Triumph TR4A

1965 to 1967
Overview
Manufacturer	Triumph Motor Company
Production	1965–1967
Body and chassis
Class	Sports car
Body style	2-door roadster
Layout	FR layout
Powertrain
Engine	2,138 cc (2.1 L) I4
Transmission	4-speed manual
Dimensions
Wheelbase	2,235 mm (88.0 in)
Length	3,962 mm (156.0 in)
Width	1,473 mm (58.0 in)
Height	1,207 mm (47.5 in)
Curb weight	1,016 kg (2,240 lb)
Chronology
Predecessor	Triumph TR4
Successor	Triumph TR5

The Triumph TR4A was built between 1965 and 1968 by the Triumph Motor Company in the United Kingdom.

The TR4A was an evolution of the TR4, updated with a new chassis. It was hoped the new, but more complex independent rear suspension would address the buying public's desire for more comfortable riding sports cars. This version has an "IRS" badge on the rear. It has been estimated that 75 percent of TR4A were built with IRS. In 1965 the TR4A IRS sold in the UK for approximately £968, with wire wheels and knock-on hubs being another £36, overdrive £51, heater £13 and seat belts £4 each; it sold for just under $2500 in the US.Engine: 2138 cc, 4-cylinder, 86 mm bore, 92 mm stroke, 9:1 compression ratio, 104 bhp (78 kW). The long stroke give this engine much of its torque. Standard inline-four engine

PERFORMANCE

• engine capacity 130.46 cu in, 2,138 cu cm
• fuel consumption 24.5 m/imp gal, 20.4 m/US gal, 11.5 1 x 100 km
• max speed 110 mph, 177.1 km/h
• max power (SAE): 105 hp at 4,750 rpm
• max torque (SAE): 85 1b ft, 11.7 kg m at 3,350 rpm
• max engine rpm: 5,500
• specific power: 49.1 hp/l
• power-weight ratio: 20.3 lb/hp, 9.2 kg/hp
• acceleration: standing 1/4 mile 17.9 sec, O—50 mph (O—80 km/h) 8.2 sec
• max speeds: 30 mph, 48.3 km/h in 1st gear; 50 mph, 80.5 km/h
• in 2nd gear; 75 mph, 120.7 km/h in 3rd gear; 110 mph, 177.1 km/h in 4th gear

In response to dealer requests, about 25 percent of TR4As were produced with a solid rear axle option (also called a live axle), similar to the earlier TR4. Also a under 2.0L spec engine for competition use aswell as competition suspension.  The TR4A was the first vehicle to offer an option for axle type.The new suspension eventually proved itself with the buying public and in racing, with three TR4A IRS models posting a team win and finishing 1st, 2nd and 3rd in class at the Sebring 12-hour race of 1966.

Competition engine (for under 2.0L class)

• engine capacity 121.49 cu in, 1,991 cu cm
• bore and stroke 3.27 x 3.62 in, 83 x 92 mm
• max power (SAE) 101 hp at 5,000 rpm
• max torque 118 1b ft, 16.3 kg m at 3,000 rpm
• 8.5 compression ratio, 50.7 hp/l
• specific power, max speed 103 mph, 165.8 km/h.

In 1968 the TR4A was replaced by the 6-cylinder TR5 (European model with fuel injection) and TR250 (US model with twin carburetors), both of which used the same body design.

Coachwork

Like the TR4, the TR4A was also available with the "Surrey Top" hard top system; a weather protection system with rigid rear section including the rear window and removable fabric section over the driver's and passenger's heads. This aesthetically foreshadowed the silhouette of Targa top cars.

 Film and TV

A Triumph TR4A in the Heartbeat, TV series