There aren't many up to the minute resources that people who like to understand chassis dynamics can access.

The Formula Ford Underground was a very useful resource, and the DSR Board still is.

Today I find that a thread concerning one of my favorite subjects (Roll Centers) has gotten a breath of fresh air.

Here's the link: http://pub6.ezboard.com/fdsrfo...op=20

Jay Novak's post on page two is what prompted me to share this today.

If you're interested in this stuff keep checking back to see if these guys shed any more light on the subject - I don't know of anywhere else where you'll find this level of technical discourse accessible.

Scott, who has more questions than answers...but enjoys the problem...except when I'm on the track and the problem gets the better of me and interferes with my enjoyment...that's the problem.

 

thanks scott!

*bookmark*

nate

 

thx for the link

 

Need more!!! Hurry up!!!

Eh...

So where's the roll centers on our cars?
5th gen hatchcrap...or your car.

 

Damn - so Jay Novak posts again, but I'm dissappointed.

Sure he said alot that I agree with - RC's a little below ground, minimum KPI. But a laundry list of important design parameters isn't really "more".

What's this got to do with us?

Those in SCCA SPU or WC...or even WCHC H1 have some latitude in chassis point location.

At typical racing ride height a DC2 has a Front RC that spends most of it's time slightly below ground. There are a couple of practical ways to keep it there all the time.

At the rear there are ways to reduce roll steer (my new big obsession is the direction in which the wheels point - Front and Rear). The Rear RC, while interesting, is a little funny in the sense that lifting the inside rear takes the Rear RC to the outboard contact patch. Could the RC's lateral movement be encouraged to converge on that point? Probably not - I'll have to play with Mitchell some more this winter. FYI - the Rear RC on these cars spends most of it's time just below ground too.

That the WC RSX's don't lift the inside rear suggests that maybe, enabled or enforced by other chassis parameters, this is for Rear RC control.

Scott, who doesn't mind the inaccuracy and imperfection in what little he's able to measure and apply...it's close enough for who it's for.

 

but is the ITR a aero car or mechanical grip car?

thanks for the link

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">...it's close enough for who it's for.</TD></TR></TABLE>

Thanks...

 

hey scott, i'm probably just missing it and making a fool of myself for asking, but what is KPI??

nate

 

Kingpin Inclination - it's the angle from the vertical of the axis thru the upper and lower balljoints in front view. Caster is the side view of the same axis. We don't get to do anything KPI on our cars, but understanding it is important. Take a pen with a clip, and a business card, and play with KPI and Caster, keeping an eye on Camber and you'll get the idea. Do this with a variety of scrub radii so that you can see that counterintuitive results are possible.

Scott, who is looking forward to the simple pleasure of driving this weekend...