Video on difference between V6 and straight six engines

[paulri]

I just saw this on youtube: https://www.youtube.com/watch?v=u3XSfVPFM74 I really liked how simple it was for a non-mechanic like myself. Is this accurate? Any points that he might have left out, in the pros/cons?

 

[Kira]

Accurate, yes. Wanna show 'em how smart you really are???....get a 4. Volvo made their 5 cylinder engines since the '80's with great success. They made 2.0, 2.3, 2.4, 2.5 liter versions in both turbocharged and normally aspirated variants. 2007 was the last year Volvo offered the 5 cylinder. Volvo also made 4 cylinder engines using the same design. I suppose they still make a 4.

 

[DeepFriar]

No, not as accurate as it could be. The lack of discussion of 60 degree versus 90 degree inclined V6's leaves a viewer beliving that all V-6's need balance shafts. They don't. Further, some mention of why there are 90 degree engines in stead of 60 degree ones (primarily the availability of 90 degree V8 tooling) might have shown a more indepth knowledge on the part of the author. Good example of the reason that second order imbalances are mitigated in straight 6's though.

 

[PimTac]

What? No mention of the slant six?

 

[Quattro Pete]

Originally Posted by Kira

Volvo made their 5 cylinder engines since the '80's with great success. They made 2.0, 2.3, 2.4, 2.5 liter versions in both turbocharged and normally aspirated variants. 2007 was the last year Volvo offered the 5 cylinder.

The straight five was offered in some Volvo applications up until 2016.

 

[meep]

I do like the volvo 5s but they certainly have NVH tendencies which 4s do not, resulting in softer mounts to compensate - which is fine as long as you aren't deftly into performance. Volvo 5s with stiff mounts, from what I've read (and can believe) are not fun to live with as a DD. The power/torque curves I found ideal - more torque than a 4 but without the added size of a 6.

 

[maxdustington]

Originally Posted by Kira

Accurate, yes. Wanna show 'em how smart you really are???....get a 4. Volvo made their 5 cylinder engines since the '80's with great success. They made 2.0, 2.3, 2.4, 2.5 liter versions in both turbocharged and normally aspirated variants. 2007 was the last year Volvo offered the 5 cylinder. Volvo also made 4 cylinder engines using the same design. I suppose they still make a 4.

Still not as cool as a VR5

 

[Cujet]

Audi made a racing diesel 120 degree V6 with a hot-V configuration (exhaust ports on top) Quote WIki: "120° could be thought of as the natural angle for a V6. Each cylinder fires a power stroke every 120° of crankshaft rotation. This allows pairs of pistons to share crank pins (a connection on the crankshaft). Unlike the V8, there is no way to arrange a V6 to balance the piston forces. Because of the odd number of cylinders in each bank, a balance shaft is needed."

 

[edyvw]

Originally Posted by paulri

I just saw this on youtube: https://www.youtube.com/watch?v=u3XSfVPFM74 I really liked how simple it was for a non-mechanic like myself. Is this accurate? Any points that he might have left out, in the pros/cons?

So, so. It does not mention VR6 from VW, which currently has 10.6 degrees angle, one head. It states: it makes inline 6 all but dead, then at the end says it is making come back. V6 is cheap solution to more power. It allows you to use on multiple platforms, in both longitudinal applications (Lexus) and transverse applications (Toyota). So, it makes sense for manufacturers like that, it does not make sense for manufacturers like BMW that built name on inline 6 engines. But, modularity between 4cyl and 6cyl means inline six will probably be engine design of choice for luxury brands bcs they will all have forced induction in order to meet emission standards, which means both 3, 4 and 6 cyl (like BMW) could be made on same line. Mercedes is bringing back I6 after 20 years, and FCA is also introducing I6, and apparently Mazda too.

 

[hatt]

Inline 6 = Beauty and elegance. V6 =

 

[d00df00d]

Originally Posted by paulri

I just saw this on youtube: https://www.youtube.com/watch?v=u3XSfVPFM74 I really liked how simple it was for a non-mechanic like myself. Is this accurate? Any points that he might have left out, in the pros/cons?

It's good enough. These days, either engine type can be made to be as smooth and/or powerful as it needs to be. Lighter internals go a long way toward mitigating vibration. I guess if you're really trying to push the limits of smoothness, you'd still prefer an inline-6, but I have a hard time imagining an application like that. It's more common to see applications where all you care about are power and compactness, and in those cases a V6 is a great call (e.g. Nissan GT-R, Ford GT, Acura NSX). AFAIK, the main reasons to recommend one configuration over the other are packaging and development cost. Mercedes-Benz recently said they'll be phasing inline-6s back in, partly because they're producing a ton of inline-4s and it's super easy for them to derive an inline-6 by just tacking on 2 more cylinders. BMW has been all about inline-6s for a long time and has basically zero invested in V6s, so it makes sense for them to stick with inlines. On the other hand, if you're Hyundai, Nissan, or Honda, you're already make a ton of V6s to fit into FWD economy cars, so you probably won't be tempted to make an inline-6 even if you design a car that could be made to accommodate it (e.g. Genesis, GT-R). Audi is in a similar boat because it draws so heavily from the VW parts bin.

