As with all eight Volkswagen Golf iterations, the fifth-generation model spawned multiple performance versions. Pictured here is the most performing of the lot, the R32 with its naturally aspirated 3.2-litre VR6 engine making just under 247 bhp. However, we're learning the engineers from Wolfsburg had an even spicier flavour in mind. No, we're not talking about the GTI W12-650 as that was only a bonkers mid-engined concept.

In an interview with The Intercooler, Marcos Marques, Project Manager eFuels at Porsche, revealed VW once built a fifth-generation, all-wheel-drive Golf with a V10 engine. As with all Mk5 models sold to the public, the engine was mounted transversely at the front. The Lamborghini Gallardo and Audi R8 had the naturally aspirated V10 installed longitudinally, behind the seats.

Volkswagen Golf V R32
Volkswagen Golf V R32

Although Marques wasn't directly involved in the project, he believes the project came to be at a time when the VW Group was supposedly interested in rejoining Formula 1. The engine had somewhere in the region of 500 bhp and revved all the way up to 8,200 rpm. He spotted a running prototype at a secret facility in Wolfsburg: "I saw it and I heard it running a few times, and it was quite a crazy car."

Aficionados know the VR6, V10, and W12 didn't represent the end of Golf projects with interesting engines. In April 2014, during the days of the Mk7, VW unveiled the R400 concept with a 2.0 TSI dialled to (yes, you’ve guessed it) 400 bhp. In the wake of the costly Dieselgate, the project was abandoned. There was even a prototype running around the Nürburgring with Audi's inline-five engine for an alleged Golf R420, but that never happened either.

Speaking of Audi and rumours, legend has it that VW wanted to borrow the turbocharged 2.5-litre for an amped-up Golf R Mk8 but the Four Rings refused. The reasoning was obvious as a five-cylinder Golf R would've cannibalised sales of the RS3.