Why BMW Hates V6 Engines

BMW has made V12s, V10s, V8s, inline sixes, four pots, even three pots, some of the greatest engines ever. But there is one engine layout that's missing from their lineup, one that virtually all of its competitors have developed at some point. Why has BMW never built a V6 engine? We'll dive into why BMW has never bothered with that engine layout and also uncover an engine story that I reckon BMW and another manufacturer really don't want you to know about. Six cylinders in a V layout is a hell of a convenient engine to put into a car. This is one of mine. They're good because they can create decent power, spreading the load over those six cylinders. They're also quite compact, being the length roughly of a three-cylinder engine, and they're quite narrow, normally being 60 degrees versus 90 degrees that V8s normally are. That compactness means you can mount them either longitudinally or transversely in an engine bay, and given the right exhaust, they can sound insane. It all sounds great, but as I've spoken about in the past, the transverse V6, like in this car, is completely dead. The turbo four-cylinder killed it off. If you want to watch the video I did about that, click the pop-up banner up there. Saying that, V6s in their more normal form, longitudinal, are very much still alive. In fact, Ferrari and McLaren recently put V6s in the back of their recent supercars, the 296 and the Artura. V6s have been in some of the greatest cars ever made, the Honda NSX, Nissan GTR, 4GT, and yet, the guys and girls making the ultimate driving machines have never bothered putting one in their cars. Why? Well, they're so bloody good at making these things. BMW are one of the best in the business at creating straight sixes, the M20, S50, M54, S54, B58. Wikipedia tells us that BMW has created 23 different variants of straight six engine, and across the board, they're supposed to all be pretty damn good. Their traits include good power, decent torque, okay reliability, minus rod bearings, and some of them rev nice and high too. Straight sixes are generally chosen because they are perfectly balanced. If you split the engine right down the middle, three on one side and three on the other, the pistons move up and down the cylinders with their mirror image on the other side. Combine that with the ideal firing order of and the reciprocating forces balance themselves out. That means you don't need any balancing shafts or dodgy firing orders to make the thing run. It runs super smooth, which means you don't have any unwanted vibrations, which means you can up the revs and therefore, up the power. They're also simpler. A dual overhead cam straight six has one less cylinder head and two less cam shafts than a dual overhead cam V6. That means theoretically, there's less to go wrong. Also, in these modern times where engineers want engines to be modular, you can develop your straight six but also develop an inline three, four, or five while you're at it. BMW famously make their cars quite easy to work on for mechanics, leaving certain spaces and holes for tools to get into, and a straight six also helps as well. Because it's nice and vertical, you can get your arms down either side and get cracking with any maintenance you need to do. Basically, on this engine, if you take the intake off, you suddenly have access to all the engine gubbins below. The engines are canted over, but this side is all just exhaust manifold. Really, most of your maintenance, you're going to have really nice access to it. If you compare that to the V6 over there, with that engine splayed out, there's nowhere near the same amount of room to get in amongst it and fix what you need to fix. Let's take a job as simple as spark plugs on this BMW straight six. They're right there, ready to access, while on my V6, that rear bank is notoriously a pain in the arse. Some of you guys may have noticed over the years, I'm quite bald. I'm 30 now, but I remember being 20 and giving up trying to get haircuts that covered up my receding hairline, and I just shaved it all off. Looking at our demographics, I imagine a bunch of you guys are potentially going through a similar situation now. It got too late for me. As you can see, my hair is gone. It's probably not too late for you, and that's where the sponsor of today's video, Manual, is here to help. Manual is a UK men's healthcare company challenging the outdated notion that real men shrug their shoulders and carry on. Their hair loss products help prevent further hair loss and aid in regrowth. You can start seeing results within six months. Here are a bunch of before and afters. You'll get access to a clinician who will monitor your progress, adjust your plan based on your needs and goals, and offer 24-7 support via