Familiar to most of us, this narrow angle "V6" has quite the interesting story. The famous VR6 has been revered not only for historically changing the way we see the V6 engine, but for being reliable, modifiable, powerful, compact, and better than pretty much any other V6 that came out of the 90's.
What makes the VR6 so interesting is the way Volkswagen crammed both cylinder blocks under the same cylinder head. You see, the banks are offset so that this can be made possible, technically not qualifying it to be an inline 6, but its also not quite a V6 either. In German, the word for inline is Reihenmotor, designating the inline six as R6, respectively. So if it is not a V6, or an R6, but somewhere in the middle, it must be designated as the... VR6. Let me illustrate how this works with a few photos from it's Wikipedia page.
If the pictures do a sufficient job of explaining this, you can kind of see the ingenious engineering behind this marvel. The VR6 was then compact, lighter and smaller, and cheaper to manufacture since the cylinder rows shared parts like manifolds and the entire cylinder head. One of the problems they ran into was the imbalance in pressure due to uneven manifold lengths for the opposing cylinders (see picture 1). Volkswagen then compensated for this by specifically tuning these intake and exhaust valves, to balance and calibrate each cylinder. The geometry of the uneven manifolds were responsible for the fun sound made by the VR6, often described as a voice of a car with personality.
The VR6 first made in appearance in the Europe-spec Golf Mk3, which outsold every other compact because it was the first offered with a 6 cylinder, while remaining affordable. Later in this series we saw the oddball VR5 variant make an appearance, but that is a different story. After a decade of production, and several modifications and revisions, the VR6 was increased to 3.2L of displacement. Thus, the R32 was born. Most famous for its unique burbly sound, the VR6 being responsible for the sweet song.
Golf R32 Mk4 with the redesigned VR6 in 2001, also equipped with 4MOTION AWD system.
The VR6 was not just used as a performance booster. These things are everywhere today, you can get one for around $1000. It is because Volkswagen put them in just about everything they could. They could outsell other V6s because they were so inexpensive and put out great numbers. The VR6 was put in several vehicles, including the Porsche Cayenne, Audi Q7, Audi TT, Volkswagen Phaeton, Volkswagen Corrado, and today in the Volkswagen Atlas. The final displacement was increased to 3.6L, almost an entire liter up from the 2.8L displacement at its birth.
Australia-spec Cayenne with the equipped 3.6L VR6
The VR6 was responsible for other applications of this idea, namely Chrysler, Ford, and Buick. The Volkswagen W12 Supercar was also technically birthed from this, having an engine derived from two VR6s essentially bolted together on end.
Cutaway of the 30 degree angle VR6
Personally, I appreciate the historical significance of this engine. I truly admire the ability to rethink the status-quo, and just reinvent the wheel so to speak. Volkswagen really took this project seriously, and it definitely paid off. The sheer quality and advancement of this technology has proven itself standstill, the iron chunk was developed in the late 80's and is still in production today. That's just incredible, no matter what you believe is a long time for technology to stay up to speed with fast-changing currents. True problem solving leads to pioneering technology, and as a Engineering student that is something that leaves me in inspirational awe.
What engine do you want to see make a comeback? Leave a comment below!