Ferrari 488 Evo Challenge @ Road America

Toonces · Aug 8, 2020

Ten-lap race setup for Kunos' newer-than-new Ferrari 488 Evo Challenge. This being a 'Cup' car, it's lacking many variables (no brake balance, for instance), so there isn't a whole lot to work with. Consider this a 'preliminary' setup until I figure out why it needs hellish amounts of negative camber, why I couldn't dial out massive high-speed understeer (it plows like a John Deere) and why sucks gas like it's 25 cents a gallon. Fabulous sfx however!

Why I test at Elkhart Lake. 1. It doesn't have any stupidly slow hairpins or chicanes, which interfere with repeatability; at least the way I drive. Spa would be ideal if it weren't for that ugly, contorted chicane at the end of the lap. 2. The Carousel. Unlike the Nordschleife's Karusel (tight and lumpy), RA's Carousel is the closest thing you'll find to a high-speed, steady-state skid pad (or 'pan' as they call it in Blighty). It will give you an indication of absolute grip, with numbers you can compare, car-to-car and setup-to-setup (anything below 100 mph = pokey; anything over = speedy). 3. The Kink. The scariest turn in North America. Little cars will barely notice it, but big cars will make or break a lap-time depending on whether or not your setup will allow you to take it flat out.

AmazingReflex · Aug 10, 2020

Do you mean 'less' negative camber?

I found the OMI temperatures showing Outside a lot cooler than Inside so I had to reduce the negative camber I think as far as it would go to get a more even temperature range across the tyre.

I'm not that clued up on this stuff. Am I right to change camber just to equalise temperatures as the number one aim or should we be aiming for always an amount of negative camber as it aids handling in some way?

Toonces · Aug 11, 2020

Normally, with a GT3-like car (that is, a car with medium-width tires), you'd look for 5-7 deg. temp diff, across the tread (hotter on the inside) to get the max camber thrust (grip). With extremely wide tires (i.e., Indy, F1), you look for ca. 3-5 deg. With smaller bolides (like, say, the Radical SR-3). you might want to see as much as 7-9 deg. With the 488 Evo, I discovered (by lap times, a recording G-meter, and a skid pad) that it has the most grip with 9-11 degrees. So unless the tire data is off, there's a boo-boo in the suspension geometry or the nominal values.

P.S. Same sitch @ Spa. Needs lots and lots of neg camber (tires leaning in at the top) for max grip.