Before I went to bed last night, I had a quick check on the Rollovers DPi's. There appeared to be what I think is a mistake or a typo in the ai.ini for all the cars (trail hint number).For those who will need this in the future...Simulating IMSA races I've got race terminating AI crashes and traffics at last corner of Long Beach so I've asked help here few pages ago and @KevinK2 suggested me to replace the Rollover prototype cars because their AI is not working well. So replaced the Rollovers DPIs by Rollovers GTP planet DPI and Rollover Oreca 07 LMP2 by Oreca tk and the issues are gone.
I remembered that a while back @Caddy_DPi uploaded a DPi physics swap for these cars, which I found in my archive. In it, he adjusted that number and perhaps changed the physics a bit, not to mention different sounds. I reinstalled that, and the cars and the ai worked much better. It looked like the original link is down, so I hope he doesn't mind if I share it. If he complains I will remove it:
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Today I was going the check the GTP DPi's later today but it looks like you already did- glad to hear they work better. You also mentioned a few other cars, but I did not have a problem with the VRC Formula NA 2021 and an Oreca IMSA that I had in my install, tested at 100% strength and 80% aggression.