Originally Posted by
Josh Cyrul
Brian - 10x stiffer than the difference between the stiffness between the front and rear roll stiffness?? Intersting..... So basically if you run all the same suspension geometry, shock package in the front and rear you can run a chassis that is the same stiffness as the suspension?? 10 x 0 = 0 I believe...
Yes, that would be correct if we were only concerned with roll, since you would have zero torsional moment across the chassis. However we're not just concerned with roll, we need to account for dive, squat and combinations of these with roll. Also, to provide optimum handling, even with a car with 50/50 weight bias, you almost always have differing roll stiffnesses due to the fact that the front tires see different slip angles than the rears, and under weight transfer the weight bias changes and cause the tires to provide more or less grip.
Originally Posted by
Josh Cyrul
Honestly, I've hear for years "the book says" or "the computer says" but really we are not plugged into the cars like real cars nor have the on-board computers to really record what these cars do (suspension wise, not the motor/speedo data stuff). There's a seperation between man/machine with r/c that you don't find in other motorsport so I think the drivability factor actually has to be higher for us than real motorsport can get away with.
You're definitely right. We rely on "by feel" and qualitative data far more than in most motorsports. The biggest thing we are limited by is the tires. If we were able to have reasonable tire data (i.e. lateral and longitudinal force vs. slip angle, normal force, camber angle and combinations of these), we could use kinematic modeling to design cars that made the most use of these tires. The problem is, we need to have cars that are adaptable to many tires and many tracks, which make the tires work differently.
Originally Posted by
Josh Cyrul
If I ever have the time...lol... I will make up a system to check this (I've talked about it for a few years now) as I'm sure there's a lot to learn here. BUT, I also am a firm believer that there is no set rule of what you HAVE to do to make a race car fast. I think we've seen that for years where people say you have to do this or that and a year or two the bodies, tires, motors, batteries change and everything that was the rule is now out the window!! Ask the oval community about our CEFX Lithium oval car. I was told I took the Bible of "rules" they all follow and did everything possible to destroy it and my car wouldn't work... Now they are all copying it....
As far as the data and #'s I use to design our cars... Of course I could tell you, but then I'd have to kill you...lol...
Yep things do change so fast, which is why cars have to be so adaptable. Trust me I know all about not having to conform to make a car go fast. I designed and built the suspension for our Formula SAE race car, and if you know anything about that you'll know that it's the type of race car that has the most engineering freedom out there.
I was only curious about the #'s...I was just hoping you had them because I often doubt that many manufacturers do. Kill me...haha well you could try
