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fast hot rod
09-28-2014, 08:28 PM
I was wondering if it made any difference if you scaled the car with the shocks and a axel off?

Anonymous24
09-28-2014, 08:41 PM
Yes it makes a difference

fast hot rod
09-28-2014, 08:53 PM
if you have a coil over on the right rear would you just leave that shock on

Anonymous24
09-28-2014, 08:57 PM
Absolutely. Unhooking shocks or removing components for scaling will give you inaccurate data. The car needs to be scaled just how its going to be raced. The driver needs to be in the car during this process.

DirtRacer9x
09-28-2014, 09:44 PM
This is how I personally do it. Scale car without RF and LR shocks. Why? Well I've found those 2 always threw off out scale numbers. Once the car is on the scales have a crew guy hook up LR to see How much it puts onto the LR pad. The rf just leave unhooked. Usually with the gas shocks on the rest it's not much to the pads. This is how we do it and know that the LR shock gives so many lbs to that pad. If running an aggressive Rf we do not lie having to wait awhile for the pad to get close to what it was. That's how we do it. Right or wrong don't know but it's consistent every time we scale the car while when shocks were hooked up we saw 40-120 lbs LR bite change.

Anonymous24
09-28-2014, 10:01 PM
If you set the ride height before unhooking the shock/shocks, ride height probably changed. When ride height changes, so does all your angles. You are aware that the wheel rates change with the shock hooked/unhooked. I know of other racers that scale in the manner you are describing. You can be successful scaling the car in that manner, but the information that the scales are telling you is not very accurate. Always strive to get the most accurate data you can. Doing so will help you precisely tune your race car when changes are required.

Bcollins82
09-28-2014, 11:15 PM
I was wondering if it made any difference if you scaled the car with the shocks and a axel off?

Yes, pull the LR axle out until it disengages. As far as how to scale you'll get a lot of different answers. My personal preference is scaling a car as you would race it. With driver weight, with shocks on. It is the most repeatable and consistent way to do it. You may have to wait on your shocks to settle for a bit after a change if you are running a ton of low speed rebound in the RF, but it will go back to the same numbers in a minute or two unless you have something else wrong or bound. Just shake the car to settle the suspension, don't go jumping on the bumpers and you'll be fine. But as you'll hear, there have been races won scaling with shocks hooked, unhooked, driver, no driver, full of fuel, empty tank, setting wedge with a socket under the center of the rearend, by just measuring between springs and the frame, etc, etc...

Duckhnter83
09-29-2014, 07:51 AM
I look at scaling as I want repeatable results every time I put the car on the scale. The only way to assure that is to unhook all shocks and pull a axle. I feel I should be able to roll the car off the scales bounce on it roll it back on and still have the same numbers as before. If you have shocks on this could throw your numbers off by holding weight on one tire over another along with an axle in could cause the rear to bind. The more accurate and repeatable the results are make your program consistent and more predictable with changes

TS3g
09-29-2014, 08:21 AM
At the end of the day, it really doesn't matter how you do it, as long as you do it the exact same way every time