There’s a new family of Delco Remy heavy duty alternators from Remy Inc. that are said to ensure adequate alternator output in spite of increased underhood operating temperatures.

The three new high-temperature alternators – the Delco Remy 28SI, 36SI and 40SI – are engineered and tested to work in underhood operating environments up to 125? C (257? F), Remy says. The new alternators are also well suited to any application experiencing extended operating temperatures above 110? C.

“Increased heat in the engine compartment is the dominant trend affecting alternator design,” says Remy vice president Kent Jones. “Our testing of 2007 engines shows that heavy-duty vehicles will consistently see underhood temperatures well above 110 degrees, with peaks up to 125 degrees.”

The Delco Remy 28SI heavy duty brush-type alternator delivers up to 180 amps of power at highway speed and 130 amps at idle. The model 36SI brushless alternator produces 160 amps at highway speed and 110 amps at idle. And the all-new 40SI is engineered to deliver 300 amps at road speed and over 200 amps at idle.

All three alternators feature new technologies, including a premium ‘Flex-Lead’ diode-bridge design and higher-capacity, press-fit diodes. Each is also available with ‘Remote Sense’ technology, which automatically adjusts output based on voltage at the battery terminals to help ensure an optimal state of charge.