This is just a guess but i think one of the benefits of the short shock on a T4 aside from a minor CG change is the shock angle. If you look at the angle on most T4 setups there laid down quit a bit more than the T3 and other cars. Which i believe would make the shock more progressive as it compresses than a shock standing up. If I'm thinking about this correctly the car would be the stiffest when it starts to roll and get softer as it rollers further.

Look at the shock angle on a 1/8 scale or 1/10 nitro car, there laid down at probably a 35-40deg angle from parallel to the ground.

Opinions?

Morning Bob, I hope all is well

This past weekend was the first time I've gotten to race since making the models for the Awesomatix A700.

As an experiment I went with a completely RC Crew Chief developed set-up with a fresh car emulating other cars in the database for similar conditions.

Due to rain delays I literally had a total of about 6 minutes of practice and haven't raced true parking lot racing in 4+ years.

The car was 95% there from the moment it hit the track! A few minor changes and the car was lined up 2nd on the grid and took the main against very stout competition.

Without a doubt this is one of the best tools out there for racers that hit new tracks or get little testing time. Basically if a set-up is in there for any car you can apply the critical parameters (RC height, ride and roll stiffness, camber gain) to your car and be "nearly there" from the moment you hit the track.

Thanks again Bob for taking the time to develop this!

Mike Slaughter

P.S. I will shoot over an update soon for the A700s with new option parts added and more set-ups.

I think the shocks are softer to begin with based on the shallow angle. As the suspension compresses the shock moves to more of a 'right angle' compared with the wishbone so it will effectively get stiffer.

Skiddins

Is there a BD7 setup? If not I'll make one for you Bob.

I've been using Rcrollcentre v162 and purchased Crewchief a while back, the numbers for roll centre seem different for the same geometry.

Hey Bob. Any update on the t4? Been a while, was wondering if you had gotten to this?

Thanks much

Dave

Got the software earlier and tried setting up a T4.

Done something to the front outer camber link settings and now it won't let me edit them or correct them.
Also doesn't properly explain what was wrong with what I did?

Just tried to add the vertical offset's for the outer link ranging from 0 through to 2mm in 0.5mm increments.

Skiddins

The thing that worries me about a user created file is the possible error tolerances. .1 mm at a hinge pin mount can throw everything else off a tad. Bob, do you plan to ever take the measurements? Are you using precision equipment to do this or are you just using a caliper?

Dave

How about the BD5WXi? :-) if a setup is available for both the BD7 and the BD5 WXi, then it's all good

Just read today your answer Bob i´ve been off for a while, thank you very much.

Great news to see that there is an Awesomatix modeled car available.

Regards!!

Sorry for not getting back sooner.

Actually the stiffness increases as the chassis rolls on the compression side. The spring stiffness relative to the wheel is a function of the cosine of the shock angle squared. The angle is measure from a line perpendicular to the suspension arm. As the chassis rolls the shock angle relative to the arm actually decreases on the compression side. That means the stiffness increases as the chassis rolls. The amount of change is very small when the shock angle is small (close to perpendicular) and becomes more prominent as the shock angle increases.

Thanks for the feedback Mike. Glad the A700 model is working well for you.

Send through the model updates and setups when ready and I'll upload them to the site.

No BD7 model yet. Would be awesome if you created one.

That is strange. I used the same module in RC Crew Chief as in RCRollCentre so they should be the same. I have verified the calculations against CAD models so I am confident the results are accurate. The camber gain values are presented differently now but the static Roll Centre position should be the same.

Someone else had said they would create a T4 model. Unfortunately I haven't received it yet. You should be able to modify the T3 model. From what I understand the main difference is shorter shocks and the shocks are layed down more. If I could get my hands on one it wouldn't take long to modify the model.

I'll keep my fingers crossed the model shows up. That's probably my biggest problem. If I could get a model for every chassis out there it would make things so much easier. That is just not possible as I don't have an unlimited budget.