The locomotives were very similar technically to the earlier single cabbed 121 class locomotive. They were capable of 960 horsepower when delivered and 1100 horsepower following upgrades. The locomotives were originally capable of 90 miles per hour but EMD threatened to cut the warranty if CIÉ kept thrashing them on express trains. So they had EMD modify the overspeed governer to kick in at 75 m.p.h.
Remaining Class Members.Edit
Locomotive number 171 was last used in December 2013 as the Inchicore Works shunter. Locomotive numbers 141 & 142 are preserved in working order by the Railway Preservation Society of Ireland and 146 by the Downpatrick & Co Down Railway. No. 152 has been sold for parts but may be preserved and 175 has been bought by the RPSI for future restoration. Nos. 144,147,162,171,175 and 177 are stored in the Inchicore Works, 144, 171 and 175 are still in good condition. 162 and 177 are heavily stripped, 147 has no brakes.