Which Pinion do I need ?

I see a few different pinions for 5mm shaft...which one do I need for my gorillamax revo? I have a MGM 160 and Neu1515/1y (2200Kv) with 4s lipo so how many teeth do I start with? (using stock revo diffs) Should I buy a range of 3 or 4 pinions?

[skellyo]

We'd need to know what spur gear you're running also.

I have a 65 and a 72 spur.... got both was not sure which I would need ...this is my first real powerful brushless system...hey also do you need to use metal spurs to survive the power or can you use plastic also?..

[skellyo]

Use plastic only when possible. However, you really should look into a Strobe spur for that beast.

I wonder if gorillamaxx will incorporate the new e-maxx revo style tranny in place of the older style they are using now then the strobe may not be be needed.