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Biomech Under The Bonnet

I first featured Jason Shalders and his incredible MG project back last September, following a fortuitous meeting at the Autosport International show at the beginning of that year. His seemingly outrageous plan: to take a classic British sportscar from 1966 and to build a street-legal GT3-spec racer – one that could grab the Nürburgring lap record for street cars. A completely bespoke build, undertaken by a small and committed team, but spearheaded by Jason’s unwavering commitment and passion for the plan.

Six months on and the progress is suitably impressive. The car has been transformed visually, with the almost-complete body panels giving us a proper idea of how the car will sit: low and squat on those enormous O.Z. Racing rims. But it’s up front that I’ll be taking a closer look at in this update – the part of the project closest to Jason’s heart.

Whilst build specialists Chris Isaac and Jedd Guy concentrate on the chassis, body and dynamics, Jason has been building up the brutal package that will become the thumping heart of the MG.

I have to warn you – if you’re an engine fan then you might want to be sitting down for the next five minutes. This hand-crafted engine is a work of art. Now it’s ready to spread its wings.

The inspiration for the configuration of Jason’s V8 comes from Lotus’s own still-born 909 engine project, which was the company’s first attempt at a V8 in the 1980s. The combination of two incline, inline four-cylinders into a classic V8 was created for the still-born Lotus Etna concept car, but then dropped until the development of the 918 for the Esprit the following decade.

There aren’t 909 engines lying around to use, so Jason went with what he knew – the 4-litre Rover Thor block. To that he’d meld two high performance Lotus four-cylinder heads with completely different bolt patterns. And then bolt on a pair of turbos. That’s when the madness started – but it’s a very infectious madness…

So here we are – this is how far Jason has got, with the finish line for the project the start line of the Nürburgring. It’s the result of seven years of blood and sweat. The task of making those iconic Lotus heads work – and not just work, but work in the most extreme conditions – with its unwilling Rover bride can’t be underestimated.

At the beginning of this project, many years back, Jason started with the obvious thing: getting the four-cylinder Lotus heads to actually fit the Rover V8 block, with their completely disparate bolt patterns. Like a surgeon, the only way to find out how something works is to get your hands dirty. After a lot of hard, physical graft, Jason ended up with a stack of chopped up blocks and heads lying about – the detritus of the many experiments that led to the final Eureka moment.

With the optimal solution in mind, he machined out slots to get down to the block’s original holes, then built them back up with the extra width for the new heads, preheating as he went to maintain integrity.

Of course, that doesn’t magically make the two things work together – especially when you remember that one of the heads has been flipped around 180 degrees. The unholy matrimony meant crafting new waterways and looking at all the other important things like oil drain-backs.

Thor might have been the name of the engine, but even Thor needs some reinforcement from time to time.

The standard Rover cast block came cross-bolted and was prone to fractures from the block flexing, not helped by caps that could not only be pushed down by the crank but also move laterally. Jason has fabricated his own custom billet steel main caps, pinned and cross-bolted to counter any vibrations or harmonics that might be caused at the high revs they’re expecting.

New long studs protrude from the base, which will join to a new billet dry sump. The entire collection will then be mounted to the pan ring around the outside of the block and pulled in tight to make one big structural unit. With the power numbers the team are working to, they can’t afford any movement.

Jason’s added a massive amount of reinforcement across the centre of the block, where originally there were just three puny ribs trying to stop the block from punching itself apart and creating two messy inline fours. He’s added significant structural webs, which in itself was no easy task.

Even with meticulous preparation prior to the reinforcement, the nature of the aluminium block meant that it started shifting around in every direction as the welding was applied. Subsequently, there has to be some major machining to bring it all back to dimensionally and physically squared-up proportions.

The first major modification on Jason’s list once the heads were addressed was to sort out the oil supply to the main crank, that gets fed through the pair of galleries in the block. The new overhead cam setup meant that the original followers, pushrod and rockers were redundant – but removing them left gaping holes on the top of the block.

They couldn’t just be welded shut, as that would interfere with the oil galleries, so Jason crafted an elegant solution: a set of two-piece aluminium follower plugs with wasted stems that push in from both sides, cleanly sealing the block without affecting the oil flow.

