Around the same time of the Class 142 development, a Pacer railbus was being developed by Kilmarnock based Hunslet-Barclay.
The units used a Walter Alexander bus body.
The units were given the number Class 143 and entered service in 1985.
Again with two 205 bhp engines giving a total output of 410 bhp (310 kW) and a top speed of 75 mph (121 km/h), the class originally had a capacity of 122 passengers.
The class was used in the North East before being transferred to Wales and the South West, and were moved over to Valley Lines and Wales & West control during privatisation.
They then passed on to Arriva Trains Wales,  Wessex Trains, First Great Western and Transport for Wales.
The interiors were completely changed in 2000, when the Valley Lines service was introduced, with full back, coach-type seating installed throughout, along with improved fittings.
This reduced seating capacity to 106 seats per set.

Then came a similar Class 144 unit, a Walter Alexander body on BREL underframe, which was introduced in 1987.
A unit was formed of either a two-car set with 122 seats or a three-car set with a total capacity of 195 passengers and 690 bhp (510 kW), though still limited to 75 mph (121 km/h).
The units were used in the North East, passing to Northern Spirit at privatisation, then to Arriva Trains Northern, Northern Rail, Arriva Rail North and now Northern Trains.
Around the same time of the Class 142 development, a Pacer railbus was being developed by Kilmarnock based Hunslet-Barclay. The units used a Walter Alexander bus body. The units were given the number Class 143 and entered service in 1985. Again with two 205 bhp engines giving a total output of 410 bhp (310 kW) and a top speed of 75 mph (121 km/h), the class originally had a capacity of 122 passengers. The class was used in the North East before being transferred to Wales and the South West, and were moved over to Valley Lines and Wales & West control during privatisation. They then passed on to Arriva Trains Wales,  Wessex Trains, First Great Western and Transport for Wales. The interiors were completely changed in 2000, when the Valley Lines service was introduced, with full back, coach-type seating installed throughout, along with improved fittings. This reduced seating capacity to 106 seats per set.
Then came a similar Class 144 unit, a Walter Alexander body on BREL underframe, which was introduced in 1987. A unit was formed of either a two-car set with 122 seats or a three-car set with a total capacity of 195 passengers and 690 bhp (510 kW), though still limited to 75 mph (121 km/h). The units were used in the North East, passing to Northern Spirit at privatisation, then to Arriva Trains Northern, Northern Rail, Arriva Rail North and now Northern Trains.
Pacer (British Rail)