human body part weights and distributing for setup

[Rick Kirchner]

In my last thread regarding corner weights there was some discussion regarding the differences between set up weights and the actual driver in the car. That got me curious, so I did some googling and found these figures:


Trunk 55.3%
Total arms 11.4%
Thigh 21%
Leg and foot 12.4%

It's probably a bit nit-picky, but once calculated if you have the modularity in weights (mine are 10" pieces of Al/Pb/Zn anodes from a gold mine plating operation, 9 lb each) it doesn't take any longer to put some realism in the distribution.


So me in the driver’s suit and helmet come in at about 245. so that means I need 165 lbs from the pan up the seat back


30 lbs from the footbox over the battery cover


50 lbs over the extinguisher cover to the front of the seat area.


I only have about 225 lbs of weight, so I’ll takeout out of the trunk/head area.


I’m going to re-distribute what I have and then after taking weights, do one with me in the car and see how close it gets.

[dereklola]

I used plastic coated weight-lifting weights (left over from my more enthusiastic days).

Sat myself in the car complete with helmet etc, half cell of water, and read the corner weights.
Then put 20# weights in the seat area and a mixture of 10# and 5# in the foot area until they
matched the previous scale readings. Then kept the info for future sessions.

[Daryl DeArman]

I’m going to re-distribute what I have and then after taking weights, do one with me in the car and see how close it gets.

I'm curious to see what you learn. I'm guessing that you left/right and cross % are going to be really close. Your front/rear balance will show you more heavily biased to the rear with you in the car than your anode analog. Moreso, the more upright your actual seating position and the fact that you are 20# light on anodes. The more rake you run the less difference it will show.

If you have to do this solo more often than not. Don't worry about your anode analog. Get the car scaled with you in it, just as you like. Get out and record all the numbers without. Then all you have to do is duplicate your unladen numbers in the future.

[Rick Kirchner]

Daryl I have done it that way as well.

by the way, when I put the springs back on the shocks and the shocks back in the car, front weights were within 3 lb!

[S Lathrop]

At one time I did setups with a car loaded to aproximately what it would be on the track. But over time I found that to be a waist of time and effort.

What I found was that having the setup pad at the track and ready to use was way more effective than doing the setup at home. With the bias ply tires, the sizes of the tires varied too much to be able to just stick them on the car and run without checking the alignment. Also it was very useful to have the pad setup so I could check any changes that I made in the pits while running, or make changes accurately for the next session.

So my setup sheet had the numbers for the car unloaded and I calculate the loaded numbers from those values. I can do this both ways, enter the values for say ride height I want and calculate what the unloaded setup values will be. One time each weekend at the track, I might check the loaded setup setting numbers to make sure my calculations are accurate. The only numbers that really count are the numbers at the track when you are running and it is those numbers I collect. When the car is working well or is off, you really want to know what the setup numbers are. And you need setup numbers that are easy to get and are repeatable.

[t walgamuth]

The human head weighs 8 #.

[jrh3]

The human head weighs 8 #.

Not some of the racers I've run with...

[Rick Iverson]

not some of the racers i've run with...

lol

[Offcamber1]

You've actually raced against Maldonado?

Not some of the racers I've run with...

[Rick Brannon]

This is an informative thread it also settles my mind by helping me see others are having some of the same thoughts. Kudos to S. Lathrop for sharing data much appreciated.

[EYERACE]

Two 60 pound bags of concrete mix which I did not unwrap and let after a long time turn into solid lumps....lay one flat from the seat back sticking down into the leg area. The other bag sits upright on top of the first against the back of the seat. The rest I finish off using your basic barbell gym weights in varying sizes down into the footwell.