Keep in mind that Amps has nothing to do with torque and power. Amp is just capacity. The little Kavan starter uses only a 1400mAh battery pack. Output voltage is what you are looking for.
Richard L.,
You're usually right on but I have to disagree with this statement. Try starting your car with a 12 volt lawn tractor battery. It's still the same voltage but won't likely have near enough cranking amps to turn the engine over.