I had a feeling that was the case, but that AMR is a .020" lexan and that means that I will need a new one every two weeks. I'm going to try a Speed 8 HD Parma body with all the cutouts buzzed away and maybe set forward on the car a few extra millimeters from its suggested point, but at least its .030" lexan so it should be tough.

The latest ROAR and IFMAR rules don't allow for a lot of body tuning, mounting it forward will help a little. You could try trimming the rear spoiler a little at a time. For our little group, I doubt anyone would object if you bent a bit of lexan between 45' and 90' and glued or servo taped it into the gap between the front fenders. I don't think you will be happy with the 8HD, sorry.

I prefer the non HD Speed 8 body for steering. but the AMR-12 is better then the speed series.

It's all about balance. You may just need some weight in the front of the car. I will generally add 5-7grams to the front of the body with shoegoo and that aids in steering

I was told by a man who knows a lot more than me (he designed several championship-winning pan cars) that the new 1/12 scale cars lower control arms actually flex more than the old Associated style, and that there may be some advantage in retrofitting the old arms onto a new car, is any of this true?

I would really like to see the answer to that question. I hate to by the gen xl conversion for my gen x if another conversion is in the works.

Right now in my 1/12 I have an LRP Stock Spec V2 and LRP X12 motor, both are excellent in power production and efficiency but the motor has a bit too much natural drag brake. It can be easily driven around but I think I'm going to swap this motor-speed control combo into my touring car and try again with the 1/12 scale, what combo do you suggest?

Considering starting out in 1/12th after many years running touring car. What equipment is needed to start (apart from radio gear i have that). Best current car, fastest, most reliable, best Built easiest to drive etc. Thanks

Try the X12 1s rotor, it completes that package for 12th scale.

I think any combo can be made to work, but before you spend $$$ ask Richard about the set up. His seems to roll quite nicely and it's the same as yours.

What really is the advantage of the supposedly new battery placement in some of these retrofit kits like the 12R5.1 LiPo? If the design was meant to move weight backward or forward there had to be easier ways, as far as I can tell all that this will do is very slightly change the X and Y axis moments of rotation, while the Z axis (the one that involves the car actually rotating around a corner, would be nearly unchanged. I don't buy the explanation that the shock geometry is better, or that its stronger or anything else, I think this is a shiny new toy that Associated meant to liberate you from $150 of your cash and not really go any faster. It also is making the car longer, which totally undoes the moment-of-inertia claim by moving the heaviest bits (motor, rear tires, axle, buklheads) further from the cars center of gravity. I would spend my $150 on something that I know will make me faster, like freshly trued tires, new bearings, batteries, SiC diff balls, a balance board, or gas in my tank to go practice and test-and-tune.

I have been running the inline chassis from another MFG. since February. The car is faster in the turns. Lipo's have changed everything with these cars and I think we are still learning what is needed. Less side roll was achieved by moving the batteries towards the center but not completely centered. We also got more weight up front which helped with more steering.
Keep in mind these changes were for modified, although I think stock will benefit also. In mod there is so much power that a configuration change had to happen and this has helped.
Vegas will be a good test for all the new cars.

Steve Dunn
Indianapolis, IN USA

Unless you moved the cars center of mass up or down, it's impossible to have changed the amount of chassis-rotating force the mass of the car would exert in a corner of a constant G. What may have been changed slightly is the Y-axis polar moment of inertia, meaning that the energy that the car uses upon entering a corner to first accelerate the chassis Y-axis rotation, which once moving (twisting) the speed and inertia of the movement is slowed by your dampening and then, once maximum cornering G has been achieved for a fraction of a second, stops being relevant as the car has completely set-up and there is no movement in the suspension. At that time all of the potential energy which upon exiting the corner or slowing down will be used to uncompress the chassis back to flat has been absorbed by your springs, an energy quantity independent of the polar moment of inertia and dependent only on mass, height of the center of gravity, and cornering force. So overall, changes to that moment of inertia will mean the car requires less energy to compress itself into a turn and spring itself back from cornering forces, but the force exerted on the side spring at constant G will not be changed. Technically you could say that the reduced rotational inertia to be absorbed by the dampening system would reduce the chances of over-compressing the side spring and over-rotating, but there is no 1/12 scale car in service today that isn't far massively overdamped in terms of its pendulous motion. Another argument would be that because there is a greater inertia to be absorbed by the side dampening in a given amount of time that this could result in momentary over-loading of the outside rear tire upon entering a corner from the greater dampening, but I cant say if that momentary force is good, bad, or indifferent for the car's performance.
On the other hand, you HAVE increased the energy the car will require to rotate itself on its X and Z axis, meaning that weight transfer from front to rear will be slower but contain more energy, and the energy used to rotate the car itself will be increased, there is a tradeoff to be accounted for here, and I don't claim to know the answer but I have decent reason to think that none of these values have changed more than a few percent by turning your battery sideways and then mounting your heavy brick of a speed control, receiver, transponder, booster, or receiver pack next to it. I think I can safely say that it is not just "Less side roll is achieved" or "faster in the turns."

holy wall of text Batman, what have I done....

Evan, you're over thinking this. We don't have the kind of telemetry needed to actually measure the forces at work here. All we can do is try something and see if we get faster lap times. If Steve says he can turn faster lap times with the inline car, I believe him. I think if you could accurately measure it you would have a lower polar moment along the longitudinal axis, meaning weight would transfer from side to side more quickly in both action and recovery. That would give you better transition into and out of corners. When you concentrate the weight closer to any axis, you speed up the reactions of the vehicle. Nearly every other type of RC car has longitundinal battery placement.

I don't think hes lying, but I also don't think this is a magical formula that will transform 1/12 scale racing. I think that his potential advantage in the corners is more a result of a longer chassis with more weight on the nose that can be setup and driven with more aggression than a tiny change in the rotational moment on any axis. I guess if your going to make a chassis that can fit the battery between the servo and rear pivot, why not face it sideways?