I recreated the Vette you created for me in DCR1. Not exactly the same, but pretty close. The only problem is that it drives like junk. It bottoms out a lot. I think it might be a weight factor. I had to max the hardness just to keep it from always bottoming out. It will at least hold its own weight standing still. I was thinking some angle locks might help lighten the load, but haven't played with them yet. Although, I think it might need far too many angle locks attached to other angle locks, which we can't do.
I played with tire pressure and max compression too. It didn't help much. Can you play with it and see if you can get it any better?
I was able to complete "Lost" with it only if it was in boost mode at the time of the secret jump. Without boost, it can't maintain enough grip on the curve to make the landing platform. Again, I think that is a weight issue.