We all know that the TR7 and TR8 had years of development potential ahead of them, and yet, due to the company’s continual retrenchment, the car was put out to pasture far too early in 1981.
Richard Truett, AROnline’s man in the USA, feels the same, and to prove the point, has created an EFi version of his TR8 to show what might have been had the BL continued with its controversial sports car. It’s a cracker, too…
Optimising, perfecting and enjoying…
THE words ‘what if’ have been – and continue to be – applied to the vehicles of British Leyland more than any other auto maker. BL could have been a great company, it is generally agreed, were it not for bad decisions, bad timing, bad management, and just plain bad luck. Triumph’s star-crossed TR7 may be the one BL car that suffered from all of that more than any other. It has to be BL’s poster child for ‘what if’.
What if the TR7 Sprint had been born on time? What if the convertible and V8 versions had also been launched as planned? What if the exciting Lynx derivative had not been stillborn? All one can do is ponder those questions. But there is one ‘what if’ question that a deep-pocketed enthusiast of the last TR can answer: If the TR7 and TR8 had lived well into the ’80s, how would it have evolved technically? It is possible to at least have an idea what the answer is by updating the TR7/8 with the components BL developed for the Rover SD1 and Range Rover as well installing some excellent after-market performance parts.
And that’s what I’ve been doing with my late build 1981 federal spec TR.
Born in Solihull in September 1981, my car is the 622nd TR from the last built. The Silverleaf DHC was fitted with Bosch L-Jetronic fuel injection at the factory – as all USA spec TR7s were that year. From Solihull, then, TR7 VIN 407912 made its way to the United States, where it accumulated just 46,000 miles in 24 years under the Californian sun.
I found it in 2005 one restless day at work while surfing the Internet. It was being sold by a charity for $2500; the original owners had given it away for the tax write-off. After a quick phone call, I paid the asking price, and the car came to me in Detroit three weeks later. Aside from a dead battery, the car was in good mechanical shape. It had zero rust, but a terrible paint job and some other cosmetic deficiencies. Since then 407912 has completely restored cosmetically and has been taken on a wild ride in effort to answer some of those ‘what if’ questions.
The original fuel injected TR7 2.0-litre slant-four was smooth, quiet and well-behaved. Yet, with only around 90bhp, it did not deliver performance befitting a proper British sports car. When I found a rebuilt Triumph Dolomite Sprint 16-valve engine in standard tune on eBay in Arizona, the original 8-valve 2.0-litre engine gave up its berth. Performance under Sprint power was marginally better. Since I was driving the car and winning trophies and British car shows, I decided to keep the TR on the road while building a high horsepower Sprint engine, one with a performance cam, oversized pistons, modified head and HS8 carburetors. I wanted 180bhp, figuring that would give the TR the respectable performance and the uniqueness I craved.
That plan was carried out in due course. Still, the results were not quite as I had hoped. The only real way to get the TR to perform well with the new engine was to rev the daylights out of it. The enhanced Sprint engine came alive between 3500 and 6500rpm. While that was exciting, it got tiresome to drive the car that way for long periods of time.
So now the way forward was clear: 407912 would receive a V8 – a Rover V8, of course. With 407912 wired and plumbed from the factory for Bosch fuel injection, here was my chance to take full advantage of BL’s 1980s and beyond parts bin. I could now build a TR that would give a glimpse of how great the car could have been had it lived into the late 1980s.
TR fans will know the fuel injected TR7 and TR8 came equipped with a special petrol tank containing a swirl pot, and a wiring harness designed for Lucas-Bosch L-Jetronic fuel injection. The federal fuel injected TR7s and TR8s were not developed for performance. The ‘flapper’ style injection system used on these final TRs enabled them meet strict federal emissions standards, but did little to enhance performance. A USA spec factory fuel injected 3.5-litre TR8 produces a measly 133bhp. To my way of thinking, that meagre output could be rectified by taking advantage the Rover parts bin. Instead of a 3.5, I could use a later 3.9-litre Land Rover engine, which can take the stock TR8 oil pan, accessory drive parts and other items with little or no modifications.
Back to eBay I went, patrolling it like a hawk and picking off everything I would need for a clean, complete V8 conversion using Triumph and Rover parts. First came the engine. For $705, I bought a complete 3.9-litre from a crashed 2002 Land Rover Disco. I had it rebuilt, a mild cam installed, and all known weaknesses rectified by Mark LaGrue at D&D Fabrications north of Detroit. D&D is perhaps the world’s foremost authority on the ex-Buick aluminum V8. I told Mark I wanted 250 smooth, quiet and reliable horsepower.