 

[hatt]

I can't believe Toyota punted on the new Supra engine and used BMW.

 

[edyvw]

Originally Posted by hatt

I can't believe Toyota punted on the new Supra engine and used BMW.

Why?

 

[edyvw]

Originally Posted by d00df00d

Originally Posted by paulri

I just saw this on youtube: https://www.youtube.com/watch?v=u3XSfVPFM74 I really liked how simple it was for a non-mechanic like myself. Is this accurate? Any points that he might have left out, in the pros/cons?

It's good enough. These days, either engine type can be made to be as smooth and/or powerful as it needs to be. Lighter internals go a long way toward mitigating vibration. I guess if you're really trying to push the limits of smoothness, you'd still prefer an inline-6, but I have a hard time imagining an application like that. It's more common to see applications where all you care about are power and compactness, and in those cases a V6 is a great call (e.g. Nissan GT-R, Ford GT, Acura NSX). AFAIK, the main reasons to recommend one configuration over the other are packaging and development cost. Mercedes-Benz recently said they'll be phasing inline-6s back in, partly because they're producing a ton of inline-4s and it's super easy for them to derive an inline-6 by just tacking on 2 more cylinders. BMW has been all about inline-6s for a long time and has basically zero invested in V6s, so it makes sense for them to stick with inlines. On the other hand, if you're Hyundai, Nissan, or Honda, you're already make a ton of V6s to fit into FWD economy cars, so you probably won't be tempted to make an inline-6 even if you design a car that could be made to accommodate it (e.g. Genesis, GT-R). Audi is in a similar boat because it draws so heavily from the VW parts bin.

Actually Audi has V6, VW has VR6 engines. And it will stay that way. VW decided to separate Audi, Porsche, Lamborghini, Bentley as much as possible from VW, SKoda, SEAT. That is why VW just introduced new 2.5 and 3.0 VR6 turbo engines, at the same time when Audi and Porsche got 2.9 V6 engines. Those VR6 and V6 do not have anything in common except, maybe turbo charger.

 

[hatt]

Originally Posted by edyvw

Originally Posted by hatt

I can't believe Toyota punted on the new Supra engine and used BMW.

Why?

Because Toyota builds better engines?

 

[edyvw]

Originally Posted by hatt

Originally Posted by edyvw

Originally Posted by hatt

I can't believe Toyota punted on the new Supra engine and used BMW.

Why?

Because Toyota builds better engines?

LOL. Is that why they are buying diesel engines from BMW?

 

[Skippy722]

Originally Posted by hatt

Originally Posted by edyvw

Originally Posted by hatt

I can't believe Toyota punted on the new Supra engine and used BMW.

Why?

Because Toyota builds better engines?

Toyota isn't going to spend millions or more developing, testing, and certifying an engine for 1 vehicle.

 

[hatt]

Originally Posted by edyvw

Originally Posted by hatt

Originally Posted by edyvw

Originally Posted by hatt

I can't believe Toyota punted on the new Supra engine and used BMW.

Why?

Because Toyota builds better engines?

LOL. Is that why they are buying diesel engines from BMW?

So you're saying BMW builds better engines? Or that Toyota is trying to save a couple bucks on limited market items?

 

[hatt]

Originally Posted by Skippy722

Toyota isn't going to spend millions or more developing, testing, and certifying an engine for 1 vehicle.

It would have been cheaper. The warranty costs are going to eat them up. I don't know anyone with a BMW that doesn't have a great relationship with the BMW service shop and loaner car department. They always offload the thing before the warranty expires too.

 

[Skippy722]

Originally Posted by hatt

Originally Posted by Skippy722

Toyota isn't going to spend millions or more developing, testing, and certifying an engine for 1 vehicle.

It would have been cheaper. The warranty costs are going to eat them up. I don't know anyone with a BMW that doesn't have a great relationship with the BMW service shop and loaner car department. They always offload the thing before the warranty expires too.

No, it really wouldn't have. Molds to cast engine blocks alone can easily reach a million. Then you have machining time on top of that, which isn't cheap, considering they likely have no way or room on their current lines to accommodate a straight 6. Then once you finally have a working prototype, you have to test and tweak it, again time intensive and not cheap. Only then can you certify and test for emissions compliance. For a low production sports car, it makes absolutely no sense spending all that money to develop an engine when someone else already has. The B58 engine has only been out for 4 years, and is a massively different than the previous trouble prone N54/N55 engines. You can't fairly compare them on a reliability standpoint.