[/QUOTE]You can always tell when someone shows up with a silver can in their car. The 21.5 cars are quite a bit slower down the long straight than the silver can cars.[/QUOTE]

I can vouch for this. Swapped a 21.5 Hacker from my TC with about 40 degrees motor timing into my LWB M03 Mini and was getting pulled by a box stock M05 on a long straightaway. I had been running Silver Can in a TCS type format at my Summer home but had an extra Tekin ESC I used instead of the original Tamiya ESC. Decided I might as well put a BL in for racing in a mixed Mini class at my Winter home in AZ. By mixed I mean if it's small it's in the class so that includes 4WD Vaterras. The most recent race even had Spec Touring cars to help make up the class.

I got so frustrated I put a 17.5 in with boost and turbo. Got the speed but the Vaterra clobbered me and broke a rear upright.

Interestingly when I ran the 17.5 the first time I only had motor timing and really didn't see much speed difference between it and the 21.5. Different motor manufactures as well and I don't know how their KVs compare.

Think the Hacker is the better motor and since I now know the 21.5 is legal for TCS ,after coming back to this thread following a few months absence, I'm going back to the 21.5 and I'll work to get more speed out of it.