There was a moment, right after passing the 140mph mark on Bruntingthorpe's back straight, when I began to realise just how far the Sin R1 road car has come in its short life.

I last saw this V8-engined, 444bhp sports car at Autosport International in January and, to be honest, was a little disappointed not to see a finished product. With the R1 racing car already finished and ready to race in the GT Cup, I'd expected to see the full R1 road car – but instead the firm showed a hollow prototype, a body with no engine or interior.

Nevertheless, nine months later an almost-complete car is hurtling around the Leicestershire aerodrome. I say ‘almost-complete’, because although orders are being taken this is still described as a pre-production model. It's about 95 per cent there, Sin boss Rosen Daskalov tells me. The interior, mechanicals, shape and panels are as customers would see them. What remains is to lift the fit and finish.