Weight distribution

Weight distribution

Author
Discussion

sdio

Original Poster:

287 posts

128 months

Thursday 12th January 2017
quotequote all
So so since caterhams have a dedion is it better to aim on diagonally equal weights or front to back?
What does common caterham wistom has to say?

DCL

1,215 posts

178 months

Thursday 12th January 2017
quotequote all
It's up to you really. Personally, IMHO, I think the best compromise is diagonally, but that can cause it to snatch a front brake if you're one up. Balancing the front will be more of an issue with traction on the higher powered cars.

rotorwings

208 posts

124 months

Thursday 12th January 2017
quotequote all
I've been thinking about this as well.

Any opinions on my current setup? This was with a driver (too fat) and 1/2 tank of fuel.


sdio

Original Poster:

287 posts

128 months

Thursday 12th January 2017
quotequote all
rotorwings said:
I've been thinking about this as well.

Any opinions on my current setup? This was with a driver (too fat) and 1/2 tank of fuel.

Why so heavy is it a super luxury Sv or an olf ford engined car?

shrink1061

102 posts

90 months

Thursday 12th January 2017
quotequote all
He said it included fuel and driver.

That could take a 530kg S3 up quite a bit

Although! By my calculations would need a 130kg driver lol

Edited by shrink1061 on Thursday 12th January 19:00

rotorwings

208 posts

124 months

Thursday 12th January 2017
quotequote all
sdio said:
Why so heavy is it a super luxury Sv or an olf ford engined car?
It's an SV R300D with heater, leather seats, FIA roll bar and weather hood mechanism still fitted, but with an aeroscreen and no doors.

...oh, and a 97kg driver!



Tazio77

224 posts

261 months

Thursday 12th January 2017
quotequote all
I have a high power VX, Northampton Motorsport set my corner weights diagonally.

dsl2

1,474 posts

200 months

Friday 13th January 2017
quotequote all
I always set mine up with equal front weights for sprints & hillclimbs use & can't recall getting beaten much!

harry b

329 posts

173 months

Friday 13th January 2017
quotequote all
dsl2 said:
I always set mine up with equal front weights for sprints & hillclimbs use & can't recall getting beaten much!
Same for me, the part of equal front weight, not the other bits.
I have LHD with C20XE engine and moved Battery, alternator, Starter (obviously), oilpump, fire extinguisher, sumptank, fuelpump to the RHside of the car to balance it a bit more against the driver.


Edited by harry b on Friday 13th January 22:10

sdio

Original Poster:

287 posts

128 months

Wednesday 18th January 2017
quotequote all
dsl2 said:
I always set mine up with equal front weights for sprints & hillclimbs use & can't recall getting beaten much!
When you set up the fronts to be equal with you in the car how much difference in weight is there at best between the two rears?
Cheers

dsl2

1,474 posts

200 months

Wednesday 18th January 2017
quotequote all
When I say equal fronts to be honest I actually tend to put up to 10 kg more on the drivers side front as I raced a Radical too (winning two championships in two years) with most circuits predominantly turning right, from memory i(ts a few years ago now) the rear weight difference was close on 20kg heavier drivers side with the drivers side front heavier 8 to 10 kg's.

sdio

Original Poster:

287 posts

128 months

Wednesday 18th January 2017
quotequote all
dsl2 said:
When I say equal fronts to be honest I actually tend to put up to 10 kg more on the drivers side front as I raced a Radical too (winning two championships in two years) with most circuits predominantly turning right, from memory i(ts a few years ago now) the rear weight difference was close on 20kg heavier drivers side with the drivers side front heavier 8 to 10 kg's.
OK smile
So it is not possible to have left and right on both front and rear perfectly matched then
So i am on a good path,
I will let you know where my cornering weight will end up


sdio

Original Poster:

287 posts

128 months

Saturday 21st January 2017
quotequote all
Hi all so here is a little update on my set up
I am aiming for 70-75mm under the sump and 20-25 rake then optimised by even front distribution and the rear as close as possible

All this is easy to achieve but i cannot get the weight off the driver's side.
This is a LHD car.
My current set up without me in (since still testing and adjusting) is :

Front LHS(driver side) 129kg, Front RHS (pax side)126kg
Rear LHS 149, Rear RHS 136kg

Ride height is 135mm front (L&R) and 160Rear (L) 155 Rear (R)

How can i lighten up the Rear LHS and make it lighter than the Rear RHS to compensate my weight when in the car ?
Already the LHS is 13kg heavier than RHS and this is without even me in!
Cheers


May be worth mentioning,
The car has the green antiroll bar in front but not antiroll bar at the rear.
Does that matter?

Edited by sdio on Saturday 21st January 17:02

DCL

1,215 posts

178 months

Saturday 21st January 2017
quotequote all
The centre of gravity is always the same (unless you move things) so you can not transfer weight to the left or right. It pivots at the C of G, so removing weight from one wheel will also remove weight at the opposite side of the C of G (mainly the diagonally opposite wheel).

In theory, the best balance for grip (cornering) is obtained when the weights are balance across the diagonals . But as has been said, theory is not always best and competition cars that use full brakes (1G plus force) may want to balance the front at the cost of the rear (where the 0.5G traction force is much less than braking).

Edit to add

I can't understand why the front ride heights are equal but not the rear. If you are on a flat floor then they should be the same, or the chassis is bent. If the floor is not flat then 5mm is a big weight and the accuracy of your measurements will be off.



Edited by DCL on Saturday 21st January 18:47

sdio

Original Poster:

287 posts

128 months

Sunday 22nd January 2017
quotequote all
Hi,

Thank you for your explanation,
My floor is not perfectly flat, I will try again elsewhere and update my comments
Thanks a lot DCL.

sdio

Original Poster:

287 posts

128 months

Sunday 22nd January 2017
quotequote all
Hi

So i tried again on a flater surface and different set of scales and after several adustments i ended up with following which i think is good enough for now.
Ride height 133/155
Sump clearances 70
Weight distribution without me 72kg
122fwd left 128 fwd right
142 rear left, 124 rear right.
With me in it the figures should change to something like this (to be confirmed during final adjustment)
138-136
174-140

I think it is good enough..