BTCC Handling

I've been watching old Super Touring rules BTCC. Basically, mid nineties to 2000. I can't help noticing how well those things handle. I wonder why.

They are nose heavy front drivers, the tires really aren't that big, they aren't making much downforce and I don't remember tires from 1997 being ultra amazing. They seem to have factory unibodies and they aren't super light. In fact, aside from handling amazing, they don't seem that different from a modern Honda or Toyota.

Does anybody know what sort of torture they put the suspensions under or was it just super sticky slicks or some combination of those things?

BTCC is amazing, I don't know anything about the suspension set ups so I watch with interest.

My understanding of how to make a race car handle: Tons of negative camber, super-stiff springs, sticky tires, smooth race track that doesn't require much suspension travel, zero concern about ride quality on the street - since it's not a street car.

Yeah, I understand, but these things handled way better than modern BTCC cars. I mean, just eyeballing it, these things seemed to have near German Touring Car cornering speeds.

It may well be that the whole package simply works well and is easily understood and controlled by the driver. So technically not an outstanding handling car, just one very easy brought to the limits and held there.

Sorta like the old Porsche 911 vs 924 argument. The 911 is technically faster, but darn hard to drive fast. The 924 isn't as fast, but is a whole lot easier to drive fast. So, many times the lesser 924 bests the better 911.

Being only 2150 LBs helps the matters.

http://www.supertouringregister.com/document/8/

That goes through the Nissan Primera that ruled the late 90s.

The straight line speed is so far off from their modern counterparts that the relative corner speed is likely to seem far more impressive. Less time spent under braking and a slower rate of acceleration with effectively make anything appear to be a great momentum car.

Because the whole FWD and RWD arguments we've heard over and over again are overrated.

bmw88rider wrote: Being only 2150 LBs helps the matters. http://www.supertouringregister.com/document/8/ That goes through the Nissan Primera that ruled the late 90s.

Wow, so it seems like they had to stick with the "basic layout" of the factory suspensions. So like the Primera is a factory double a-arm front and twist beam rear setup and so was the race car. That said, it seems like the mounts were free and plenty of creativity allowed. Like mounting the lower control arms to the sump, for example.

It's also interesting that Nissan was so terrified of the twist beam but then it ended up performing better than the old strut.

alfadriver wrote: Because the whole FWD and RWD arguments we've heard over and over again are overrated.

Yeah, I'm mostly interested in the technical tricks. I have a nose heavy front driver sedan I'd like to make turn better. It already turns much better than most RWD cars I've driven, but nowhere near as well as the BTCC rigs did.

It seems the formula for making a heavy front-driver handle is as I described above. Make the suspension as stiff as you can bear and stuff as much tire under the fenders as possible, making them as sticky as possible.

One of the most incredible cars I've ever ridden in was a '03 VW GTI modified for D Street Prepared. Custom ground Control coil-overs, 18" x 285 section Hoosier A6's on the front, 18" x 245 on the rear. Beefy front and rear sway-bars. The whole set-up was designed by a VW enthusiast who also happened to be a suspension engineer and 3D modeled everything to the Nth degree. Oddly enough, the car was actually lifted a bit to improve the suspension geometry, which also helped clear the tires under compression since they stuck out past the fenders. The downside is the owner said the car was fairly brutal on the street, even when the R-comps were replaced with normal street tires (his previous ST class Star-Specs on OEM 17" wheels).

Those cars were really light @ 975 kilos. They had 50/50 weight distribution. The engines were lowered in the chassis and moved rearward to help accomplish that. One team (Vauxhall) even drilled out the axle shafts to save weight and then had to replace them frequently because they would twist. With the cage design they were using the shells would be supremely stiff in torsion. The only real deficit the front drivers gave up was that the front tires had to provide traction and steering. I used to turn almost identical times in my SpecMiata and ITB Volkswagen GTI and my GTI was nowhere near 50/50 weight distribution. I can see a BTCC car being very fast ,even with wrong wheel drive.

...and BTCC rules required RWD cars to run a higher weight. Ford ran the original Mondeos as RWD then switched to FWD later.

alfadriver wrote: Because the whole FWD and RWD arguments we've heard over and over again are overrated.

You bite your tongue! RWD is how cars are meant to be. FWD is just a sad compromise that people try to make work as well as they can and then make excuses for.

KyAllroad wrote:

alfadriver wrote: Because the whole FWD and RWD arguments we've heard over and over again are overrated.

You bite your tongue! RWD is how cars are meant to be. FWD is just a sad compromise that people try to make work as well as they can and then make excuses for.

Says the man who thinks the Audi Allroad is a decent used car

DaewooOfDeath wrote: They are nose heavy front drivers, the tires really aren't that big, they aren't making much downforce and I don't remember tires from 1997 being ultra amazing. They seem to have factory unibodies and they aren't super light. In fact, aside from handling amazing, they don't seem that different from a modern Honda or Toyota.

