2014 Ford Transit to have 3.2 liter Diesel Powerstroke and Ecoboost

[Renze]

Obviously an engine with more and smaller pistons will seem smoother but mostly due to smaller explosions and better manufacturer design. You obviously didn't read everything I said as I explained that.

You linked engine smoothness to the number of explosions, and that an inline 5 has worse balance than an inline 4 because it overlaps explosions. thats BS, the inline 5 has some vibrations because the pistons arent allways opposed as in a 4, E.G. cylinder 1 and 4 going down when cylinder 2 and 3 are going up. It has to do with the weight of the crank, conrod and pistons and how that weight shifts during an engine revolution. Not with the number of firings, or if they overlap or not.

By the way, 5 cylinder engines need counter balancing weights as well.

They dont NEED them, neither do inline 4's NEED them. Just bigger inline 4's (over 2 liter usually) have double balancer shafts (because of increased engine component weight, and because these engines are used in higher end cars than a 1.4 liter economy, so there is more money to be spent on NVH reduction) where most 5's have a single balancer shaft. When the 4 and 5 pot are compared without balancer shafts, the inline 5 is smoother. When both engines have balancer shafts, the inline 5 is still smoother.

 

[Dmace]

It has to do with the weight of the crank, conrod and pistons and how that weight shifts during an engine revolution. Not with the number of firings, or if they overlap or not.

Ha! Speaking of BS.
So the weight is a factor in engine smoothness but power stroke overlap has no effect?
The firing overlap is what causes vibration in the first order, the second factor is end-to-end vibration from an odd number of cylinders firing, there's always more force on one half of the crankshaft than the other which not only causes greater vibration but also greater stress on the crankshaft and center bearings.

Plain and simple, there's plenty of reasons why 5 cylinder engines are rare and NVH is certainly one of them.

 

[aczlan]

Plain and simple, there's plenty of reasons why 5 cylinder engines are rare and NVH is certainly one of them.

Rare? A 5 cylinder engine has been the standard engine in FWD Volvos (850, S70, V70, S60, S80, S40, V40, XC90, etc) from 1993 to present. See the B5204, B5234, B5244, B5252, B5254 engines and their variants.

Aaron Z

 

[Dmace]

Yup rare!
Volvo's are not nearly as popular here as they are on your side of the pond.

There's probably 10 inline 4's for every 1 inline 5 cylinder Volvo. : laughing:

 

[94BULLITT]

Didn't Saab use 5 cylinders?

 

[aczlan]

Yup rare!
Volvo's are not nearly as popular here as they are on your side of the pond.
There's probably 10 inline 4's for every 1 inline 5 cylinder Volvo. : laughing:

My side of the pond? Might want to re-check where I am from :laughing:. Per google maps, its around 7 hours from where you are.
Are they as common as some other makes? No, but I see 10-20 of them each week in the 200-300 miles I drive.

Aaron Z

 

[Dmace]

My side of the pond? Might want to re-check where I am from :laughing:. Per google maps, its around 7 hours from where you are

Ha! As soon as I saw the Volvo reference I assumed it was Renze from Holland. No avatar pics on the cell phone app.

Still, they can still be referred to as rare when compared to 4 and 6 cylinders here.

 

[aczlan]

Ha! As soon as I saw the Volvo reference I assumed it was Renze from Holland. No avatar pics on the cell phone app.

I suspected as much , IIRC, his has a 5 cylinder Diesel (which I would buy in a heartbeat if it became available here). Just remember that there are many Volvo nuts here in the US... See TurboBricks | High Performance Volvo Club, Swedespeed.com, The Volvo Resource: brickboard.com, http://www.matthewsvolvosite.com/ and SwedishBricks Home Page

Still, they can still be referred to as rare when compared to 4 and 6 cylinders here.

I would say uncommon rather than rare, but I agree that 4 and 6 cylinder engines are far more prevalent in mainstream cars.

Aaron Z

 

[crazyal]

Volvos were extremely popular around here for quite some time. The Volvo wagon was the go to car for soccer moms. Now they aren't as popular but you still see them. The problem with the i-5 is that it's more expensive to build. It's not just the engine but the car needs more room under the hood too. I can't remember which company, maybe Honda had an i-5 with slightly offset cylinders to shorten the block but I don't think it ever made it in production. Kind of like the oval piston engines, nice concept but if you can't build them cheaply then it's not a real option.

 

[Renze]

Ha! Speaking of BS.
So the weight is a factor in engine smoothness but power stroke overlap has no effect?

I didnt say that. To be precise, your reaction

In engine design, the odd cylinder configurations are not as smooth primarily because of firing overlap.

is the B.S. i was pointing out. An increase of the number of cylinders, will allways lead to a smoother engine, no matter if odd or even. A four cylinder has far worse balance than a five, thats why most +2l engines these days have balancer shafts. Many inline 5's have a balancer shaft too, because they are higher end motors, not economy 4's. And balancer shafts dont make an inline 4 vibration free either...

Plain and simple, there's plenty of reasons why 5 cylinder engines are rare and NVH is certainly one of them.

Volvo 850/S70/V70 untill today have them, Audi has them, Volkswagen has them, Mercedes had them since 1974 untill the late 90's, Deutz Fiat and Same had industrial inline 5 diesels, Fiat automotive has inline 5 diesels, Scania has a 9 liter inline 5 truck engine.

Why do you still see inline 5's in automotive, and not anymore in industry ? In automotive, engine length is important in FWD cars with transverse engine, so an inline 5 is chosen as it runs smoother than a four cylinder, but can be built shorter than an inline six of the same cylinder volume.
In industry, NVH isnt as important so when a small envelope is needed you get a highly turbocharged 4 and if you need transient load response you get the 6.