There may have been a time when automakers would develop their road cars first, and the racers based on them afterwards. But that time is coming to an end.

Nowadays, with increased frequency, automakers are developing their racing cars and road cars in parallel… especially when it comes to GT racers. Just look at the new M8 GTE that BMW unveiled in Frankfurt this week, before the road-going 8 Series (much less the M8) is ready for its debut. Or check out the forthcoming Aston Martin Vantage GTE caught testing in this video.

Spied testing at the Rockingham circuit in the UK, the Vantage GTE is still wearing black and yellow geometric camouflage, just like the road-going prototypes we’ve seen to date. But there’s no mistaking this for the competition version, what with the road-scraping ground effects protruding from underneath the bodywork, that giant wing affixed to the rear deck, the blistered wheel arches, and the extra cooling.

The big question is what engine’s under the hood. It sounds more like a turbo eight to our ears, with that throaty roar and telltale turbo whine. Besides, nobody uses a V12 in GTE – they’re just too heavy. For its part, Aston Martin Racing has traditionally deployed a V12 for GT1 and prototype classes, with a V8 in everything from GT2/GTE on down – including the current model that won the LMGTE Pro class at Le Mans this year.

That racer packs a larger version of the automaker’s V8, bored out from 4.3 liters to 4.5. The old V12 displaces nearly 6.0 liters, and the new twin-turbo V12 in the DB11 comes in at 5.2. Either one would need to scaled down to comply with the rule book: no more than 4.0 liters with forced induction, or up to 5.5 without.

Our best guess? A competition-spec version of Mercedes’ 4.0-liter twin-turbo V8, like the one in the eight-cylinder DB11 and expected to power the new road-going Vantage. The Ferrari 488 GTE and aforementioned BMW M8 GTE use a similar setup, but with the Mercedes-AMG GT3 sticking with the naturally aspirated 6.2-liter V8 from the old SLS, the turbo eight would have to be developed specially for the purpose.

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