[RMS11]

Having driven against 1771 in 4 matches, with them in about 8, and watched quite a few others, usually their fans seem to help much more with maneuverability rather than pinning. They can make turns much quicker, but in this game pinning is really about positioning. You much kinda wedge your close to their trailer hitch and push at an angle. Other pins usually are fairly easily escapable, fans or no fans. Note the last qualification match of Palmetto, 21 shut down and pinned 1771 and their fans the hole match.
So in conclusion, I have seen fans effective to aid in turning and some acceleration, but dont make a huge difference in terms of pushing and pinning.