Use the following trick to go over 1400 mph on test course. Make sure your GT-One race car has all the upgrades, the stage 4 turbo kit, super-soft tires, and a fresh oil change. Next, go into the vehicle settings for the car and make the following changes: Spring rate 4.0 Front/ 4.0 Rear, Ride Height 55 Front/ 55 Rear, Shock Bound/Rebound 1 Front/ 1 Rear, Camber/Toe Angles 0 Front/ 0 Rear, Brake Balance 9 Front/ 9 Rear, Limited-Slip Initial Torque 60, Limited-Slip Accel 60, Limited-Slip Decel 20, Downforce .45 Front/ 1.25 Rear, ASM 10, TCS 5. Here is the important part -- go to the Gear Ratio Settings screen and change the final gear to 5.499. Change the Auto Settings level to 47 and then to level 48. Do not change the settings for the individual gears (i.e., 1st through 6th) -- they should now be set to specific levels. Now, change the final gear back to 2.900, and do not forget to accept the changes. Go to the Max Speed Test. Make sure to do a 180 (turn completely around) to go the opposite direction around the track. Otherwise, you will be stopped and given your max speed at the other end of the track. As you go around the first and second corner, stay in third gear by holding R2 (if using an automatic transmission). As soon as you come off the second corner heading down the straight-a-away, release R2 after you reach a speed of 243 mph. The front end of the GT-One should lift up and you will start to go very fast. It is possible to set a max speed record of 1455 mph or better by changing the time at which you release R2.
Alternately, use the following settings with the Toyota GT-1 Race Car (TSO20) to get over 1250 mph on the max speed test. Use a manual transmission for best results. Spring rate Front- 0%, Rear- 0%,Ride height F- 0%, R- 0%, Shock bound F 7, R 7, Shock rebound F- 7, R- 7, Camber 0, Toe 0, Stabilizers 0%, Limited Slip initial torque F 0, R 5, Limited Slip Acceleration F 0, R 5, Limited Slip Deceleration F 0, R 5, Gears 1st- 2.572, 2nd- 1.613, 3rd- 1.125, 4th- 0.829, 5th- 0.646, 6th- 0.489, Final- 3.964, Downforce Front- 0%, Downforce- Rear- 100%, ASM 0, TCS 0.
You can attain a speed of over 5000 mph on the test course if you do the following. Set up the Toyota GT1 race car for the 1300 mph glitch in the game. Then, get a friend and set up the arcade mode for at least 15 laps and choose the test course. Have both players choose the GT1 race car which is set up for the top speed glitch. Have one person get on the bumper of the other person's car and start going around the test course drafting the entire way. You must make sure you keep drafting, because you will slowly start to carry more and more speed out of the corners until you reach a point where you can stay in sixth gear coming out of the corner. Once you have perfected this, the cars are able to attain over 5000 mph by this drafting method. Note: The game will sometimes lock up because it cannot handle the figures the cars start to put up.
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