Minimum Wheelbase

[J.R.]

Have any teams that are running at or close to the 60 in wheelbase run into stability problems with their cars on straights, hitting top speeds? We ran at 64 in last year and didn't have any problems, but we were only running a 40 horse motor. Also, anyone know what VT's wheelbase was this year? Looked really small at MIS. I am new to the suspension/ vehicle setup side of things, so any help would be awesome. I have been reading RCVD and Tune to Win, but they're geared towards slightly faster vehicles. Thanks!

[Mike Hart]

We run 65 and I've had that in 6th gear which must be around 70 or 80mph and it was fine. Stability shouldn't really be affected in a straight line unless your setup is seriously off. Of course your CofG or center of rotation are more important really. If your center of rotation is miles in front of the rear wheels then you'll be having issues with twitchy handling.

[MalcolmG]

we run the minimum wheelbase, and have done for a few years, and stability is not a problem at speeds seen in competition. Around 120-130km/h it starts getting a bit scary but we only ever see that in testing

[Pete Marsh]

People race shifter karts on full size race tracks at 250 Km/H and don't seem to have a problem with what must theoreticaly be impossible for any human to control?

Pete

[J.R.]

Pete, I never saw anything that would give an indication to stating that the vehicle would be beyond human control, at least nothing with numbers to it, just the generality that longer wheelbase = more stability, so I was not sure if it was ever an issue with SAE cars.

Mike, thanks for the tips, I am just now getting into center of rotations due to slip angles etc, while reading about ackerman steering. Are you saying that we want to minimize the distance that the center of rotation advances from the rear axle in the longitudinal plane?

Thanks!