Pushing any Vauxhall engine to the limit isn’t easy, but after seven years, Gareth Chapman has built one of the highest spec C20XEs in the country.
PHOTO Chris Wallbank
* QED throttle bodies on dry sumped XE
* Quaife straight-cut gearbox
* Polycarbonate windows
* Kevlar bucket seats
* OMP roll cage
I have been writing about Vauxhalls since 2005. During the last eight years, I’ve typed the tale of all sorts of cars, from classic Vivas right up to the latest VXR8. Looking back through old issues of Total Vauxhall, I think to myself, one day I will go through them all and make a record of each and every car I’ve written a feature about. I suspect (though I have no proof) that the most popular car will be the Nova. And I’ll tell you what, eight years is a long time. Things have changed a lot.
The Nova was old, even back then, but fashions were a lot different. Styling comes, and then it goes. But one thing will never change – it’s been the same ever since those noble pioneers first starting shoehorning big, two-litre motors into Novas at the start of the ’90s. The insatiable, uncompromising, all encompassing need to make the little cars go as fast as possible. It’s a job that will never end – style is temporary, performance is permanent.
As you may have guessed, the Nova featured here is not messing about. The powerplant of choice is a very high-spec XE, which is probably not too far off early touring car power. It has been built to not only tear up the dragstrip, but also to tackle corners with equal ferocity.
The story began with a stolen recovered Astra Coupe. Owner Gareth Chapman had bought himself said Astra, having owned a couple of Novas previously. The Astra was the “nice” car. At least it was until he came back from walking a friend’s dog one day to discover that the Coupe had been nicked again, never to be seen again. “The police weren’t bothered, they just got me to fill in a form,” he muses.
With that, Gareth decided he wanted another Nova, so went straight out and bought another stolen recovered one. In a roundabout way, the actions of some scroats actually benefited Gareth this time around. The car in question was a Cat C Nova SXi, in superb original condition, needing only a set of door locks and costing just £150. Another unexpected bonus of the Astra going AWOL was that he inherited a company van to use, so the Diamond Black Nova could become a project car.
Right from the start, a 2.0 16V was the engine of choice, and it was immediately fitted with a pair of Autosprint cams and treated to a remapped ECU. The upshot of this was an extremely healthy 170bhp, and an impressive 13.8-second quarter mile time. Of course, this level of power was never going to be satisfactory for long, and six months later the car was pulled to bits.
Throttle bodies were bought, the car sprayed a Nissan blue colour and an engine “in bits” was sourced. This time 194bhp was achieved, but the engine only lasted three weeks. “The crank wasn’t ground so it properly knackered the bottom end,” frowns Gareth. The initial diagnosis was that it had perhaps only run the big end shells, so they were replaced, only for the engine to promptly throw a rod out of the block in protest. Damn.
“I was two-grand down at that point,” he tells us, “but I wasn’t giving in, I decided that I would start again, and this time do it properly.” A new block, new crank, steel rods, PEC pistons – a huge shopping list – was put together with no expense spared. The new engine was built up and reunited with the throttle bodies. This time round, it worked. Power was the same, at 194bhp, but there were no disasters. The car was taxed, tested and Gareth was having a lot of fun with it on the road and also down at York Raceway.
“The head gasket went on it at this point and it was filling the ports with water,” says Gareth. “But for some reason it went like an absolute beast and ran a 13sec quarter that day! We did have to drive home with the heaters on full though, which wasn’t nice on a hot day, in a Nova with plastic windows.” Gareth got in touch with engine expert Steve Milton who fitted a Roper cylinder head, specced new camshafts and then had the lot bench tested at Hart Transmissions of Essex. Things were starting to get serious. The engine was dry sumped, before a BTB exhaust was added, Cometic gaskets used once more, and the lightest possible flywheel fitted. Steve’s brother, James was also able to source a Quaife straight-cut gear set for the car.
The process took around three months to complete, and the car just missed making it to PVS 2011. It did however, now produce a highly impressive 244bhp and 192lb/ft of torque. Gareth took the car to various drag strip events but he felt that it was losing traction too easily. “The map was too rich, and it was either bogging down or spinning,” he says. RS Tuning remapped the ECU, losing a little power along the way, but gaining a smoother graph. PVS 2012 should have been a good day, and Gareth managed three runs, his best being a 13.5. But, “I split an oil line on the strip and seized the bottom end!”
The motor was sent back to Steve for investigation. The rods had gone blue, the bearings were gone, but thankfully the crank was okay! “I then decided once it was fixed to take it to EFi Parts in Runcorn, who I had heard good things about, I was passed their number by Corsa turbo owner Allan Duthie. They reckoned that the inlet cam wasn’t quite right and was holding the power back,” says Gareth. Steve then spoke to Piper who were able to produce a specific cam. Back at EFi at the start of this year, the full potential of the engine was unlocked, with a storming 253bhp and 201lb/ft of torque. “It feels very quick now, the power is just there immediately and it takes off like a turbo car with 350bhp,” he grins.
Gareth now feels that he’s taken the car as far as he can – it’s pretty much the ultimate incarnation of a big-block, naturally aspirated Nova. “It is probably going to get broken for spares now, but I’ve had seven years out of the car, which hasn’t always been easy,” he says. “I’ve had a lot of fun though, and it will always put a smile on my face thinking about the times when I was sat on the back bumper of things like Bentleys.” And fair play to that.
Wendy my girlfriend, Lee and Jake for all their help, Chris for the paintwork, my bro Ricky for welding seats in at 2am before a race, Paul and all my other mates who helped along the way.