[Nonfractal]

I am a bit stuck on this line...

lighter cars can run longer mm/rev gears and still accelerate like a kicked cat.

 What is a longer mm/rev gears?

Also toothpaste stopped being abrasive some years back so would suggest a mildly abrasive kitchen cleaner.

Also also did you mention the cigarette lighter trick?

Regards
John

"Longer mm/rev " AKA "taller" gearing means that the car will travel further for one turn of the motor, leading to higher top speed.
Longer gears can deaden the car's acceleration and braking, especially if the car is heavy.

Many abrasive products can be made to work. 

I don't advocate the cig lighter trick because it:
 - risks damage to motor pods, chassis, nylon pinions etc.
 - does not work for alloy crowns.

Jeremy, 
I have something on selecting the right gears to fit 
I'll post it later.


Alan