[Star Sage]

So in Shadowrun 4th Edition Anniversary they mention how vehicle acceleration comes in a 'walking' and 'running' movement rate. Particularly at the top of page 168 they mention that the driver can make a vehicle test and have each net hit add 5 to the vehicle's movement rating.

So what I am wondering is 1) Do these speed boosts stay until you purposefully slow down? And 2) Does making this vehicle test to speed up take up any actions similar to how sprinting does?

[Shaidar]

Yes on both counts.

My table applies the Newton/Murphy Theorem to the first.

Unless acted upon by an outside force
So you retain any and all increases to your current speed unless your vehicle is shot by a sufficiently large impact (AV munitions or Assualt Cannon) or rammed by another vehicle.

Vehicle Damage
Whenever a vehicle is hit by an attack, it resists damage as normal, rolling Body + Armor. If the attack’s modified DV does not exceed the vehicle’s modified Armor, no damage is applied. Note that since many vehicles will have large Body dice pools, gamemasters are encouraged to use the trade-in-dice-for-hits rule (4 dice equals 1 hit) to simplify tests. Your average tank, for example, will automatically get 4 hits on a Body Test by trade in, so there is no point in rolling unless the hits needed are higher than 4.

Crashing
Just like Knockdown, if a vehicle takes more damage from a single attack than it has Body, then the driver must make an immediate Vehicle skill + Reaction (3) Test to avoid crashing.
A vehicle that has crashed is out of Chase Combat

So any single attack large enough to induce a Crash Test that is successful (ie: not a crash) reduces the vehicle to its Speed Rating in order to maintain control.

OR

When what can go wrong does go wrong
Until the failure of any Vehicle Test not described above

Vehicle Tests
Characters don’t need to make a vehicle test every time they operate a vehicle. For normal everyday tasks, like driving to the Stuffer Shack, it’s assumed the character performs this automatically. A vehicle test is called for only when there’s a chance of bad consequences (like crashing), or if time is a crucial factor (like jumpstarting a car while under fire).
To make a vehicle test, the character rolls Reaction + the appropriate vehicle skill +/– the vehicle’s Handling. The threshold depends on the difficulty of the task being performed—see the Vehicle Test Threshold Table. A simple task (avoiding a large boulder in the middle of open terrain) may only have a threshold of 1 hit, while a more difficult task (making a hairpin turn to dive into a narrow opening) may require as many as 3 or 4 hits.
Depending on the circumstances, failure to achieve threshold doesn’t necessarily mean that the vehicle crashes—it just means the driver failed to perform the maneuver he intended. Unless the purpose of the vehicle test was to avoid crashing, the driver manages to pull away in time and can make another attempt.

We ruled that if your test was similar to attempting to take a corner at faster than safe speed missing the Threshold by 1 would entail completing the turn at a safer/lower speed, so coming out of the turn or maneuver your vehicle would be traveling no faster than its rated Speed.


Evidence for your second question

Complex Actions
Fire a Vehicle Weapon: A driver or passenger may fire a vehicle weapon.
Make Vehicle Test: A driver spends a Complex Action when executing a maneuver that requires a Vehicle Test. (It doesn’t cost an action if the driver is making a Vehicle Test to avoid a crash.)
Ram: The driver may attempt to ram another vehicle (see Ramming, below).

Any Vehicle Test which is not to avoid a Crash takes a Complex Action to perform.

[Star Sage]

Thanks for the timely answer, though this does make me wonder a couple things 1) Does this mean a drone needs to use one of its initiative passes every turn in order to not Crash? 2) Does this mean a driver can't fire a vehicle mounted weapon without having more than one initiative pass?

[Shaidar]

Again, yes on both counts.