That starter relay just supplies 12 volts to the starter solenoid. The starter solenoid is what supplies the 12 volt 80 amps to the starter to turn the engine over. That is why there is always a heavy wire from the battery to the starter. The heavy wire supplies the power, but the starter solenoid has to be energised before it can provide the power to the starter.

I have hot wired car with just a thin wire from the starter solenoid to the battery.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
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Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD