I race in the Flying Miata Series here on GT Planet and we use this car on sport softs. Tuning is prohibited, but I do have around a few thousand laps using this car and two weeks ago the series did SPA.
I have not tuned this car, but here are the shortfalls that I saw in the stock tune when racing at SPA. The car has bad understeer in some key areas. That needs to be corrected. I also experienced outside wheel spin coming off of some of the 2nd gear corners. An LSD adjustment is needed there.
Things I would consider to improve this car.
Add the adjustable LSD first. It comes with settings of 10/40/20. I would be more happy with 10/20/5 to start with. With my experience spending alot of time with the other Miatas in the game, fine tune should put Initial Torque somewhere between 10 and 15 and LSD Accel somewhere between 15 and 20. Just put some sport hard tires on it and see which rear wheel spins first coming off a slow corner. Inside wheel spins, lower LSD Accel. Outside wheel spins, raise LSD Accel. Both wheels spin at the exact sme time equals perfect.
Next, I would try these things to reduce the oversteer. Do some testing, one change at a time. Or if you're in a hurry, slap all of these suggestions on and see where you'll end up. I have spent lots of time with Miatas in GT5 so I'm pretty confident this car will also respond will to the below changes.
- Increase front downforce to max of 20
- Reduce rear downforce to somewhere between 25 and 35
- Add some camber, the car needs it. On sport med/softs, I would be around 2.0 to 2.5 front and 1.8 to 2.2 rear. I like camber so I'd start 2.5 front and 2.0 rear.
- Anti-roll bars need to be higher than 1/1. I would look for 4/2 to start with. For less understeer/more oversteer raise the rear to 3 or lower the front to 3.
- Front toe to somewhere between -0.10 and -0.20
- Rear toe to somewhere between +0.05 and +0.20 (the stock setting may be o.k.)
- Spring rate could increase. I would put this car on sport tires closer to 10.0 front and 8.5 rear. For less understeer/more over steer, I would increase the rear.
- Dampers need to be set relative to springs, so if I was at 10.0/8.5 on springs, my dampers would be set 7 ext/5 comp front and 6 ext/4 comp rear. if you change spring rates for more/less understeer, dampers may need to change with them?
- Brake balance is pretty close on the Miata. I ran 8/10 in the series at SPA. You can get away with anything along the scale with a two number split 4/6, 6/8, 8/10. Test with your controller and style. I went to Top Gear test track and just did some stopping tests. 8/10 didn't turn the front tires red for me and provided the shortest stopping distance.
- Gear ratios. I would lower the 2nd and 3rd gear numbers a bit, just to even out the spacing between all five gears. Then play with final gear to get the car to top out at the end of the longest straight. We could not top out the car at SPA with tuning prohibited. 4th gear was a bit sluggish, which is why I would lower 2nd and 3rd, giving you more time in each of those gears.
Hope this helps. Sorry that I haven't tuned this car yet, but hopefully providing you with what I would do to the car to make it faster is helpful. Feel free to visit my garage link below for more detail on fine tuning.
Keith
