I was having the same question as well. So, if I sum it up, it acts a bit like the MIP Bypass pistons/valve in offroad by allowing the wheel to get back on the ground quicker?

Martin Paradis

What are the ultimate penalties of running a 2.2mm carbon frame on a car designed around 1.5mm? Does it just outweigh the lower center of gravity advantages and basically put it back similar to an MTC2? Or are there other issues that relate to the increased thickness.

The system allows the wheel to drop (or potentially rise) without the dampening. Also, if something caused the chassis to come up high enough, the active corners that are not pushing the car up would have a bit more down travel to keep their wheels on the ground.

The ultimate penalty would be that your car would no longer match the pictures :) Other than that, and assuming the screws are long enough to attach everything properly, I think you'd only have the good, bad, and ugly characteristics of a having the car on a 2.2mm carbon fiber chassis. Ie, weight, strength, flex and deformation characteristics, etc. Correct me if I'm wrong.

What things did you think might be issues?

And without the spring rate. The wheel touching the ground without supporting any of the chassis weight isn't going to make a big difference.

Thats the exact reason, why it is not a fully functional faster rebound setting in my opinion. If the shock is still compressed after a compression and the next compression is happening the shock isn't ready to absorb it through its full stroke and the upper shock mount will be pushed against the bulkhead without any resistance. But i don't know how often those repeated hits/compression would appear on a normal touring car track, that this would become an issue.

With that being said, i've driven the active shocktowers on the MTC-2 mostly on the rear. It does make a noticable difference but nothing ground breaking.

But this system for sure allows force to be transferred faster to the corresponding wheel after big compressions. The weight of the suspension & tire itself, force of the anti-rollbar and straightening force of the driveshaft don't need to overcome the rebound stroke of the shock to force the wheel into the ground. How much it really is? I don't know. The "real" shock spring will do the heavy lifting, but for sure noticable.

No penalties, Unless your Cruz or Volker you wont feel the CG.
Set everything up the same way, adjust to track conditions and race.

I tested a 2.5mm last night on low bite no spray asphalt and the car was on rails.
99% consistency and 2 new track records

Its actually gonna come down to the chassis design over the thickness.
A 1.5mm may be too aggressive for some drivers where a 2.2 or 2.5 will mellow it out enough.
Its also gonna depend on the design of the chassis. A solid 1.5 may be better then a solid thicker one.
But a solid 1.5 may not work as well as an aftermarket thicker one designed to flex differently then a solid one.

A few of us (me and a couple of other toy car racers who now work for a rc design house and a f1 team), came up with the concept of active towers a good while ago. (2015 ish as I know I mounted the test parts on a TRF418). They can be effective.

This more recent article posted a few years ago explains the theory behind them.

Some of us have been still developing Rc suspension ideas and we have got something quite different we have been experimenting with which is very different indeed, but seems even more effective. but we want more testing yet. (If only real life wasn’t so busy).

https://www.thercracer.com/2021/10/t...owers.html?m=0

If you think about it, even though the tire does not have the normal force / contact patch. It just touching and rotating on the ground still provides direction stability.

Imaging taking the RC wheel and just barely running it across the ground. You'll still get a guiding force that is consistent.

Now imaging your car with the tire momentarily losing contact with the ground. In a turn the car is slipping (slip angle on the remaining 3 tires) so as the tire comes of the ground and regains contact the vector that it was traveling is now offset lets say 5mm. It is that regaining of contact during the slip of the car that might cause instability.

Is the MTC3 made in Japan?

Yes

I got to run my car Thursday night. I built it to kit specs then some minor adjustments.
First thing I noticed was rotation. Our asphalt is like glass its so smooth and they dont spray anything on it.
Track was hot but we race into the night so temps change and cars get faster as the night cools down.

I had a slight on power push but could feel the rear brake away at just the right time to rotate.
I dropped my front springs down to 4.75 and my rears to 4.50 - car got better. but still needed a little exit steering.
I rasied the rear shocks to 3mm line and was great, no needing to add DR and scrub the nose.

First round I was on track record pace but two corner clips cost me 1.4secs giving me a 29 5:00 time - new record over the 5:02 it was.
Second round I only removed the 3rd motor mount screw leaving just the rear in - quick practice with a half charge pack and was running hot lap times.
Second round gave me the first 30 lap run on our track and another record at 30 5:08

I like how small changes show results right away. No real big swings in setups to know whether it helps or not.
Thats what got me hooked on the Schuies 8 years go. One small change and the car told me yes or no.

The main was tight with everyone on fast 29 lap qualifiers. One thing I did notice the whole night and I relate it to my wing and body mounting.
When I had cars behind me, I got aero loose mid to exit. This really caused havoc for me in the main. I was checking up, braking early and trying to get clean air but 2nd and 3rd hung close.
After some bobbles and falling back to 6th I got clean air and worked back up to 3rd. Kind of varified it wasnt the car but was my body mounting.
Gonna play with my wing to help that. Overall Im super happy with the cars first night on low bite asphalt.

This was my setup I settled with.

Does the removal of the 3rd motor mount screw affect flex or does it affect something else? (The manual makes a point to use all 3 screws and I was not sure if that we for critical structure reasons or what.)

What does aero loose mean? Just read your setup, and I think I get it. I didn't realize having traffic behind you would have that big of an effect. Very interesting!

Thanks

The motor mount is pinned so it'll stay in place on the chassis.
Removing
front -> rear screws = allow more front flex aka front grip
rear -> front screws = allow more rear flex rear bite

The Schuies we run 1 screw with no problems.
I tested a battery with just the farthest rear screw. Got the on power steering I wanted and I didnt feel the pod was a problem.
Maybe they recommend more due to their grip levels and type of tracks? Im not sure.
But for what I race on, no spray and technical, I want all the steering/flex I can get.

Its an at your own risk but Im always willing to take the chance lol.
When I go back on high bite carpet I think Ill have the 2 rear ones in for tuning since grip isnt a problem.
My local carpet is always low grip so I know I'll start with at least 2 rear screws.
Once Im happy with the car Ill try just the rear and see the difference.

I mounted the body forward so basically moved the wing forward too.
The rear would want to spin out when they were behind me.
After I went to 6th I used the straights to pass and changed my lines up a little to keep them off the rear bumper.
It felt planted again - when I passed 4th they sucked up behind me so I had to break my line to keep the car stable.
All body dynamics lol. Im running the new Pantera body too which Ive never run before. Im gonna try a couple others too.

Ah, I'm an idiot. I thought you were talking about the actual screws that hold the motor in place. (embarrassing)

This is great info, thanks for sharing/explaining!