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Old 01-31-2013, 04:26 AM
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protc3
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Originally Posted by Clegg
How big of a factor for a class like 17.5 or 13.5 blinky is weight on a 1/12?

I have 2 V-Dezign cars, and have been having issues getting one to work as good as the other. They are exactly the same chassis setup (springs, caster kingpin angle, preload, droop, tires...) but the main difference is weight.

The 17.5 car (the one that works quite well right now) - is @ 740gm ready to race. The 13.5 car (the one that isn't working) - is a @ almost 780. I swapped motors between cars and the 13.5 car instantly went 2/10 quicker per lap than it could in the 13.5 chassis. So something has to be up with that chassis.

The reason for the heft on the 13.5 car is the HW 1S ESC and the balance weight (10gm) needed to get the car to be balanced side to side. There were also some heavier wires on the 13.5 car for the chance I ran Mod with it. I replaced those and saved a few gm.

The 17.5 has the very light HW Justock ESC on it, and is perfectly balanced with out any lead on the chassis.

So overall my question is down to - how much of an effect should 40gm have on the handling/efficiency of a 1/12? I am going to test this by pulling the portly 1S off the car and replacing it with a Justock to match my other car (the Justock can handle a 13.5 blinky just fine).

This is more of a question if people found dropping that kind of weight transformed a car, or if it really wasn't that big of a deal.
Balance is extremely important. If the car is not balanced perfectly(this goes for any pan car) you will need to compensate by applying uneven spring tension to tweak the car. This will preload one spring more than the other just to get the car tweaked. Springs ramp up in spring rate as they are compressed so in order to get the same movement left and right with a spring preloaded on one side, you effectively have 2 slightly different spring rates on each side which will make for an ill handling car. I hope this makes sense.

Also take a look at the caster in your front end left and right. Sometimes this can get knocked off a little in a crash causing different caster angles. Shims can be ok but the turnbuckle kicks off inside of the eyelet or upper arm.
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