cornerweighting question - diagonal weights vs front loadings

[Nick Woods]

A few of us are starting to do some cornerweighting and have a question for the experts on this subject. The car we are weighing has starting figures of:-

front

138.5Kg 146.5

 

173.5 198.5

Using the 'normal' diagonals formula (e.g as described here) we ended up with these figures :-

135.3 149.7

 

176.7 195.3

However, we've noticed that there is a 14.4Kg difference between the front left and the front right corners. Is this signficant ? if so what should we do about it ? If we set the front weights equal it messes up the diagonals and the rears :-

142.5      142.5

 

169.5 202.5

 

Should we follow the 'normal' formula and not worry about the front weights, or set the fronts equal and not worry about the rears or aim for somewhere in the middle ?

 

We're all still fairly new to this so please be gentle with us and use lots of simple words

 

 

 

 

Nick

Red and Black 1.6K supersport

visit Carrotland.co.uk

 

 

Edited by - Nick Woods on 26 Apr 2005 13:17:31

[Sue Dinnim]

My understanding is that the fronts should match and so should the rears.

 

There is a spreadsheet which will tell you which way to play with the suspension. I think I may have a copy somewhere if you don't have it. Drop me an email through blatchat and I will see if I can find it and send it to you.

[Jason Plato]

The problem is that with our cars there is always a a weight bias to the drivers side , unless you physically move the weight around the chassis .

 

I go for the equal fronts to maximise braking

[Nick Woods]

Duncan - the spreadsheet gave us the numbers to start with , and as Dave says you cant get the balance the same at both ends because the CofG is offset

 

Dave - thanks for that. We've never met, but I am I right to think that you're not a particularly large person ? The reason for asking is that the driver of the car in question is quite large and therefore probably has more weight on the right side of his car than on yours 😳

 

So, do you think that a 50:50 split on the front would unbalance the car too much, and/or would it cause problems with the left rear brake locking due to having a much lower weight on it than on the right ?

 

I guess the best thing is to try it and see but we'd like to get it reasonably close before he starts driving it and finds out the hard way...

 

Nick

Red and Black 1.6K supersport

visit Carrotland.co.uk

 

[Sue Dinnim]

I know you can't get all four equal but I didn't know if you had the spreadsheet.

 

Not sure if it is relevant but we got my car pretty well balanced and I am around 94kg's so no flyweight.

[Jason Plato]

I'm a lardy 94 kg on a good day and when we did my flat floor me and Graham Ford achived +/- 2 Kg on the front with a similar 18Kg variance across the rear .

[Normans_Ghost]

I started by getting weights on the seat equal to my weight. (4 sacks of taters, 2 x 1 gallon cans of fuel + 2x 4litre Mobil 1= 1 fat Verona)

 

Then set the ride heights to be equal. I went for 145 at rear, 135 at front. Measured at the point under the leading edge of rear wing and between engine mounting bolts.

 

Then got all four wheels on scales and adjusted rears to affect diagonally opposed front.

 

The fronts were exactly equal at 167kgs, the rears were 20+kgs heavier on o/s (well it would be with that fat bastard in it)

 

As far as I can tell the springs are 200 front, 140 rears. The front arb is the medium (blue?)

 

When I removed the rear ARB the car was transformed.

 

Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here

[Nick Woods]

Thanks again everyone, its starting to look like equal fronts may be the way to go, possibly with a little more weight on the FR to even out the rears just a bit. We'll give it a try and see how we get on.

 

 

 

Nick

Red and Black 1.6K supersport

visit Carrotland.co.uk