Howard,
Re chassis set-up, the guys have pointed you in the right direction.
When on track, suggest driving off-line at the VERY least in the turns. When driving on line, you'll usually find the surface to be a bit more polished; move even a foot off line and the track is far more likely to be a wee bit rougher, offering a fair bit more grip. Another throttle return spring wouldn't be a bad idea either.
Looking forward to reading about the adventure!
Best,
T.