I am doing a mast service in ny state. I decided to try using aluminum wire, never used the. Cable called triplex. I thought your not able to undersized a neutral in long island residential, but could be wrong. Can I get a little help. Anyone know the foot pounds I need to torque this aluminum wire at in the meter?

Are you doing a mast service on an outbuilding? Or the main service?

The utility usually provides the aerial cable.

We have a resident expert here that lives in NY, perhaps he can help with the NY question, other than that I would suggest you check with the local inspector.

Reduced neutral is allowed by Code when the calculations are performed for interior feeders. Service entrances laterals, esp by the utility, is done often without calc done.

Torque values are given on the labels of equipment, for the mechanical connectors, or lugs. Not by the wire. Need to look up the specs of the meter trim/socket you will be using.