Chevron B38
Restoring racing cars is often a clean-sheet process, but this Chevron B38 was a barely-used 44-year-old timewarp. Its restorers had to prepare it for track battles while preserving incredible originality
There’s a school of thought, with racing cars, that you just jack the chassis plate off and build a new car around it,’ says restorer Simon Hadfield as he reflects on the crucial difference between this Chevron B38 and many of the world’s active historic racing cars. ‘But to us, restoration is everything. Unless you can sit where your hero sat, then there will always be trauma between competitiveness and originality.’ For owner Neil Jenkins, restoring and racing this Chevron was a unique prospect. ‘I went to Bolton University as a young man, and lived 100 yards from the Chevron factory,’ he says. ‘My wife and I met there in 1977, and this car rolled out of that factory in that era. I saw it for sale and had to buy it!’
The car was originally supplied to Italian privateer and future Osella Formula One driver Beppe Gabbiani, who used the car in the 1977 European Formula Three Championship, finishing fourth overall, seven points behind Nelson Piquet, after a promising start that saw him win at Paul Ricard. However, mid-season he crashed his original B38, and bought this one as a replacement for the rest of the year. But after mere months, the car was shelved.
‘It was because of ground effect,’ explains Hadfield. ‘It was brought into F3 for 1978 and this B38 became obsolete overnight. The only forum to use them in really was hillclimbing, but instead this car was just pushed into a corner of Gabbiani’s garage.
‘It was an unloved orphan until Neil, who previously raced Morgans, came along and fell in love with the car and its history. He wanted to race, but was also taken in by the romance of the project, which left us in a unique position. It needed to be competitive, and yet 95 percent of this car was all-original and needed preserving.
History and originality like this makes restoration so much more rewarding.’
Assessing the project
‘When we strip down a car and examine each part, we have three criteria we apply to it,’ says Simon: ‘First, it must be safe. Second, it must be competitive, and third, it must be nicely presented. Certain parts, you simply can’t use. We took the stressed parts of the chassis to NDT Services, part of Rolls-royce Aerospace’s facilities at East Midlands Airport nearby, and subjected them to Non-destructive Testing, essentially airframe ultrasound and liquid-penetration stress analysis to work out what condition the safety-critical parts were in, scanning them to determine whether they’ll stand up to the pressure of racing or not without damaging them. They gave us a written report, allowing us to work out what we could reuse and what we couldn’t. Sadly, this meant we lost some of the drivetrain and the wheel hubs, but it is 45 years old after all!’ The weakest point was the adaptor plate linking gearbox and engine.
‘Unfortunately, when we studied period photos of the car we realised that the rear wing assembly was completely wrong, so I borrowed another standard B38 from a fellow historic racer so we could reverse-engineer it and put it right,’ says Hadfield.
Chassis and structure
‘Incredibly, the only chassis tube we actually had to replace following stripdown was the dashboard hoop,’ says Hadfield. ‘This was mainly because it had been very badly plated when new. The restoration process was carried out by Nottingham Platers, which uses a combination of reverse electrolysis and acid to remove chrome plate, but crucially they do it gently and gradually. This gives the ability to expose the metal underneath the plating without damaging it. Over the years I have seen firms use dechroming processes so aggressive they’ve ended up damaging the very metal the restorers have been trying to save.
‘I made a jig based on the dimensions of the original hoop, and derived the new section from that, before the whole thing was replated by Nottingham. We use nickel – not only does rechroming cost so much nowadays, it’s also no longer allowed in motor sport. Nickel keeps the chassis legal while still looking original.’
It wasn’t the only challenge of balancing modern motor sport regulations with classic aesthetics. ‘Seatbelt regulations have changed since 1977,’ says Hadfield, ‘but I had to integrate what was necessary with originality, so while the roll bar had been removed, I welded modern seat belt mountings in beneath. The Willans harnesses look great – the brand the car used originally, but although they’re new, they’re low-key and don’t visually jar.’
