[Jake Raby]

I have not tried a 3" pulley. My hypothesis is it would be great on the track, but would suffer greatly in highway scenarios. I say this because 4" seems to be on the ragged edge.
Have fun.

Send it to me and I'll dyno it back to back and test some other dynamics of it and how they impact the engine, too.

Just like bigger is seldom better with an engine displacement and "just right" is the hardest sweet spot to find, there becomes a point where smaller is not better with something like these pulleys.