The car’s specification is extensive, so why not make yourself a cuppa and set aside half-a-n-hour to read through it?
It comprises, in brief
• Engine
The FIA-homologated ‘87mm’ 2,188cc engine is fitted with forged pistons, lightened and balanced conrods, a nitrided and balanced crankshaft, a works-specification rally camshaft and followers, and a late 511695 type heavily reworked cast steel cylinder head complete with homologation-sized inlet and exhaust valves, double springs, mechanical rockers and hardened shaft.
The cylinder block is internally prepared to works-spec with widened oil passages, nodular cast liners, uprated bolts throughout, and a crankshaft-mounted harmonic damper.
The distributer has been rebuilt and recalibrated by specialist Martin Jay of Distributer Doctor. A high speed starter motor and oil breather/catch tank are fitted.
• Carburation and fueling
The mechanical fuel pump has been removed from the block and the aperture blanked off. Fuel is now supplied with twin electric pumps and pressure regulators that have been neatly located under the fuel tank.
The petrol comes from a boot-mounted, aluminium 60-litre foam-filled fuel tank. The internally run fuel lines are as per the works TR4s and the fuel lines in the engine bay are braided.
Twin period-original Italian Weber 45DCOE carburettors sit on period SAH inlet manifolds, with the correct linkage and air filtration.
• Exhaust and manifold
The TR4 exhales through a Revington TR stainless-steel, spring-jointed 2¼-inch rally exhaust system fitted to strengthened mountings throughout and its twin boxes custom are located high in the chassis. It connects to the engine via a stainless-steel, high-flow competition manifold.
It is, as you’ve probably already guessed, fully compliant with modern road rally regulations and trackday noise limits.
• Cooling
Cooling is taken care of via an uprated five-core radiator and pressurized overflow tank that is ducted into the front of the car with a custom aluminium shroud to replace the standard cardboard type.
The car is also fitted with a vertically mounted 13-row oil cooler fed from the oil filter housing.
• Gearbox
The gearbox is a competition works-spec OE Triumph gearbox fitted with an uprated layshaft and bearings, steel bushes throughout, works ratios and uprated bearings.
It also has an uprated high-pressure, Laycock A-type overdrive modified with uprated clutches, accumulator pump, bearings, and linings. Overdrive on all forward gears is selected via a stalk on the steering column.
The whole lot is mated to a heavy duty competition clutch and uprated propshaft with larger UJ’s fitted front and back.
• Rear Axle and Differential
The rear axle is to works specification and fitted with a limited slip differential and competition 4.33:1 final drive ratio as per the FIA Homologation, and uprated Timkin bearings and seals. Standard pattern driveshafts and six-bolt hubs complete the specification.
• Brakes
The front brakes are solid discs and late calipers as per the FIA Homologation and UK MSA regulations. They are fitted with Mintex M1144 pads and piped through a balanced dual-circuit that separates the front and rear hydraulic circuits.
The rear brakes are nine-inch homologation-spec aluminium finned drums fitted with Mintex M20 linings, an uprated shoe hold-down kit and OE Girling cylinders.
The handbrake is a tunnel-mounted, works-spec cable arrangement using a Revington TR kit. It is MSA-legal for road events.
• Suspension
The front suspension comprises late TR4 negative camber uprights fitted with large stub axles. The hubs are aluminium and to works-spec including larger Timkin bearings.
Koni adjustable shocks and uprated coil springs are as per works spec, and adjustable top mounts enable adjustment of both camber and castor.
The standard production wishbones have been assembled with polybushes and stainless-steel inserts, and an RTR front anti-roll bar and mounting kit has been fitted.
The car’s rear suspension is similarly impressive, comprising 175lb rally-spec leaf springs fitted with eyebush turnover coils around the shackles as per the works cars.
Polybushes and solid bushings are fitted to reinforced pick-up points, and the car is also fitted with the very rare twin-valve DAS 9 Armstrong lever-arm dampers and strengthened drop links mounted to works-pattern reinforced rear turrets.
• Chassis
The chassis has been strengthened to 1963 works specification after consultating with the original Triumph Competitions Department mechanics. As such, it benefits from comprehensive strengthening to key areas including the front and rear suspension wishbone and damper mounts, the front and rear turrets, the engine cross member fillets, and the gearbox mounting plates.
There is also additional cross-tube and spring hanger reinforcement. The chassis leg has been chamfered to accommodate a 2¼-inch exhaust system.
Many of these modifications were carried through into the ultimate specification for the four Triumph team cars for their last international event in 1964 and survive on the four factory-built cars today.
• Wiring & Electrical
The car is fitted with a specialist Revington TR replacement wiring loom which is a close copy of the loom in car number ‘6VC’ but manufactured in modern material and fitted with modern connectors to allow fitment of an engine bay fuse and relay panel.
The dynamo has been replaced with a high output OE DENSO alternator mounted on a custom-made bracket set, with the appropriate wiring loom changes fed into the loom design. A spare coil is mounted in the engine bay, ready to take over if needed.
The car is also fitted with a pair of period Italian FIAMM twin airhorns.
• Underside
The underside of the car is protected by a 1963 ST customer-spec removable sump guard with an additional aluminium ‘Liege’ plate which protects the engine, gearbox, exhaust system and propshaft from damage.
The car is fully undersealed, and this was reapplied in 2019.
The owner has driven one of the original factory TR4s and says that this one drives just as well. He goes on to say that it is “light and powerful”, “sweet-handling and well behaved” and “displays that happy balanced handling that takes a while to find”.
We’ve driven it and can report that it feels as strong as an ox, and handles – and goes – every bit as well as the owner says. There’s plenty of built-in redundancy in key mechanical components too, and it’s care like that that builds winning vehicles.
Problems? The owner admits that it does leak a little oil but, as every enthusiast knows, “that’s just a TR4 thing.''