So I used this an an excellent starting point. I highly suggest everyone do the same. Start with his tuning and then do a race and then come back and read my settings.
Before I list what I did, I want to talk about the car a little bit. It's a very powerful car. It's unwieldy powerful and that's why this post is necessary. We're all having issues controlling this beast. You have to tune it to your liking, when you get the car stock it's boring and can't really compete. When you start making performance upgrades, you can get top speeds of 298MPH, but you'll never get there if you don't make the adequate changes to your mechanics.
So an important thing to note is that this is a masterful car. Due to it's high power and torque, you need to drive it like a race car. Half the problem I noticed was that even with my preferred settings, I was over-driving the car like a madman. This car really requires throttle control. If you over accelerate you're going to eat ****. You need to learn to control the throttle better. Coming out of a turn, don't go balls to the wall on the gas while you're still turning a tight corner, you're just going to spill your guts on the track. You still need to take corners like you would a regular car. (you're going faster than you think) The other thing is to maintain throttle control on straights. If the car starts bumping, jumping or jerking you need to control that with strategic throttle bursts. If you don't learn these, you're just going to launch yourselves into every wall like a jackass.
Braking is another important aspect of this car. This car, like all other Gran Touring models, requires proper braking. If you try and brake wrong, you are not going to be very successful racing this car. First lesson is the basic lesson, brake straight. So with slower cars or heavy cars you can get away with braking in corners, you will not be able to do that with this car. It takes a long time to get used to, I never realized how much I was actually braking in corners. This is part of over-driving a car. We get excited, want to pass someone or want to increase time distance so we try and fly up to the corner and end up braking in it causing all sorts of handling problems from over to under steering. The solution to this, is braking in a straight line. If you brake in a straight line, you will be able to turn more effectively. (Remember this rule: Slow in - Fast Out. That's an actual Circuit racing saying) This car will also at times require the use of your Handbrake. Use this sparingly because this car is prone to sliding right through the turn and spinning out. Just tap it a little in the turns if you need the braking boost.
So regular brakes, straights and brake early.
Handbrake, limited use, only use in turns and just tap it a little for that edge.
If you don't follow this advice and just start messing with the settings, no matter what you do on what part of the track, straights, turns, braking, accelerating, you're just going to end up doing donuts in the middle of the track like a NASCAR driver in victory lane... only you'll be in last place so you'll just look silly.
Now I'm a gritty style racer, so you may not like my settings. I took out some of the oversteer from his settings, so you HAVE to make sure you maintain a soft racing touch. Otherwise these are pointless.
This is what I'm currently using, it's not perfect, but I've won a few 1st's with these:
Top to Bottom:
Tires: Sport-Hard/Sport-Soft
Suspension:
Ride Height: 70in/71in
Spring Rate: 5.09/11.00
Dampers (Comp): 4/8
Dampers (Ext): 5/7
Anti-Roll: 5/6
Camber: 0.0/0.0
Toe: 0.0/0.21
Brake Balance: 6/5
Drivetrain (Trans)
Max Speed: I set this to 100% (There's that gritty racing setting) Adjust lower for tracks with more turns.
Drivetrain:
Initial Torque: 28
Acceleration: 25
Braking Sensitive: 20
Twin-plate clutch
Power:
Engine Tuning: Stage 3
Sports CPU
Racing Exhaust
Isometric Manifold
Sports Cat Converter
Intake Tuning
(I don't use a supercharger, it puts me over the PP of most races)
Body:
Downforce: 215
Ballast Weight: 0
Ballast Pos: 0%
Weight Reduction 1 (once again, didn't go with 3 because of PP limitations)
Carbon hood and window reduction.