EXCEL 89SE Kerb Weight measurements

[Lotus-e-Clan]

Today I tried out my new 500Kg wireless weighing scale.
Bought off eBay for 89 quid. Much cheaper than the £1500 quid required for proper motorsport corner weight scales.



The weighing method involved driving off my 4 post ramp onto the 500kg scale placed on one side to weigh one corner at a time, with a dummy platform placed the other side.... swapping scales left to right for the dummy, then repeating for each axle front and rear.

I recorded 2 sets of measurements; 1) Unladen (with 1/8th tank fuel) and, 2) Laden with me (87kg) in the drivers seat.

Here is the table of results:



Highights:.

• Unladen weight worked out at 1158. 3 Kg (no A/C).
  
  Near 50:50 distribution front to rear, side to side, and diagonals (cross weights).
  
  Slight righthand bias is probably due to slightly tired OE springs on the drivers's side ..but it's still bloody good!
  
  With my 87 kg onboard, the front to rear distribution improves as the seat postion is slightly towards the rear.
  
  BHP/ton number drops 10.9 bhp with me 87 kg onboard!

These weight distributions clearly make a big contribution to the Excel's supercool driving experience.

I did the Clan corner weights after this. Lowlight; the bhp/ton drops 22 bhp with me on board! Demonstrating how modern high kerb weights, requiring motorsport-level power and torque, carry people effortlessly with hardly a hit to the BHP/ton number... but it's obscenely ungreen too!

[Sirclip]

I find that quite fascinating and informative. Thanks for the info Peter. What a natty piece of kit for so few pennies. I bet you've been wieighing all manner of strange objects.

[Lotus-e-Clan]

I find that quite fascinating and informative. Thanks for the info Peter. What a natty piece of kit for so few pennies. I bet you've been wieighing all manner of strange objects.

It was a bit of a phaff doing 2 cars unladen and laden, but I now have a reference, particularly for the Clan, to help improve the driving experience.

I have 3 sets of wheels for the Clan, so I'm keen to get them weighed. I expect the OE 12 inch wheel set to be much lighter.

Yes, also weighed my push bikes. The display has a tare button so you stand on the platform push the tare then pick the bike up! I now know my winter bike is 2.5 kg heavier than my summer bike. That said, dropping my 87 kg to 80 kg would be much more effective than losing the 2.5 kg off the winter bike! Must drink less wine and cheese!

[Hawaiis0]

Just wondering if you considered the floor inclination?

[Lotus-e-Clan]

Just wondering if you considered the floor inclination?

Yes exactly. The main reason for the scales purchace is to adjust the Clan's spring platform height to get a better corner weight distribution. Currently it's nowhere as good as the Excel! So levels were at the front of my mind when setting-up.

Happily the 500kg weigh scale platform height is exactly the same height as my 4 post lift platform height grounded.

In any case it's easy to achieve a level attitude, 'cos the scales have four adjustable feet and the 4 post lift can be adjusted higher or lower if necessary. But it wasn't necessary, I just grounded the 4 post lift and adjusted the scales feet to match using a spirit level.

On the dummy side I built a simple platform out of 4x2 studding timber leveled off with an MDF top skin, the same size as the scales (60 cm x 50 cm x the scale's platform hieght).

It was just a case of rolling the car forwards off the 4 post lift (at ground level) onto the scales and dummy. You can also drive on to the scales but best have a 2nd pair of eyes to stop you at the midpoint!

Measured some of the Clans wheels today. OE Clan 12 inch wheel and tyre = 9.7Kg. My current rear 205/55 R13 AVON CR500 motorsport tyre alone (no rim) is 8 kg! With the rim it's 16 kg.

I'll take one wheel off the Excel soonest to see just how heavy the 15 inch wheels and tyres are ...God only know how heavy a 23 in SUV rim and tyre weighs? Think of the carbon footprint!!

Would be interesting to do an SA with A/C. At one point my Excel was a tad lighter with alum rad, only one rad fan, no PAS pump or PAS tank or PAS rack (lighter manual rack fitted), I also removed the spare wheel and rear spoiler, but that was a step too far - rear went light above 90mph and would step out of line everytime on mildly moist roundabouts.

[Hawaiis0]

Would be interesting to do an SA with A/C. ...

If I'm ever back at Ripon I'll call in

[bash]

When I used to use these sort of scales for roadside checks (evenin all, is this car yours etc) besides the level ground aspect we had dummy pads for the other set of wheels so that the vehicle was level.
Bash
Dont play the slippery eel with me my lad you're nicked.
Ps stopped doing that a few years ago, too busy being retired.

[Lotus-e-Clan]

Would be interesting to do an SA with A/C. ...

If I'm ever back at Ripon I'll call in

But not on a Sunday.

Would be also interestig to do V8 conversion Bash.

But I guess the weight of the 912 DHLAs +induction stuff would somehow counter the V8's extra bank of cylinders on the drivers side?

[bash]

I agree, I am curious..... If ever Im up in Ripon with Stu ( but not on a sunday ).....
Bash

[DavidOliver]

Hola Peter K.
I have looked on e-bay to see if your scales are still available for me to buy to no avail, any suggestions?
I used to have a Pace (now ADA) mechanical kit, quite useless compared to current electronic gear.
ADA kit currently costs 230 pounds.
Hardly any garages around Malaga to do the job, and at stupid prices.

Your measurements are very interesting. any interest in trying to get 100% left to right weights on each axle, even though this might make uneven ride height look strange. Perhaps can be solved by packing above upper spring seats at the front and rear shock platforms when adjustable.

Dave the cog.

[Pete Boole]

This is all really interesting Peter! Great work. Looks like a day out in a V8 Excel, an Excel SA and a supercharged Elite SA!!

I had my LS-engined Excel on corner weights but I didn't keep the record . It was front-heavy (as you might expect) - ISTR about 55/45 front/rear - maybe a little less.

I'm keeping a closer tally of weight added/lost during this build. One of the things I've noticed is how light the Elite wheels are!

Pete

[Lotus-e-Clan]

Here's a link to the scales David (uk ebay obviously):
https://www.ebay.co.uk/itm/293412846667 ... SwAyleFOhU

If you don't have a 4 post ramp one could dig two shallow pits (60cm X 50 cm X about 15 cm deep) in the drive to place the scales for a simple drive-on set-up. Then cover the pits with boards when not in use. At £89 quid you could probably justify two scales to save the phaff of a dummy platform and swapping them over each time.

Yes Pete, I'm going to be weighing everything I put into, and take out of, my cars now. The Clan for one needs to go on a diet (me too!).

[Hawaiis0]

Just realised the Airbus A400M is weighed via 14 pressure pads at each undercarriage leg.

I only need to borrow 4!

[Pete Boole]

Just realised the Airbus A400M is weighed via 14 pressure pads at each undercarriage leg.

I only need to borrow 4!

8 - then you can lend me a set!!

Pete

[Lotus-e-Clan]

Weighed a wheel and tyre off the 89Se Excel - with Toyo 205/50 R15 (left in pic)= 16.10 kg (set 4 = 64.40 kg)

Spare wheel with ORIGINAL unused Goodyear Eagle 215/50 R15 (right in pic) = 18.20 kg (set 4 = 72.8 kg)

Smaller Toyos saving 8.4 Kg compared to a set of OE Goodyear 215's.

A significant saving of 2.1 kg in unsprung weight per corner and you notice it, particularly in accelleration. This, as well as my light flywheel, must account for the relative ease in spinning the rears, even in the dry!

God knows how much more the 225/50's weigh (that some opt to fit)?