General Discussion

[af1cummins]

I am trying to figure out what the specs are on a turbo. The engine is a 3406 and it's on a generator. There's a plate on the turbo that has       P/N 1674-1326  and AR.81 is stamped on it as well. I know that's not a lot of info for you guys to go on but it's about all I have. Any info is appreciated.

[Cat_Tech]

The part # is not a good part #, the AR.81 is the air ratio # of .81 is there a brand name on the turbo?

[af1cummins]

It says the turbo is a Caterpillar turbo.

[dave10010]

Post engine serial number.

[chrestenson6]

A/R is not the "air ratio". A/R is the ratio of the inside diameter of the scroll(snail shell) versus the diameter of the turbine outlet. It is used to match the sizing of the compressor and turbine housings to the gas or airflow requirements of the engine.

[chrestenson6]

p/n will either be a 7 digit  all numerical or a 6 digit with a letter in the prefix