GM BLACK 140 AMP 1 OR 3 WIRE

Internal Regulator, Single V Groove Pulley

Part Number: AF4270-1140

Important Information: In order for an alternator to charge properly, an alternator must be grounded to the engine block. If an alternator has paint or clear coat on the mounting surfaces, it may not be grounded and will not charge. Many mounting brackets are also powder coated, clear coated, painted, or plated. The alternator will not ground properly without a ground wire from the alternator housing to the engine block. (This wire should match charge wire size).
A fully charged battery is at least 12.6V, not 12.0V. A weak/defective battery will cause premature failure. Never disconnect the battery with engine running! This causes voltage spikes that will damage the alternator.
Aeroflow Performance alternators spin at approximately 2.5 times that of crankshaft RPM, so an engine at a 700 RPM idle would spin the alternator at 1,750 RPM. The maximum RPM of this alternator should not exceed 15,000 RPM which typically allows for a maximum of 6000 engine rpm. For engines that turn past 6000rpm it is recommended to check pulley sizes carefully to ensure the alternator stays under the 15000rpm maximum at all times. The alternator pulley supplied is 1.75" / 44.45mm diameter. The internal bearings and components are not designed for extremely high RPM's. We strongly recommend that you calculate your pulley ratio to determine if your alternator will operate within the safe RPM range.