Originally Posted by chris moore
If you look at the centerline you'll see that the motor is not exactly centered in the car but is just very slightly off to the clamping side. That makes up for it, but as I said it was'nt exactly perfectly balanced in this configuration. I tried it with the esc on the other side but it was worse that way so this was as close as I could get.
Some may have issue with this, but when I brought it up a while back, either here or on the 1/12 thread (or both), most seemed in agreement. I've taken to balancing the main plate of the chassis with the electronics on it and ignoring the rear pod and motor. Unlike a T(axi) C(ab) we use a solid axle--regardless the weight side-to-side both tires are flat on the "road" and the rear axle is as level as your tire size is even. An extreme example would be that you could tape another motor on top of one rear tire and you wouldn't affect tweak.
What WILL affect tweak, though, is putting electronics onto the main plate in an effort to balance the rear pod out. Yes you can get the tweak to even out, but you will have different pressures on the tweak screws/springs (and this should show up even more on the "tweakless" BMI) and can manifest itself as different ride heights side-to-side. We're not talking about anything enormous here, but a difference.
In a perfect situation the rear pod would balance too but, as Brian Bodine found when he experimented with a mass-centered motor pod, it wasn't worth the effort. There was no effect on handling, it only evened up the VERY modest difference in tire wear across the rear. This wear is more easily compensated for by rotating the tires side-to-side every run or two.
When balancing I've gone on the theory that the stuff that's symetric (front suspension, hardware on the sides (hockey sticks, etc), body mounts (anything you install equal numbers of on both sides) can be left off. I've done it both ways now and obtained the same result. I do install the antenna mount as it affects placement. The IRS buttons work perfectly inserted in the rearmost hole for the battery brace. I sure wish the buttons didn't have the hole in the face--it cuts their "sensitivity" enormously. I've almost found it easier in this regard to have the front suspension mounted, etc, just to help overcome the "flat face" the hole creates on-center.
Using this method I've built 3 DB12R's now (and a CRAPLOAD of 3.2R's, a Darkside, etc, but you have to drill your holes for these) and these cars all track dead straight on or off the power as long as the diff is adjusted properly. A fact I attribute to using the Niftech alignment tool is that every time I throw a brand new car on the track I never have to adjust the trim and it drives perfectly straight hands-off every time. I've taken to counting on that--it just does. On to worrying about something else.
Now if I could just learn to drive...