It might look more comical than a Space Hopper, but stick a tuned Dolomite Sprint engine into a Triumph TR7, strip it out, add a roll-cage, then stir the pot, and you’re left with a seriously quick trackday weapon.
Words: Keith Adams, Pictures: Alisdair Cusick
Not a standard TR7 by any means, but boy, it is exciting…
IT’S one of the hottest days in the year and our senses are being battered. We’re strapped into its black, tight interior and the noise and vibration is almost unbearable – and yet we’re not even moving yet – we’re at the start line waiting for the flag to drop. This is not our idea of fun. The assignment to meet up with Graham Rimmer and his Triumph TR7 Sprint was typically last minute, and although we had advanced warning warning that the car was ‘a bit handy’, it soon became obvious that this descriptive word was a little on the conservative side.
Arriving after the Javelin track day session at RAF Barkston Heath airfield, near Grantham, we have plenty of time to see the Sprint strutting it stuff on circuit. Admiring the way in which the little green wedge was changing direction, drifting deftly this way and that, then squirting from corner to corner. It was obvious, this TR7 was a more than ‘handy’ – it was pretty special. Back in the Seventies, the Triumph TR7 didn’t carve itself a reputation for being quick. On top of that, its handling was never considered anything better than average, so looking at the way Graham’s car was bounding around the track, it was hard not to be impressed.
After a few hot laps, Graham pulled into to the pit lane, and as his Sprint pulled to a halt, electric fan whirring away noisily, he was he was grinning from ear to ear – and we could see through his full-face helmet. Obviously the driving experience was as fun as it looked from the touchlines.
‘I’ve not been pushing too hard, as the semi-slick trackday Yokohamas are not up to temperature yet”, Graham laughed. Obviously this TR7 deserved closer attention.
Although the carefully applied British Racing Green paint and diamond white viper stripe look fantastic on this fine piece of carefully crafted Harris Mann wedge-work, it’s the Rimmer decals and various other stickers that will cause anyone within 50 paces to come in for a closer look.
Even after 30 years, there’s no escaping the TR7’s arresting shape. Forget the bulky bumpers, and concentrate on the shovel-nose and high tail – along with the dramatic plunging waistline – they are features that remain unique to this day. Traditionalist Triumph fans might miss the delicacy of its predecessors, but for people of a certain age, Graham’s pocket rocket is really going to press some buttons. After all, Purdy had one.
It might look good, but it’s difficult not to be impressed by the sheer scope of the modifications made to this car. Although Graham is a joint mastermind behind Rimmer Bros, the biggest supplier of Triumph and classic Rover parts in the UK, he didn’t build the car himself by raiding the company parts supply. ‘I actually bought the TR7 Sprint pretty much ready built from a Triumph enthusiast, and Touring Car ace, Julian Gammage. I’d been considering building a competition car for several years, but because the business takes up so much of my time, I never got round to taking the plunge,” Graham explained.
It was by chance that Graham managed to buy the car. ‘I spotted it in Autotrader – and it seemed perfect – almost too perfect – as it was exactly what I was looking for. Julian and I struck a deal, and since then I’ve only made a few small modifications to the car where they’ve been needed.”
Ironically Julian bought all the major parts for the Sprint conversion from Rimmer Bros, including all the parts found in the catalogue that are unique to the TR7 Sprint. ‘It doesn’t surprise me that Julian came to us – we’ve sold hundreds of kits over the years.”
A look under the bonnet reveals a professional looking 16V conversion – everything is where it should be. The attention to detail is excellent, and the braided hoses, oil cooler and new Sprint tubular manifold integrate perfectly into the roomy engine bay. We especially love the oil filler cap, which is styled to resemble a large Leyland badge – a touch of pure class.
However, Graham’s Sprint isn’t just a simple engine transplant job. ‘Julian was determined to eke out as much power from the engine as he could. The original low-mileage engine was rebuilt, and in the process the head has been seriously gas flowed, and the bottom end’s been lightened and balanced,” he grinned.
‘It’s not lacking in power, that’s for sure. I’ve not put it on the rolling road yet, but it’s got more top end power than any of our TR8s had, and its perfect for track work as it revs so cleanly. Without the rev limiter, it’ll spin round to 7000rpm – but I keep it wound down to 6000 now in the interests of longevity,” Graham smiled. It’s obvious that he loves this engine.
With around 160bhp on tap, there’s no question about leaving the suspension and brakes untouched. The Safety Devices roll cage stiffens up the body nicely, and the lowered suspension with poly bushes and Spax dampers do their job of keeping it all in check. With such a short wheelbase, stiff and controlled suspension and bags of power on tap, we can see why Graham can’t stop smiling.
