What is a "touring car?"

[JeffYoung]

I didn't say it wasn't common practice; I said it's an act of the demented.

Greg's picks are dominated by sports cars with the most powerful engine eligible. Why? Because people willing to spend coin to try to run up front understand that's the formula for success. Why would anyone do otherwise given the physics of the situation?

My proposition was that, particularly with the human beings we have at the levers of policy, a sports car is going to have an inherent advantage over a touring with the SAME engine.

K

But with all due respect, that's due to assumptions that CG is lower, that CD is lower, and that frontal area is smaller. That MAY be the case, or it may not. My gut non-scientific observation is that Miatas don't draft as well as Integras, and over 120 mphish (again, total observation bias here) the Integra has the advantage. But without numbers it is all guess work.

Which is the problem with trying to quantify difficult "effects" like aero, or torque, or "bad rear suspension" (as the owner of a live rear axle car, I frankly couldn't justify giving it a break against most stuff out there given what we can do with the rules in IT) -- it's just WAY above our skill level to do so in my opinion.

I would, however, really like to see numbers on aero, real CD x Frontal area numbers, of sedans/coupes v. sports cars. I'm sure some sports cars do quite well. I'm also pretty sure some coupes/sedans do as well.

Was at Homestead this weekend, was down there for work Friday and stayed and rented Mike VS's ITS Miata. Ran with the STL cars -- I think there were 5 dedicated STL cars. Two twin Celica GTSes, an Integra (Peter Keane?) and two Miatas. The Celicas were pretty. Peter's car is black and looks bad ass.

[Greg Amy]

...a sports car is going to have an inherent advantage over a touring with the SAME engine.

All discussions in regard to Super Touring must always, always, always divorce engine and chassis discussions. Because we can so freely swap family engines in family chassis, they may be coincidental but they are not directly related.

So for example, "the RWD Miata is not dominant because it has a lower-powered engine" or "the Honda Civic is a great car because it has a powerful engine" is an invalid discussion point. On the other hand, "the Honda Civic is a great strut chassis" and "the Miata is a great sports car option" are valid discussion points.

Engines should be adjusted by engine-related inputs/factors; chassis should be adjusted by chassis-related inputs/factors. There are crossovers, such as power-to-weight considerations and/or effects of weight on chassis, but they are otherwise parallel lines that should not meet.

I would, however, really like to see numbers on aero, real CD x Frontal area numbers, of sedans/coupes v. sports cars.

Because we have some flexibility with aero in Super Touring, I'm not that stuck on aero considerations. We add air dams, undertrays, splitters, and wings, and we lower the car to reduce the amount of underbody airflow. All go a long way toward improving - and in some case, hurting - aero, but in a generally-equitable way*.

There are other non-quantifiable; the Miata, for example, gets its factory cD numbers off the base car, which is a convertible. Yet, we allow the factory hard top, which no doubt goes a helluva long way toward improving that cD. And, related to above, the STL-compliant airdam goes a long way toward cleaning up the jelly bean nose that forces a lot of air under the car.

The one manufacturer-published aero factor that seems significant to me is frontal area. I see that as a general characteristic of the size of the hole that the car has to punch through the air.

GA

* "Hurting" meaning rear wings. Which, of course, benefit RWD cars a shat-ton better than they do FWD cars... Airdams increase drag as well but their benefits far outweigh that, and generally equitably among most cars, regardless of drive layout.

[JeffYoung]

Yeah, I agree -- I think frontal area is a more significant factor at this level of racing than CD. It seems to play out in the real world as well. My car has crappy CD, but is tiny. Seems to do ok at 120+ as a result.

Note also that I think "downforce" aero at these speeds and with these implements is a mistake. Just my opinion but whatever downforce you generate is going to be far offset by drag, which is the key thing to me from observation. For IT, and I would think STL, you want the slipperiest car possible with the smallest frontal area.

For the NSX fanbois (I've been toying with the idea), CD looks good but frontal area? That car is WIDE and not all that short.....