Solving the issue of the worn adaptor plate and casing linking the engine to the gearbox was taken on by owner Neil Jenkins. ‘There was broken and rewelded magnesium, rendering it almost completely unusable, but replacements for parts like these are like hen’s teeth, and it’s a crucial part because the rear suspension also hinges off the casing,’ says Jenkins. ‘However, fabricating unusual parts is nothing new for me – my firm produced amphibious vehicles! So, through Simon I got hold of Chevron’s original drawings, I made a pattern from them, cast a replacement in aluminium and machined it to fit.’
Wheels, suspension and brakes
‘Trivellato, Chevron’s Italian importers, always changed the wheels to Speedlines when the cars arrived – they were cheaper, and easier for them to deal with as an Italian company,’ says Hadfield. ‘However, as the cars were used, crashed, and modified over the years, the Speedlines have become very rare. This car was wearing its original wheels, so keeping them and getting them race-ready again was important.
‘We crack-tested them at NDT Services to ensure they weren’t structurally compromised, then bead-blasted and treated with etch-primer before painting to ensure they won’t be affected by brake fluid, and can be washed in future without worrying about degrading. Two needed new centre splines, from MB Wheels, but we managed to preserve them.
‘Also, now we have these, castings can be made and so can replacements. If they get damaged in future we can replace them, but recreating these Speedlines is now a real possibility. With this level of car, £5000-£10,000 is a big cost to amortise in terms of creating castings, but when you bear in mind that every Chevron that went to Italy got them, plus all the Italian cars that had a set when new, there’s a big market for reproductions. Give it time…’
Dealing with the rest of the suspension and brake assembly was relatively straightforward by comparison. ‘The driveshaft constant-velocity joints are off-the-shelf Volkswagen parts, so they were easy to replace,’ says Hadfield. ‘However, the driveshafts themselves are bespoke Chevron parts. Thankfully, NDT revealed them to be resilient, so they could be reused.’
The aluminium brake housings required a more delicate approach. ‘The brakes needed new pistons and seals, but crucially the housings had to be restored – we could keep the originals if we were careful,’ Hadfield explains. ‘We don’t like to sandblast aluminium – as with dechroming, being overly aggressive when attempting to remove surface corrosion can end up damaging the thing you were trying to save. So we put them in Altrans, an acid descaler that can be diluted to adjust the strength of the process
‘The sheer number of bleeding fingers as a result of cleaning the original body tub. But we had to save it – Beppe sat here’ Simon Hadfield
‘Beppe getting in touch on Instagram when the restoration was finished and saying “Fantastico” – that meant a lot’ Simon Hadfield
required. By contrast, once you’ve sandblasted bare metal, you can’t touch it without damaging it so it then needs special coatings to protect it. That wasn’t the case with these housings – and we wanted them to look like they did in 1977.’
The original Bilstein dampers were in good condition, although they needed a different approach to when they were new, as Hadfield explains, ‘We had them dyno-tested and serviced by IG Racing. Nowadays though, even classic F3 cars run lower and stiffer than they did in the Seventies. We wanted more rebound, but unlike modern racing dampers these Bilsteins aren’t adjustable, so they had to be just right when they went on the car. We’re not re-inventing anything, it’s just about bringing what we’ve got up to modern specifications. Back when the car was new, Bilstein had a caravan in the paddock servicing them. That’s no longer available, so we have to send them away.
‘They’re running 50 percent stiffer than they did when new. Circuits are smoother-surfaced nowadays, and big kerbs have disappeared so tracks can accommodate motorcycles, so what we ask of racing car suspension is very different compared to 1977.’
Bodywork
Although it had only seen half a season of competition, the glassfibre bodywork and central tub were a long way from how they’d appeared in 1977. ‘There seemed to be a million coats of paint on it!’ says Hadfield. ‘When Gabbiani raced it for the first time, at Monza, it was blue, but it replaced his previous B38, which was red. It seems he later repainted it, and it changed colour again around about the time he sold it. You could practically trace its timeline by taking its paint off. There were at least five layers.
‘Not only did we want to return it to its original appearance, there’s also competitiveness to bear in mind. Paint is heavy – a paintjob on a car like this weighs 15-16 kilograms. Then bear in mind that new competition cars are typically delivered on their legal weight limit. ‘The solution was for glassfibre specialist Dave Rose to go back to the original gel coat, where the glassfibre was originally colour-impregnated, using a powered orbital sander.
