I'm fairly confident in this one now to post the specs I have decided on. Car feels good but will bite you without TCS so you have to learn it's limits, but once you have it down it's quite fun. I went with little aero on this one for a couple reasons: 1) the recently shown Z racecar that will compete in the Fuji 24 hour race has no additional aero over stock besides the rear wing, and 2) GT4 cars tend to have very little additional aero over stock besides a rear wing and/or diffuser. I thought just the wing was appropriate here, adding a diffuser would have been too much downforce in the rear. The car as shown below is fairly neutral. I was aiming to match real life GT4 times at Spa and even at these specs it is 1.5 seconds quicker than the pole time for the recent Spa 12HR. Oh well.
For the gear ratios, you have to set the Top Speed to 800 km/h (Max), then put 1st and 2nd gear all the way to the left. Set 4-6, then return to 1-2 and set them, then set final drive. 7-9 can be set super high so you can ignore them as they are not needed. When I build cars like this I like to use real settings where appropriate, so with this car I used the stock 3.538 final drive ratio from the 6MT (9AT is 3.133) and then used available gearing from the Quaife QBE69G 6-Speed HD sequential transmission. The only thing "custom" is 5th gear, as I felt that everything Quaife had available was too tall or too short.
High RPM turbo is used to keep wheel spin under control at low revs.
Wide body probably optional.
Only aero added is the small rear wing.
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(Ignore the name of the tuning sheet at the top)
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