[mustangII460]

I would advise using one. Even with a late model starter w/built on soleniod.

If your not using a starter switch that can handle alot of current The switch is going to burn up. Hopefulley your car doesn't burn up with it.

The solenoid is a big relay. A relay takes the load off of any switch.

All your heavy loaded circuts use a relay of sorts.

Relays will also keep the current from climbing into any harnesses etc that can result in fire.