Multiple Hall Effect Sensors

I would start by looking at the timing or each parameter then seeing what type of load would be on the processor.

For instance:
If you wheel is 2 feet in diameter.
One wheel revolution is 2 Pi = 6.28 feet.
60 MPH ≈ 88 feet / second
A 1 revolution sensor would be approx 14 rev /second which is approx 71 ms.

Engine RPM:
5000 RPM ≈ one revolution every 12 ms (different if you monitor the points)

If you can make the wheel revolution sensor pulse long enough so the processor can deal with other one wheel before the other three pulse ends you should be able to collect the data.

The next issue is how to log and or display the data. And how to distinguish between going around a corner or having a low tire. Its not that hard but has to be done.

In general I don't see it being too difficult for an Arduino. I think the issues will be with the sensors (it always is) and automotive electrical noise.