Then from rusted out TR8 in New Jersey, came the special V8 subframe and power steering equipment. eBay UK contributed the V8 bellhousing, a EFI system from a 1992 British market non-cat Range Rover. I also bought Rover SD1 4-pot disc front brakes and other parts. During this time I became good friends with Mark Bradshaw, an engineer at General Motors who had converted his own TR7 to TR8 specs and had the same idea: to install fuel injection.
Looking at the professional job Bradshaw did on his car convinced me he was the right man to do the fuel injection installation on my car. His shiny black TR7 V8 was the nicest TR I’d ever seen. Every wire connector, grommet, bracket, nut and bolt were factory looking. My car went to Bradshaw’s garage in late October of 2009, not only to install the fuel injection system, but also to rectify a lot of the sloppiness I committed when I installed the V8 powertrain.
The fuel injection system we used is the hotwire system installed in Land Rovers from the late 1980s to the mid 1990s. It’s more efficient, modern and tunable than the flapper system that came before. Of course, the injection intake manifold and plenum will just bolt right up to the Rover V8. But the system will not easily fit into the engine bay of the TR7/8. Major and extreme modifications must be carried out, jobs that cannot be done by the average hobbyist in the garage with files, hacksaws, benchgrinders and hammers.
When it comes to building engines and cars that are super reliable and professional looking, I have not met anyone more meticulous than Bradshaw. Not only was that a major plus, but I had the added bonus that Bradshaw knew his way around the TR7/8. So when he told me he could do the fuel injection installation so that it looked like it belonged there, looked like BL and Triumph put it there, I was ready to hand over the keys and a blank cheque.
The Rover injection plenum would need to be lowered so that the stock TR’s bonnet would close. The fuel injected TR8s had the air box on the right-hand side, but Land Rovers and SD1s had the box on the left side. That posed a problem. Putting the system in with the air box on the left would interfere with the bonnet stay. Putting on the right meant modifications to the wiring harness and fuel rail. None of this bothered Bradshaw. The plenum and related parts went off to a friend in the GM empire with access to a million dollar machine in some prototype parts fabrication operation. It came back shorter and ready to bolt on. Bradshaw made a new wiring harness using GM connectors and carried out the modifications to the fuel rail. The electric fuel pump is stock TR8 injection. But new hard steel fuel lines were created here in Detroit. A new speedometer cable that accepted the speed sensor was also custom made.
In early January, Bradshaw called and said the car was ready. It was better than I expected and imagined in every way. The Rover ECU was tucked under the glove box, right where it would be had Rover put it there. Bradshaw discovered a Cadillac bracket would perfectly hold the ECU in place. He also raided auto parts stores to find hoses with the proper bends in them so that there would be no kinks or leaks. The cooling system is now fully electronic, with an electric fan that varies its speed based on engine temperature.
By now you are must be wondering if I am going to tell you how the car performs. Power now is in the 280bhp range – which is plenty for the TR’s chassis. My car has been fitted with lowered springs and thicker front and rear anti-roll bars to go along with the beefed up brakes. So, it can handle the added power safely and with predictable control. With modern fuel injection, my TR8 is like any other car these days. You don’t start it so much as you just turn it on. The Rover V8 fires instantly and settles into an extremely smooth idle right away. Cold or warm, the car instantly ready to give its all. And it has plenty to give.
One change I made after getting the car back from Bradshaw was to hit eBay UK once again for a modified ECU. I replaced the Range Rover ECU with one tuned for a 4.0-litre TVR Chimaera. That made a huge difference, waking up the engine and giving it considerably more punch. The engine is not even working up a sweat motivating the 2300lb TR around. Third gear is the most entertaining, delivering strong performance from 20mph to 65. Except for tubular manifolds, the exhaust system is standard, so the car is quiet. And because the engine has bags of torque, the car doesn’t have to be flogged mercilessly to coax the best performance. I have not put the car on a rolling road or measured its 0-60mph time. But I can tell you that my TR8 has now reached its full potential, achieving that rare balance of power, performance, reliability and control. It pulls cleanly in any gear thorugh the standard TR8 3.08:1 rear axle.
If the TR7/8 had lived into the late 1980s, it could have truly been Britain’s Chevrolet Corvette. BL had the parts under development to dramatically improve the car’s performance and handling to world class standards. Perhaps there might have even been a twin plenum TR. And while it may be a small tragedy that the TR didn’t evolve, Triumph and BL did leave us with the bones of what can be a very decent and modern sports car and a fully stocked parts bin from which we can raid to build the TRs of our dreams.
- All the cars I’ve owned : Austin Allegro 1500 Super - 7 June 2021
- Car of the Month : June 2021 – Stephen Wright’s Rover 75 Tourer - 3 June 2021
- Concepts and prototypes : BMC 10X (1968) - 1 June 2021