video calls and WhatsApp whenever you need. I remember the days of stressing about how my hairline looked and lacking confidence, knowing that I was giving off a vibe that I was trying to cover something up. If you are going through a similar situation, there are solutions. Click the link in the description below and see if Manual can sort you out. To get 55% off your first hair loss treatment, use the discount code DRIVETRIBE55. Although V6s very much have their advantages and virtually every other manufacturer has put them in their cars, BMW never justified switching from their straight sixes into a V6. There was no need. Their straight sixes were so good that they simply engineered their cars to have long enough bonnets to accommodate them, and they've kept cracking on ever since. Dara at Everything M has kindly lent us this E34 M5. What a motor in this thing. It's so long-legged and it revs so freely, everything we've just been chatting about. What a beautiful piece of kit, so elegant, effortlessly doing exactly the speed limit. If you owned one of these kicking about in the early 90s, you were pretty damn cool. It doesn't matter that every other manufacturer has used V6s in their cars, BMW has never needed to bother. If you need a more compact engine, use a four-cylinder. If you need more power, add a turbo or two, or go V8. See you. 10 years ago, the motoring journalist Jason Kamisa, the guy that makes those amazing Hagerty videos now, actually interviewed BMW engineers asking why they've never developed a V6 engine. I found their answer incredibly interesting. Jason wrote in Road & Track, BMW engineers admit that they regularly develop and test prototype V6s per internal policy, but say the results don't come close to meeting company noise and harshness standards. Mercedes-Benz must not have such stringent benchmarks. That fascinates me, that BMW engineers just of a week develop a new engine layer just to see how it will get on, and a lot of them, especially V6s, fall short of the qualities and standards that their straight sixes get to. Just imagine all the different engine layers those guys have developed that will never see the light of day. Maybe V4s, inline fives, a new V10, we know that they developed a V16. I bet there's a shelf somewhere at BMW HQ in Munich that has the most unbelievable collection of engines, one-offs, that we will never get to see. Imagine how cool it would be to check those out. The ultimate BMW six-cylinder engine has to be the S54. To non-BMW engine nerds, that's the 3.2 found in the E46 M3. 24 valves, 360 horsepower, 273 pounds-feet, 8,000 RPM. Add in a carbon intake plenum and an exhaust, and you have one of the zingiest, rasping, pure motorsports straight sixes ever put in a production car. Now, I say BMW has never made a V6 engine. Well, I've heard a rumour that renders that void. I may get in trouble for this. BMW might not be very happy with me sharing it, but allegedly, they have developed a twin-turbo V6 that is found in the back of a car that I mentioned earlier in this video. Yes, that's right. The twin-turbo V6 found in the back of the McLaren Artura has apparently come from the amalgamation of two three-cylinder turbo engines from the BMW i8. The thing is, these days, it's quite hard to justify developing a brand new internal combustion engine. If you are a current manufacturer, you're either electrifying all your cars or you're waiting around for sustainable fuels or hydrogen combustion to become a thing. If that's the case, you've probably got the engine technology, by and large, already sitting around. When McLaren planned to downsize from their V8 twin-turbo to a V6 twin-turbo hybrid, they clearly looked at BMW and asked, can you guys do it for us? That makes a lot of sense. It's a lot simpler. By starting with the i8's engine, you've already got your combustion system and cylinder head architecture in place. Then it's a case of creating a new block, new crankcase, and crankshaft, and you're good to go. You've got yourself a twin-turbo V6. The i8's engine is a 1.5-litre three-cylinder turbo. Double it, and you get a three-litre twin-turbo McLaren V6. The person that I spoke to actually witnessed some of the engine development going on, and every shirt around the engine had a BMW badge on it. Now, I don't have any physical evidence to prove any of this. I imagine if I email McLaren about it, they'll tell me exactly where to go. Considering what I was told, it seems plausible. I love engine stories like this. If anyone out there watching this knows anything more about that twin-turbo V6, do let me know, or other similar engine stories. I want to know about it. DM me on Instagram, Mike underscore Fernie. Let's get nerdy. 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