On 9/15/2011 4:54 PM, Hatfield wrote:

For example: Sony Shortwave CDX-GT570S

I would be curious for anybody's experience about how much
interference a running motor makes to this radio's SW reception while
traveling down the road?

Basically, what you ask is dependent on the individual -vehicle-.
Depends on how well shielded the ignition system is, what the numerous
computers and data buses are radiating and how quiet the fuel pump is.

I've even seen a case where, if the car next to you was listening to a
certain commercial FM broadcast station, its receiver oscillator would
interfere with a specific two meter ham repeater you were listening to
in your car.