BMW 2002 turbo
170hp with 0.55bar boost from the single KKK turbo. Getrag 235/8 5-speed gearbox is standard with a ton of rear end gearing options from the motorsport division and a 40% lock ZF differential by default. Suspension is made of struts at the front and semi-trailing arms at the rear; an arrangement not not all that different from the E30 Group A car used some 20 years later. Stock springs are around 275 lb/in front and 250lb/in rear and make for some lively handling. Found that they offered a 'special lightweight package' which cut kerb weight to 1035kg with a full tank of fuel, so went ahead and optioned that on to ours. Uses the same Faretti Superbelt vintage tire from our Escort Mk1 and '66 Mustang. Matches up surprisingly well with the Mustang despite the 100hp deficit. This car was really genesis for the idea of the light, nimble, turbocharged touring car and it’s really cool to see how that comes across in our systems.
BMW 320TC
We had a good starting point in the M3 GT4 and some very detailed technical manuals/setup sheets covering the differences needed to make it a WTCC car. The rules for both series require that the race car stays very close to the road car as far as bodyshell, suspension design, and aerodynamics. Fun fact: this is probably the only car we have where zero rear wing actually equals zero rear downforce. Plots in the manual show it goes from 100% front to 80% rear aero balance with increasing wing angle. (top tip: there is really no reason to run it lower than 4.0 in the setup. Real teams use a high angle even at Monza) It’s a lively car to drive. During research, I found it a little amusing to see that every other game with this or other WTCC cars has used only the FIA maximum rev limit of 8500rpm to design their engines. These really make max power around 6000rpm and you'll want to shift between 6200-6400rpm. A regulation limit of 2.5bar boost on a tiny 33mm intake restrictor means these engines are struggling for air at rpm any higher than that. That 8500rpm limiter exists, but it really is never used as the other rules around the engine are more strict. Still, it pulls *strong* for a little 1.6L unit and always feels like it has plenty of power. May have 100hp less than the M3 GT4, but it also weighs over 300kg less, has narrower, harder rubber and no TC or ABS. Can be a challenge getting the thing slowed down and out of a corner as fast as possible. Tons of fun racing in tight packs.
Ford Mustang 2+2 fastback
The Mustang was a huge hit from day one, and with models like this it’s not difficult to see why. We’ve opted for the K Code engine with 271hp, 3.0:1 rear end ratio by default as it's best for most track use, 135 lb/in rear leaf spring from the handling package, and stiffer than stock front coils as the standard 100 lb/in guys just can't handle in hard track use especially in AI hands (but they are available in setup if you want to try the car as it came out of showrooms). Lots of other little bits were able to be taken and modified from the Escort Mk1 with minor edits as the architecture is essentially similar between the two cars. Aerodynamics are not good, suspension is rough around the edges, tires are nowhere near modern standards, and that engine is well beyond all of the above, but man...Is the slowest car in game also the most fun to race? I think maybe so.
Ford Mustang GT (2015)
Independent rear suspension in a Mustang! Feels almost sacrilegious but you can’t really argue with the result. Chris Harris put out a video on the car recently and said something along the lines of ‘they’ve taken a very sophisticated car and tuned it to act like a hooligan’. I think that is about as spot on as you can get.
The nice thing about Mustangs is that hotrodders tear them apart the instant they get the chance. Means good data and numbers are already out on the interwebz that were useful to fill the gaps here. Stock springs and dampers show a significant rear bias, leading to oversteer and drifty behavior as the dominant characteristic. It feels, to me, like they have gone to some length to tune the new rear suspension so that it still has some of the feeling of the old generation’s solid rear axle. ‘Pushy-Loose’ is a term you might use for it. Not an altogether bad idea, but it does leave you feeling that some performance might be left on the table for the sake of fun dynamics. I guess that’s a choice we can stand behind, right? Plenty of room for a car to be designed for fun rather than getting that last 1s at the Nurburgring.
Decided to not use the optional 3.73 rear end in the default setup as it is useless on track. Makes 2nd gear too short to use on most tracks and you run out of 5th too early while 6th is too long for anything but highway cruising no matter what. The standard 3.55 is much better for track use if you then treat it like 6th gear doesn’t exist (Or 2nd for that matter. Run 3rd through 5th for best lap times and use the excellent torque curve to make up the difference).
Fun drive and faster overall than expected. Just heavy...
Ruf CTR ‘Yellowbird’
Engine and gearbox are all good to Ruf specs. Published power and torque numbers smell funny on this one; I think it really made a lot more than the 470hp they claim and definitely made a lot more than 408lb-ft in torque. Aero model has been roughly matched to data available for the Porsche 930 with a whale tail. Suspension is strut front and semi-trailing arm rear with spring rates I quickly found other people using on 930 Porsches. Didn't spend much time tuning it as we've got an expert amongst us in Doug, but it's already good fun.
Set it to use our Masculin tire set and it matches up quite well with the modern cars when running on those. Also added a 'CTR Denloc D40' tire to copy period-correct Dunlop Denloc D40s that originally came with the car and were used for the famous 8:05 Nurburgring lap; go watch the Fascination video on Youtube if you haven’t already. Bit of a handful, but I expect a lot of you here will like that.
Doug: Interestingly, I actually drove one of these cars (pretty sure it was a real one) at Watkins Glen back in the early 90's. It belonged to a well-off club member who was looking for an opinion on his driving.. The thing i remember most about it was not being able to get the throttle all the way down on the straights until just before the the braking area for the next corner. Saying it's handfull is an understatement.
We were talking more like 600 hp at the time in conversations. I thought it had adjustable boost, but that might have been added by the shop that was supporting this car.
Set physics to all the info i have from the years setting these types of cars up. Changed the brake power and bias, moved the weight bias back to 40/60, Adjusted the motion ratios to some direct measurements i've used setting up 911/930's. Casey’s spring rate and damper values were almost spot on. Some slight tweaks needed there. Added proper sized swaybars. It all works pretty well. Get your trailing throttle heads screwed on for this one
This is one epic car. If you’re on the fence about this DLC, IMO this is the car that should push you over.
Ruf Rt12 R
We could 'steal' a lot from the RGT-8 for suspension and basics. Aero package is more or less a mildly-tamed Cup car, so scaled down the aero package for a GT3 Cup we made many moons ago and used that. Good for around 400lb downforce at 150mph. Weird gearing on this one. Huge spacing in the first three and 3rd gear takes you all the way to 120mph, then 4th-6th are very evenly spaced up to top speed of 370kmh. For most tracks, that means you just put it in 3rd gear and leave it there for a long time; let massive mountains of torque handle the rest. It works out well, but it’s a slightly unusual technique for most drivers. AWD is an option on this car, and we opted to use it. The rear engine weight bias means not too much it sent to the front, but it’s enough to make a difference pulling out of corner exits, which it does in a strong way. Used our Audi R8 V10 plus method for sending roughly 15% of engine power to the front wheels. Really fun car. Very quick!