As long as you don't touch the water you'll be fine. Salt water and FG's don't mix! Your dogbones will be rusty before the first tank's gone
Best time to race on sand is at low tide, and on the hard damp sand. The marder tyres just rip the beach to shreds, plus throw sand 50 yds and all over the croud that seems to gather.Absolutely brilliant! Take a shovel and make some bumps and ranps to make it interesting.
You will need to clean the car right down after though. Every metal nut and bolt need claeaning and oiling. If you leave it overnight it'll be a rusty hulk.
Ian F.