On the GTP account, I dug the NSX Gr.B out of storage and sent it to Sarthe. I need a new tune for it, but once it has that, it would be a candidate for an 8-lap race in the dry. It wasn't exactly dry - despite pitting 3 times, I needed to dwaddle on lap 6 to get the 6-lap win.
The 4-star Wheel of Despair wasn't impressed - it gave me yet another Mazda Atenza Sedan. As I already have 3 (one to keep stock, one to eventually fully tune with normal parts, one to eventually fully tune with potential "S" parts, specifically the carbon driveshaft and titanium pistons/rods), and it doesn't take a wide-body kit, I dumped it for 10,170 Cr.
On the Plus account, I continued my Gr.4 retest at Sarthe with the Chevrolet Corvette, forgetting I used it the other day. This time, the track was bone-dry. It has a nasty habit of power-on oversteer, weak brakes, marginal fuel economy (I went through 96% in the first 3 laps, and McEwen felt compelled to bring his Corvette down pit road 3 times in a dry race), and marginal tire wear (I was tempted to change them on my second stop on lap 5, and McEwen was tempted on his third stop on lap 6), but it will turn sub-4:19 laps in the dry, with a 4:19 flat on lap 7 on worn tires.
The no-cash 4-star Wheel of Despair gave a computer for the BMW safety car. Wow - a whole 630 Cr. if I fit it on an excess car before I sell it. Still, could be worse - it could have been the height-adjustable suspension I previously "won" for said safety car (worth a whopping 600 Cr. if fit to an excess car before selling) or a nitrous kit (which is worth exactly 0.00 Cr. when selling a car).
@Chris30, I haven't messed with Sarthe since PD messed with the clean race bonus a couple of physics changes ago, so I can't help you there. Pretty much any Gr.4 car can win at Sarthe. Do stay away from the BMW M4 - it is a turd pile stock. Some of the other low-PP Gr.4 cars really could use a dry track through the first 3 laps as they require a 1-stop strategy on normal difficulty. Even if you're playing on hard difficulty, the Lamborghini Huracan and Renault Megane Trophy are great choices among the Gr.4 cars that you can get at Brand Central - they're both quick and fuel efficient, though you'll need to adjust the fuel map on the Huracan to get 4 laps like Haywood does.