Fastest and slowest action potential
You can search on Bionumbers.

Here is what I got after searching action potential:


Speed of action potential along non-myelinated invertebrate axons of ~10μm diameter = less than 1 m/s
Action potential speed in myelinated axon = 50 ... 100 m/s
Velocity of action potential in pyramidal tract at 37°C (in Cat Felis) = 164 m/s


It offers you references for every number.