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Old 08-01-2015, 06:24 PM
  #378  
motorcitymatt
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While waiting for the MM kit to arrive I decided to put the car on the scales using the existing layout (low grip configuration) and compare it to the MM layout (using the Facebook photo of Orlowski's car as a reference). Not that it so much matters because I am just looking at deltas here but I weighed the car with the (now obsolete) CF chassis, rear and front arms reversed with rear hubs all the way forward and no tires. I also removed the aluminum side stiffeners as they do not allow for the shorty lipo to fit in between them.

The results were surprising to say the least. This is because the F/R weight distribution with both of the layouts is almost identical! About 39.5% / 60.5% front / rear. My speculations about what the effect on the weight distribution would be were completely and utterly wrong.

A few posts back someone put Maizer's car on the scales with a similar modification to this factory kit with respect to layout. The results were similar to what I found here. I should have remembered.

This of course means that Schumacher is relying on the motor's dynamic forces under acceleration to manipulate the chassis to put more weight on the rear. Assuming the effect is substantial enough to meet our needs in terms of forward bite then they have done something quite clever. We will have less on-power steering in exchange for that forward traction but the overall feel of the car around the track and the way it handles at large will stay mostly the same. Well done.

Another thing I noticed while doing the measurements was that the battery is now sitting almost perfectly longitudinally centered on the car's center of mass. I replaced the standard shorty lipo weighing 210g with one of my LRP super shorty packs, which only weighs 138g. On the scales the F/R weight distribution of the car once again did not change but the car just lost 68g of weight.

Now I don't know if the engineers at Schumacher had intentionally designed the car with this MM configuration up their sleeve in case they wanted to add some rear grip in the future if the team/customers decided they really needed it or if this just happens to be a coincidence that they discovered while testing the idea. Either case is really interesting for different reasons.

And for those who may be considering running the MM kit without the CF top brace to save weight or add flex I really, really would recommend not doing so. The engineers are clearly relying on the chassis to transmit the forces generated by the motor under acceleration to improve rear grip so removing any of the rigidity will compromise the design. And now with the aluminum side stiffeners gone removing the top brace will probably hurt a lot more than it might help in other areas.

Last edited by motorcitymatt; 08-01-2015 at 09:37 PM.
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