[vetvetdoug]

Does an EMP affect vehicles or engines from the 1960’s?

[Kartographer]

My understanding is just cars with electronic ignitions

[RandallFlagg]

Nope.

[BigpapaBo]

Have a spare set of points and a condenser for the dizzy. A spare coil for the plugs also. This is why...
ANY length of wire not “protected” will charge up instantly to the induced voltage. A coil is a transformer (low voltage 12v to 40k-60k volts). That coil will charge up beyond it's intended use. Zap! It may melt the insulation or melt the thin wiring inside it. Either way it's gonna fry.
Have a spare alternator/generator with a regulator. Big windings inside those devices. Alternators usually have rectifiers located inside them. They don't do well with high induced voltages. Same with the generators and regulators.
I've switched on the AM dial every once in a while (In the ‘63 chev truck- updated engine to HEI). Static and noise in the background. I stepped on the go pedal and reved her up a bit. Noise increased.

Picture a metal device in a microwave at max setting. Not pretty. Now picture the microwave the size of the sky set at 1000%. Ugly

Newer vehicles may fair better due to the built-in protection needed for the HEI type ignition systems. But again anything else not tied into the ignition system may not make it. Fuel pump(motor windings)? Solenoids? Small sensors (Inlet air temp/flow) MAP/MAF.

The military folks know how important EMI protection is in aircraft and vehicles.
EA-6B’s and F-18G’s fly pods that can literally fry electronics as they fly over enemy airspace 10’s of miles away. (Blinding the enemy radar and comand-control systems)
HEMP is much bigger.

[TheThirdRuffian]

No, older vehicles are great for this reason.

I have a MOD Land Rover Defender (diesel) that is EMP proof, in part for this reason, but mainly tro trudg throught the snow and mud where I live.

An old VW bug would be my choice for a gas powered engine — plenty of parts, too.