As the Triumph TR7 Sprint hangs together so well, you’re left wondering – yet again – why on Earth BL didn’t put its own version into production. It came mighty close to doing just that in the early months of 1978 – one BL insider let it be known that he actually wrote the press pack, and was ready to issue them, only to be told the car wouldn’t be launched after all, following the closure of the Speke factory in Liverpool.
That’s all history now – and the big question is does it drive as well as it looks.
After climbing in through the roll cage, it’s a snug fit – and the racing seats with their harnesses pin you in effectively. All creature comforts have been removed – where you’d expect to see air vents and a stereo, you’ll now find a battery of extra gauges. It’s all good news for the committed driver, though, and the small steering wheel and metal-topped gear level fall perfectly to hand.
Fire her up, and the cabin explodes with noise – you don’t just hear the engine, you feel every throbbing pulse through the small of your back. Perfect for getting you in the mood for some action.
Stripped for business…
Driving up to the line, there’s no real sense of performance, and it’s only when the flag’s dropped and Graham floors the TR7 Sprint for all it’s worth that you understand why he’s so sure it’ll outpace a V8. On the semi-slicks, traction is almost impossible to break, and instead it hurtles towards the first corner unfeasibly quickly.
The gear changes look quick, and we can see why Graham is happy to stay with the Dolomite four-speeder.
As we approach the first corner, and the realisation that we’re accelerating rather than braking is getting rather worrying. There’s no run-off area as such, but that long grass by the side of the track is starting to look pretty scary. We don’t so much enter the corner as flick violently, and the sheer amount of lateral grip generated by this car is astounding.
As one corner unravels, another reveals itself, and another deft flick gets us through without a hint of a slide. At the end of the long straight, the effectiveness of the brakes is also revealed as we strain against the harness during a big stop…
Lateral grip is fantastic on slick tyres
Graham shouts something about the tyres now being warm, but he’s barely heard over the roar of the engine. At the beginning of the second lap, he speeds up, and seems to attack each corner twice as quickly. Now the TR7’s sliding, but Graham’s deftly controlling it with a dab of opposite lock here, extra throttle there. He’s placing the car where he likes, flicking it casually with his wrists, and reveling in the TR7’s fantastic chuckability, all the time making it all look so easy…
After three laps on the roller coaster, Graham’s slowing down and we’ve had a whale of a time. There might have been worries before the run, but there weren’t by the end – this thing was fun in great big capital letters. Once adjusted to the TR7’s prodigious lateral grip, it’s amazing how you start to appreciate that BL were onto something with this car – if only they’d developed it half as well as the aftermarket boys, such as Rimmer Bros had done.
Once we’re stopped, and the TR7 starts to cool down, Graham reveals his plans for the car. ‘I’m seriously thinking about taking it historic racing next year. On trackdays, I’ve already embarrassed some pretty quick cars, and there’s so much potential in it.”
He reveals there’s only one upgrade he’d like to add at this stage. ‘I’m looking to fit a limited slip diff to improve the handling,” he grins. We’re left wondering if it can actually be made to go faster round corners.
Not bad for a car that no-one considered a ‘real’ sports car back in the Seventies…
Triumph TR7 Sprint specifications, owned by Graham Rimmer
Standard TR7, re-shelled using a rust-free Californian body. Racing addenda, such as electrical cut off and bonnet tie-downs. HSCC VIF Paperwork, and eligible for Seventies Roadsports and various other classic touring cars series.
1998cc, SOHC Dolomite 16V engine, running twin 48 Jaguar SU carburettors, electronic rev limiter. Piper 285 ‘ultimate’ road cam, gas flowed cylinder head and balanced and blueprinted bottom end with hardened crankshaft. Trick cylinder head water jacket transfer plate and exhaust manifolding unique to TR7 Sprint conversion and supplied by Rimmer Bros. Oil cooler, braided hoses and high pressure fuel pump, uprated oil pump, 12 vane water pump, high torque lightweight starter motor.
Tubular manifold with large bore sports system.
Standard Dolomite four-speed gearbox with overdrive – operated by steering wheel mounted switch. Rally paddle clutch.
All round Spax adjustable dampers and lowered Spax road springs, poly bushes all round, uprated anti-roll bars, anti-dive kit.
Uprated four-pot calipers, big front brakes, vented discs, braided hoses, silicone brake fluid, uprated servo and master cylinder.
Wheels And Tyres
13-inch Cobra light alloy wheels, Yokohama semi-slick circuit tyres.
Stripped for racing. Door cards and dashboard carcass retained. Full Safety Devices roll cage fitted, along with Sparco racing bucket seats, small diameter Momo steering wheel, four point harnesses and plumbed in fire extinguisher system.
Uprated four row radiator, Kenlowe 16-inch fan.
Magetronic electronic ignition kit, high performance coil, spark plugs and silicone leads.
Rimmer Bros, www.rimmerbros.co.uk, 01522 568000.