front heavier by 36kg than the rear so not quite 50:50 but nearly.

With more time it may have been possible to set it even closer but there is always a trade off.

Having driven the car some more it does handle better.

Having seen some of the work James has carried out it may be that any car that has had major bodywork repairs like the rear floor and axle mounting point (mine hasn’t as far as we can tell) should have the weight distribution checked as well as the ride height settings.

However given the state of some of the suspension adjusting screws out there setting either is not a simple task and to acquire a modern system to do comprehensive weight distribution checks would cost a minimum of £900 looking around on the web.

[ChrisParticipant]

Hi David,

I confess that when I replaced my front springs I just set the adjusters so it looked right. There’s plenty of oil down there to stop them rusting up. I suspect the rear ones would be a different story.

I didn’t have right kit or even a flat level floor. Using the load cell kit needs a flat level floor otherwise you could spend a lot of money making things worse. I imagine anyone with a Lotus 7 will have a set.

FYI the 1948 road test in the Motor lists the front/rear weight distribution of the Light 15 as 55/45 and in 1949 their test of the Six quotes 60/40.

You’ve got 53/47 – did you measure with a full tank?

Chris

[David FaulknerParticipant]

FYI the 1948 road test in the Motor lists the front/rear weight distribution of the Light 15 as 55/45 and in 1949 their test of the Six quotes 60/40.

You’ve got 53/47 – did you measure with a full tank?

Interesting statistic Chris and thanks for sharing that.

Yes the fuel tank was at about 90% full. Spare wheel and a few other bits (jack, wheel brace, a few tools etc.) were also in the car as they stay there all the time anyway.

James has a large workshop with a nice flat floor (ex bus garage) so no problems there for us.

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