One of my favourite real-life cars - Vauxhall VX220

[Spiny Anteater]

Finally, I the random number generator has returned me to production cars And what a car, it's one I would seriously like to buy for my next car if circumstances permit, is s lightweight stripped-out little thing and looks fantastic. It is the Vauxhall VX220, very similar to the Elise but better looking in my opinion, a rarer sight and with a few more safety features (such as ABS). Plus I love the way you can hear the gears slotting into place about an inch behind your ear when you shift up or down

I'll be running it in A Class, which means I can do quite a bit to it, but not go overboard. So, for example, on the Speedway I can put in over 400bhp, but my self-imposed "anti-missile rule" of always going up at least one tyre compund per class means that I ran street tyres there. As a result, on the power tracks I ended up with slightly less than 400bhp as I had to lose some power to bring the PI back down after I added the spoilers. Still better than my first build though where I built (and tuned) it to 800PI, before I remembered that A Class goes up to 850

So, time to take on the Spirra. In the mean time, here it is taking in some rays at New York

[Spiny Anteater]

Power tune (gearing for Sunset Infield Short)

Upgrades:
Power: Race Intake, Exhaust, Cams & valves and Engine Block
          Street Ignition and Fuel System
          Stock Turbo and Intercooler
Platform: All race except stock weight reduction
Tyres: Firestone Street Tyres on Brabus Monoblock VI Multi rims, F=175/55R17, R=215/45R17
Aero: All forza parts

Stats:
Power: 388 bhp
Torque: 306 lb-ft
weight: 2046lbs

Tune:
Tyres: 29/29
FD: 3.30
1-6: 2.89, 2.15, 1.71, 1.40, 1.19, 1.02
Camber: -0.8/-0.8
Toe: 0/-0.2
Caster: 5.4
ARBs: 17.79/15.03
Springs: 366.2/525.3
Ride Height: 4.8/4.8
Rebound: 5.0/7.8
Bump: 2.7/3.7
Aero: 63/75 (50%)
Brakes: 48% front/100% pressure
Diff: 40/21

[Spiny Anteater]

Flowing tune - complete with gearing for Maple Valley Long

Upgrades:
Power: Race Cams & Valves
          Street Intake, Exhaust and Engine Block
          Stock everything else
Platform: All race except stock weight reduction
Tyres: Avon Slick Tyres on Racing Hart C4 rims, F=205/40R17, R=245/45R17
Aero: All forza parts

Stats:
Power: 294 bhp
Torque: 232 lb-ft
Weight: 2050lbs

Tune:
Tyres: 28/28
FD: 3.64
1-6: 2.89, 2.15, 1.73, 1.44, 1.22, 1.04
Camber: -0.8/-0.8
Toe: 0/-0.2
Caster: 5.6
ARBs: 21.39/17.03
Springs: 366.9/513.4
Ride Height: 4.8/4.8
Rebound: 5.0/7.5
Bump: 2.7/3.7
Aero: 125/150 (max)
Brakes: 51% front/100% pressure
Diff: 40/21

[Spiny Anteater]

Twisty tune - coming in the dim and distant future

[fndrbndr]

Power tune looked OK today.  It seemed to hold its own just fine with the GT400 cars. 

[Spiny Anteater]

It didn't do too bad, certainly the lap times were competitive with you and Bimmer but Open had half a second on my in his MR2. So I've had a bit or a rejig since then, with the results posted above.

The main difference between this tune and the one I raced is that the one last night had full downforce on it. I'd been trying to overcome turn-in oversteer but through turns it became understeer, especially if I was a little cavalier on the throttle, and the transition was quick and very difficult to predict. As a consequence, I had felt that I needed that downforce. But, by slightly raising my front bump setting and moving the brake bias forwards a touch I was able to make it more stable under braking, and softening the rear suspension a bit and stiffening both ARBs (but the front a bit less than the back) made the car more neutral in steady state cornering and the transition between the two became slower and easier to predict.

So, I tried reducing the downforce. That has helped a lot on Sunset Infield short, and also led to an improvement at Silverstone National. I haven't tried it at Sebring Short yet, but I believe it will be better than the car you saw. Sadly, on the power tracks it's not quite up there with the power built Spirra, although it is only about 0.3 seconds behind on each track. I'm crossing my fingers that it can beat the Spirra at one of the other types of track

[Snyder005]

Well, MR2's are very good A-class cars, prolly a few seconds slower then the Renault 5 on tracks.  I tried a grippy VX220 once, but I don't remember the times it ran, but I agree that it looks much better then the Elise 135R, though not the Exige, hahaha, my new favorite A-Class car!

Best of luck, this car will prolly be like lightning at grippy tracks!

[Spiny Anteater]

It's about the same as the Spirra on Maple Valley Short and Road Atlanta Short - just a few hundredths either way. But it really lost ground on Suzuka East - I would have expected it to gain most on that track with the extra top speeed and the longer straight, but it lost so much time in the last corner that it just couldn't make it up. Oddly enough it was about equal with the Spirra through the sweepers apart from that last corner so it may go better on the longer track. I'll certainly be giving it a run on the flowing tracks, although I suspect it will do best on Maple Valley long. I'd have liked to have run it last night, but it just fell a few bhp short of the magic 300.

There was also something a bit odd about the tuning on this. At first I was really struggling to keep the back end in line going into the first corner at Suzuka. Softening the suspension just made things worse. Lowering the rear rebound a little improved things a bit, but not enough to compensate for the worsening of the handling from the softer rear springs. Pushing the brake bias further forward improved stability some more. But the real major improvement came when I put some more stiffness back in the rear springs

And that seems odd to me, because it is completely counter to what I would have expected and to what I've seen on other cars. The best explanation I can think of is that the softer rear springs are not resisting the rise in the rear which is the corollary of the front end dive under braking. But as the springs are pretty stiff (even at the softest we're talking ~470lb/in on a 2000lb car) that seems a bit of a lame explanation. Can anyone do any better?

[Spiny Anteater]

As I said earlier, the VX220 seems to have something funny going on with the springs - as I softened them at the back it got harder to stop the snap oversteer. I ended up countering that with lower rear rebound settings, increased caster and a slightly forward biased braking setup.

As I predicted, it was faster than the Spirra around Maple Valley, but it is still about 0.3seconds behind the GT400 Miura (VX = 1:28.556). I'd like to put that down to the extra horsepower, but the Miura also pulls away a bit in the corners too while top speed of the two cars is within a couple of mph. However, the VX220 is now a good handling car provided you keep that maintenance throttle on through the corners (let off completely and it's a different story). I think it will make a better race car than hotlapper, just because you can be more consistent in it.