You're making a lot of wrong assumptions here.

I recently posted pics in another thread of Volvo and Ford super touring cars from the era. The Ford had a Mazda V6 (legal thanks to US market Ford Probe) turned around backwards and stuffed/canted so far down and back that the right side axleshaft went through between the engine's cylinder heads. Control arms and steering rack mounted to the engine because there wasn't room for "frame" members.

The Volvo's engine was so low that it looked like it was resting on the floor. Easily the engine was 6 inches lower than in a production car. Much further back as well.

I remember seeing a picture of an Audi touring car's fuel cell. There were three separate cells, and a bizarre and complicated layout of lines and pumps and pickups, for the goal of keeping the fuel mass as close to the center of the vehicle as possible.

Touring Cars resemble street cars the way NASCAR vehicles resemble street cars.

Yep they were developed by the same group of nuts that develop F1 and topline prototypes and similar.

I remember reading that the large diameter of the tires was not to cram wide rubber under the car, it was there only to clear massive brakes. They were relatively narrow compared to what they could have been.

You also noticed that when they came off of a curb, the stance of the unloaded wheels were exactly the same as when on the ground. Not much travel there!

Both 1995 Mondeos...

Stefan (Not Bruce) wrote: Yep they were developed by the same group of nuts that develop F1 and topline prototypes and similar.

Except Touring Cars were in many cases more expensive. A statistic I vaguely remember (saw it somewhere on ClubGTI, where there is a LOT of touring car info, not just VWAG either) that a top level BTCC campaign will spend an ORDER OF MAGNITUDE more on cylinder heads than F1, because they were required to start with "production castings". And lots and lots and lots of modification, and you may have to go through ten heads to get one where the core shift was favorable, and you may get the porting/modifications so paper thin in spots that they can only stand enough heat cycles to get through one race...

And then Nissan finds 10 more HP so you need to redo all of your R&D again to try to keep up!

I really like the TWR head from their S40 Volvo. It may have started out as a stock casting but the only thing left that is production-like is probably the decks, and the plane of the valve guides, and where the head bolts go. They milled off most of the head and started anew.

pinchvalve wrote: I remember reading that the large diameter of the tires was not to cram wide rubber under the car, it was there only to clear massive brakes. They were relatively narrow compared to what they could have been.

It's better than that. The rule said that no part of the bodywork may touch the ground if a tire were completely deflated.

Solution: Rubberband tires so you can get the car down low/sideskirts as low as possible for aero reasons.

The larger brakes were just a convenient bonus. "No action should have only one goal"

foxtrapper wrote: It may well be that the whole package simply works well and is easily understood and controlled by the driver. So technically not an outstanding handling car, just one very easy brought to the limits and held there. Sorta like the old Porsche 911 vs 924 argument. The 911 is technically faster, but darn hard to drive fast. The 924 isn't as fast, but is a whole lot easier to drive fast. So, many times the lesser 924 bests the better 911.

They were definitely comfortable on the edge. One of the best things about old BTCC is just how hard they are pushing at all times.

Knurled wrote:

DaewooOfDeath wrote: They are nose heavy front drivers, the tires really aren't that big, they aren't making much downforce and I don't remember tires from 1997 being ultra amazing. They seem to have factory unibodies and they aren't super light. In fact, aside from handling amazing, they don't seem that different from a modern Honda or Toyota.

You're making a lot of wrong assumptions here. I recently posted pics in another thread of Volvo and Ford super touring cars from the era. The Ford had a Mazda V6 (legal thanks to US market Ford Probe) turned around backwards and stuffed/canted so far down and back that the right side axleshaft went through between the engine's cylinder heads. Control arms and steering rack mounted to the engine because there wasn't room for "frame" members. The Volvo's engine was so low that it looked like it was resting on the floor. Easily the engine was 6 inches lower than in a production car. Much further back as well. I remember seeing a picture of an Audi touring car's fuel cell. There were three separate cells, and a bizarre and complicated layout of lines and pumps and pickups, for the goal of keeping the fuel mass as close to the center of the vehicle as possible. Touring Cars resemble street cars the way NASCAR vehicles resemble street cars.

Thanks for the info. Yeah, I was actually having kind of a hard time finding pictures of super touring built cars with the parts exposed. I had deduced that there were some crazy things going on under the carbon engine covers and behind the radiator ducting but it is hard to nail down exactly what they changed.

"Everything" seems to be the answer.

Sounds like a common side effect of cars built to a rule set. What has to stay, stays, and piles of $$$$ is thrown at the areas they can change.

So, like, you mean to tell me that building this "Mondeo Strut" was probably pricier than just making a dedicated suspension?

And this is how the Audis got so low.