Ahh, outdoor racing. Be careful to not overgear outside with the 27t motors, even though it's very tempting with a bigger track. The cars ARE slow, and that's the point. The whole race is a lot more fun when everyone is pretty close to the same speed. If you need to, get everyone to gear the cars so that they are similar in speeds. It makes the racing entirely more enjoyable for everyone and it puts on a WAY better show for those watching.
Personally, I'd prefer to keep the rules the same for indoors AND outdoors, but some outdoor tracks just may dictate the need for a little more speed.
Is that Camaro on the left using vintage tires and wheels?