‘There were cracks to address – they tend to appear at the rear of the cockpit surround, where drivers brace themselves getting in and out, and wheel-mark damage to the sidepods where Gabbiani had clashed with rivals – but Rose did wonderful work. The technique when repairing racing-car glassfibre is very different from road cars. When adding in new matting, you don’t build up excessive layers but work in just enough within the confines of the original gel coat to avoid adding weight.’
Getting the precise Monza appearance was a question of studying photographs. ‘Big computer screens helped when it came to recreating the livery,’ says Hadfield.
‘The Italians were way ahead of the rest of the world in the Seventies with liveries,’ says Hadfield. ‘They used stickers when British teams – even in F1 – were still hand-painting liveries. It meant that sponsorship logos could be changed more easily, rather than employing a signwriter. It’s entirely possible that this car never ran quite the same livery twice. We used those photos from Monza to recreate the decals that we needed on a computer, then sent the data off to Coalville Signs to remake them for us in vinyl. Coalville’s main business is making livery decals for Police cars, so this was a fun diversion for the people there!’
Sadly, the nosecone had suffered a frontal crash at some point and was too damaged to save, so a fresh replacement was needed from Chevron. However, there was one part of the bodywork Hadfield refused to compromise on – the central tub. ‘There was nothing special to the techniques involved in bringing it back, just lots and lots of elbow grease,’ he says. ‘I went crazy with the Scotchbrite pads and WD-40, taking it back to its original finish and cleaning off all those years of dirt and neglect, until my fingers were bleeding. It would have been easy just to order another tub from Chevron, but we had to save this one – Beppe sat here.’
Engine
The engine, a ubiquitous-for-1977 Italian-built Novamotor Toyota unit, was rebuilt by Stuart Rolt. ‘It’s the oddest bit of the car, in a way,’ says Hadfield. ‘The whole engine is effectively controlled by a 24mm air restrictor. The result is no useable power below 4700rpm, and then it delivers maximum power at 6000rpm. And it’s all analogue. The Kugelfischer fuel-injection metering unit is clever, increasing pressure naturally, but it can only accommodate so much of what the engine needs – over 6000rpm they start overfuelling. It was used both on BMW’S road cars and Mark Donahue’s racing Porsches in this era.
‘Upon stripdown, the engine was in remarkably good order inside. A combination of an understressed 160bhp and huge torque means they don’t tend to suffer. We gave it a modern starter motor though – the Denso unit we’ve fitted is so much better than the period Lucas. Mechanics used to change them every race, they were practically disposable.’
The eagle-eyed will have spotted an oddly domestic addition to the Chevron’s air intake. ‘It’s a tea-strainer!’ says Hadfield. ‘The front wheels flick stones up, one of the drawbacks of modern racetracks is that while the kerbs have gone, gravel has arrived, and all it takes is a pebble to go into an open air intake and you’re looking at an engine rebuild. Hours were spent on Amazon trying to find just the right diameter of stainless steel tea strainer to adapt to use as a protective mesh. As soon as you go looking for bespoke sizes there’s an assumption you want something posh and all the ones you’re offered are finished in brass!’
Brass wasn’t an option in terms of cooling the engine. ‘The radiator’s new,’ says Hadfield. ‘Radiator-building is something the UK automotive industry is excellent at, but we couldn’t afford an original-style brass one for this car – it’d have to be Aston Martin Dbr2-level to make sense to build one. Instead, we got this one from Radicool. Lighter, cheaper, and just as effective.’
Back on Track
‘When a car you’ve restored leaves the pits for the first time and does exactly what you want it to, that’s a special moment,’ says Hadfield. ‘We took it to Mallory Park for testing, put it on Instagram, and had an unexpected reply – from Beppe Gabbiani – reading “Fantastico! I’m so happy, it’s so nice and beautiful.”’
Neil Jenkins was just as impressed when he took it on track for the first time. ‘Simon kindly let me drive his Formula Ford during the restoration so I could get used to a rearengined single-seater. But those are smaller, with treaded tyres. I’m just getting used to the Chevron, but it’s far more capable than I am.
‘I am immensely proud of where it is now. It’s like new, but it was a proper restoration rather than just buying parts and bolting them together. But I bought it to enjoy, and that’s what I’m going to do with it.’