As with so many parts on this complex engine, this simple and elegant solution came hard. Initial solutions tore their O-rings off on installation or fouled the passages. Create, test, iterate; Jason’s mantra comes from Eddison, inventor of the light bulb. “I have not failed. I’ve just found 10,000 ways that won’t work.”

Along with the dedication to quality on the build, Jason also wants to be able to make the modifications commercially available once the car is finished. The MG is a technology testbed, and having that commercial goal ensures that the bar is always set high. ‘Just about’ isn’t good enough – everything has to be perfect.

With the core engine at a good stage, it was the time to start looking at the surrounding ancillaries, the manifolds and inlets. Getting these parts in place would allow Chris to build the car up knowing the position of the engine’s main components – they wanted an engine that worked for the car, not for the dyno room. It also meant that, like the car, the engine is truly showing its potential character.

There’s just nothing simple when you’ve taken on this kind of project, using proven but old tech. It’s like the trying to fit imperial to metric thing, where almost nothing fits first time. Case in point: the manifolds. The ports were oval, so had to be taken to the round tubes, 316 stainless steel flanges were laser cut, created by Chris and Jedd, to connect to the Inconel system.

Everything has been specified and designed around endurance – this car is true to its principal of the classic trackday ethos, drive to the track, thrash it around, drive home.

Speed and performance are matched by a concentration on safety. Heat flashpoints on the car use appropriate materials, with the team cognisant that even hot gasses from cracked exhausts could trigger major problems – the Inconel exhausts show the pragmatic approach.

Bringing The Hammer Down

Boxes are turning up every day at Chris Isaac’s workshop – the turbos some of the latest goodies to arrive on the day of my visit. Owen Developments have supplied the twin GT35-82 HTA turbos, one of many companies who have stepped up with both technical and product support. It’s that kind of project: you can’t help but see this car and then get swept along with it.

If the spread turbos are things of beauty, then they’re only matched by the magnificence of the Jenvey injectors that cap the whole structure.

Jason knew he wanted a multi-plate inlet, understanding it should drive better and give the pilot more feel – of particular importance when you’re setting your sights on the Norschleife. He calculated the distances for the inlet manifold, using MDF to rapid prototype templates, then worked with the team at Jenvey to design and create the finished units.

Although billet aluminium and steel is used extensively, the cast manifolds met the other criteria for the MG: to retain a classic feel across the car. They look stunning, and again they’re an aesthetic solution to the constant challenge of this engine melange.

Working through options like reducing the height by running lower double injectors or port injectors from the rear, Jason concentrated on getting injectors right into the bell mouth, firing into the trumpets. This way, slight evaporation and expansion of fuel would also create a cooler air charge.

The inlets couldn’t run straight as they’d clash (the 909’s engine ran in a cat’s cradle across the top of the engine, a bit like a Corvette’s), plus again needed to go from round to oval. So the 20-degree curve was introduced to bring them to the vertical – which just adds to the pleasing aesthetic.

With the heads designed to be run slanted over, with carbs also angled, Jason wanted to use individual throttle bodies, with double injectors for cooling, two per cylinder for the ignition stages.

Technology has snuck in here though. Off to one side is the fly-by-wire throttle system which will link to the seamless shift, paddle-shift-controlled gearbox; anti-lag comes as an additional benefit.

The idea is for the engine to rev fast and freely up and down the range, almost like a bike engine, so Farndon have created a compact flywheel to the team’s design, backed up with a five-inch clutch plate.

The liners were another present just unwrapped, delivered from Westwood Cylinders, and should now have been dropped in. As is the norm for this build, they were slight variations on the stock item, created in partnership between Jason’s team and the company.

Harmonics dampening across the rev band will addressed care of this substantial Fluidampr viscous damper unit.

The beautiful Arias piston heads (yes, modified specifically for the MG) are covered in a protective ceramic top application, with a Moly coating around them to prevent wear on the bores. They come with standard twin rings and oil scrapers, plus fully floating gudgeon pins on the inside.

The MG’s ECU is still at the discussion stage: it’s a big decision as it’ll need to work with everything else on the car. The team want to avoid duplication where possible, so ideally sensors will be shared between systems – the car will be laden with a full suite of data-gathering and monitoring sensors.

The car will end up with three wiring looms: one for road use (indicators and so on), one for the engine and one for the gearbox. It’ll make changing things easier – which is especially important as Jason is also working on the four-cylinder turbo Lotus engine option.

Based on the Lotus 912, that’s going to be a 650hp screamer. Jenvey are designing bespoke manifolds for it which will work on the horizontal plane rather than the vertical of the V8. But that’s another story in itself!

Jason’s next big project is working on the front cover, designing the layout of all the idlers and pulleys and finalising the dry sump. Wide belts will be used, plus the offset of the engine has to be compensated for. Front pulleys will drive the odd numbers and rear the evens.

Possessed By The Alien

When it gets to the body, the talk is always about air. You get the feeling that Jason and Chris aren’t talking about physical steel and filler, but see the MG as an ephemeral entity, the movement of air and its effect.

From the last time I visited the shop there’s been dramatic progress. The old MG is still distinctly there, but now it’s buried under a mass of battle armour, stretched, widened, flattened. Paint the panels, pop some glass in and you feel the car would just drive itself off into the distance. Of course, there’s still a way to go, but you get the impression that they’re onto the detailing.

Chris was working on the rear tubs, which will be sealed except for the protrusion of the suspension arms. This will protect the inside of the units, and once the charge coolers are in place with their protective grilles control the smooth movement of air up and over the rear arches.

Each area of the car is treated this way, with the aim of creating enclosed packaged spaces that protect their respective components.

The final lines are being smoothed off, then the formers will be sent off to Ryan Ennion at SP Automotive, who’s responsible for all the bodywork. Once everything is signed off, the whole car will be handed over for the final phase of bodywork prep, initially in fibreglass but with the hope of moving to carbon fibre in the not too distant future.

Starting at the front, the massively aggressive splitter dominates the nose. It’s split into sections, so individual parts can be easily swapped when trying out aero configurations. The front air ducts feed the ITG filters, which in turn push high pressure air straight to the turbos.

Behind is the ducting and aluminium Proalloy radiator, a bespoke unit as with so many other components, designed expressly for the MG’s cooling requirements. It’ll be overcooled for the four-cylinder Lotus engine option, but in that case carbon blanking will be used.

Hot air is ducted out over the frankly epic bonnet. With the panel on, it’s like the Alien has pounced onto the nose and buried itself deep down.

The result of numerous iterations, always trying to stay true to the styling spirit of the MG within, this version pushed the vents back slightly, which gave an advantage to the speed of the airflow as well as helping thrown the air up well clear of the engine bay.

There’s space at either end of the MG’s old grille which could be used for brake cooling, plus they may take more air from the underfloor to help cool the turbos. The clear expectation is that with everything going on underneath the bonnet, it’s going to be a potentially volcanic place to be.

Despite the bulge, visibility for the driver is going to be surprisingly good. Race driver Oli Webb, who will be aiming the MG at the ’Ring come the end of the year, reported that sight lines were all fine and that the important bits were in vision. Who cares about what’s behind you?…

There’s still a long list of design challenges ahead – things like the header tank, batteries, wiring, reservoirs, pipe work, alternator, starter motor and so on. But it’s not endless, which must be pretty reassuring for Jason and the team.

A lot is about packaging, like does the pedal box go high or low, which will affect the steering column, which in turn affects the manifolds. But this interconnection helps in a way, as each step can tick off multiple questions.

The big question remains though. How will it perform? That aim of beating the cream of the hypercar world in what they want to claim as their own backyard is crazy – a bit like the idea of jamming two completely different engines together. But the latter will work… so why not the former?

Jason’s dedication and passion hasn’t been exhausted – if anything he’s already finding new things to add to the project – and this 50-year-old MG looks almost ready for battle. Later this year we’ll get the answer. I think they’ll be a lot of people in a lot of boardrooms who are getting a little anxious…

Jonathan Moore

Instagram: speedhunters_jonathan

jonathan@speedhunters.com