The renaissance of the Inline 6

[Galaxy]

What's holding it back? I've been reading about solenoid-driven valvetrains for what seems like decades now, but nobody's managed to bring a design to market.

Fiat uses a cam less design on the intake valves of their Multiair engine family. On the exhaust side they apparently are having problems preventing the solenoids from being cooked. Only I4s. Would be neat to see that put on Chrysler engines. Koenigsegg has a valveless engine.

You mean 2-strokes?

No, a four stroke operated with electric (or electromagnetic, or some other form) valves.

[12,000 RPM]

Who has run a hot V configuration outside of '70s Formula One cars and mid engine Ferraris?

All the current German V8s are TT hot Vs. I think they all use the heads and probably pistons/con rods from their ubiquitous 2.0T 4 poppers.

I think we have crossed the event horizon of dieselly 500cc/cylinder turbo DI gas engines. Kinda sucks

[shp4man]

I don't want to go all retro on you guys, but the inline 6 is regarded as possibly the most dependable engines of all time. Why, you ask? Because it's easy to work on, no hidden, buried in parts removal problems issues. Chevrolet and other manufacturers used it for years for that reason.
Think of the reputation of the Chrysler slant 6, still talked about today, and the GM and Ford I6's. Now, add modern technology and metallurgy to these legendary engines. It's a win-win.

In case you haven't googled it, 153624 is the firing order for all inline 6's.

And yes, they can make power, if that's what the design specification calls for.   

[GoCougs]

What's holding it back? I've been reading about solenoid-driven valvetrains for what seems like decades now, but nobody's managed to bring a design to market.

My first guess is cost/benefit ratio. What with CVTs and 8-10 sp ATs the norm, engines don't need a wide powerband anymore.

[Eye of the Tiger]

My first guess is cost/benefit ratio. What with CVTs and 8-10 sp ATs the norm, engines don't need a wide powerband anymore.

Diesel time.

[12,000 RPM]

I don't want to go all retro on you guys, but the inline 6 is regarded as possibly the most dependable engines of all time. Why, you ask? Because it's easy to work on, no hidden, buried in parts removal problems issues. Chevrolet and other manufacturers used it for years for that reason.
Think of the reputation of the Chrysler slant 6, still talked about today, and the GM and Ford I6's. Now, add modern technology and metallurgy to these legendary engines. It's a win-win.

In case you haven't googled it, 153624 is the firing order for all inline 6's.

And yes, they can make power, if that's what the design specification calls for.

I don't think anyone is questioning the I6's advantages. Just sucks that we are losing choice. In time the only non-exotic engines available will be turbo I4s or I6s.

[Laconian]

Fiat uses a cam less design on the intake valves of their Multiair engine family. On the exhaust side they apparently are having problems preventing the solenoids from being cooked. Only I4s. Would be neat to see that put on Chrysler engines. Koenigsegg has a valveless engine.

My understanding is that MultiAir still uses cams, but the lobes push poppets which can be hydraulically disengaged by solenoids which are physically separate from the combustion chamber.

I used to be more excited about MultiAir, but it seems to be rather underwhelming in practice.

[Soup DeVille]

L Current BMW, M-B and Audi turbo V8s, Audi's 2.9L V6, upcoming Cadillac turbo V8, and probably others, are all "hot V."

I see.

That is not what that term used to mean. (when it applied to NA racing engines)

[FoMoJo]

Although with tech like a cam less engine one could simplify that. I am actually surprised that cam less tech is not taking off.

What's holding it back? I've been reading about solenoid-driven valvetrains for what seems like decades now, but nobody's managed to bring a design to market.

Koennigsegg, I believe, has the best solution...

https://www.youtube.com/watch?v=OZWeNPi2XkE

[AutobahnSHO]

looks expensive.

[GoCougs]

I see.

That is not what that term used to mean. (when it applied to NA racing engines)

What's the difference? As a casual observer it looks identical to me - exhaust on the inside of the V.

[GoCougs]

Koennigsegg, I believe, has the best solution...

https://www.youtube.com/watch?v=OZWeNPi2XkE

My second guess is it is very expensive/difficult to make reliable/durable over the long haul.

Each valve is actuated by an extremely precise, high bandwidth, and relatively powerful (i.e., current consuming/heat producing) actuator and requires a fair amount of processing power.

[FoMoJo]

My second guess is it is very expensive/difficult to make reliable/durable over the long haul.

Each valve is actuated by an extremely precise, high bandwidth, and relatively powerful (i.e., current consuming/heat producing) actuator and requires a fair amount of processing power.

We should see how it all works out in the not too distance future...Koenigsegg's Next Supercar Will Have a Camless Engine.

[Galaxy]

I see.

That is not what that term used to mean. (when it applied to NA racing engines)

What does it mean then? I always assumed hot V means that essentially the engine runs in reverse, with the exhaust in the center, and the intake outside.

[Galaxy]

My understanding is that MultiAir still uses cams, but the lobes push poppets which can be hydraulically disengaged by solenoids which are physically separate from the combustion chamber.

I used to be more excited about MultiAir, but it seems to be rather underwhelming in practice.

You are right, I was under the impression that it works without a cam, and yes it is disappointing that the Fiat engines do not seem to have any fuel economy benefits.

Just learned that the Jaguar/Land Rover Ingenium engine family (including the new I6) uses the Fiat system.

[MX793]

What is the advantage?  The 6 is longer.

Plumbing for the turbo is cleaner on an I6 than V, and takes up less space, width-wise, than a V6.

[Soup DeVille]

What does it mean then? I always assumed hot V means that essentially the engine runs in reverse, with the exhaust in the center, and the intake outside.

Never seen it applied to turbos, that's all. In retrospect, that's probably not a definitive difference.

[12,000 RPM]

Usually the simplest solutions work best, which is why Toyota is often tops in fuel economy and reliability.

[FoMoJo]

Usually the simplest solutions work best, which is why Toyota is often tops in fuel economy and reliability.

By using and BMW engine...

[giant_mtb]

153624?  I thought it was 25 or 6 to 4?

[93JC]

142635

[Galaxy]

Add Mazda to the companies that are going to Inline 6. Both diesel and gasoline.

[Xer0]

Oh god, really?  When was this announced?  And if the SkyactiveX and the diesel are any indication, it will not meet any deadlines or promises.

[Galaxy]

Oh god, really?  When was this announced?  And if the SkyactiveX and the diesel are any indication, it will not meet any deadlines or promises.

https://www.mazda.com/globalassets/en/assets/investors/library/presentation/files/pre190509_e.pdf

Page 25. I believe that this is the first mention, with no formal announcement, so it may have been leaked unintentionally.

[r0tor]

I would be pretty excited about a I6 turbo in a Mazda with a longitudinal layout

[12,000 RPM]

I would be pretty excited about a I6 turbo in a Mazda with a longitudinal layout

You and all the other actual buyers of this thing could probably fit in one (1) of said vehicles

Like Xer0 said, diesel, Skyactiv-X and now this... Mazda needs to focus on what makes sense, including leveraging its partnership with Toyota, who has great hybrid tech, a brand new RWD platform and a brand new turbo 6 popper to go with it

This rumor has Alpha platform vibes

[r0tor]

You are right, I was under the impression that it works without a cam, and yes it is disappointing that the Fiat engines do not seem to have any fuel economy benefits.

Just learned that the Jaguar/Land Rover Ingenium engine family (including the new I6) uses the Fiat system.

Actually the Giulia 2.0T is about the best in class for fuel efficiency and power output (among the 4 cylinders).   Multiair is rather simplistic and effective.

[r0tor]

You and all the other actual buyers of this thing could probably fit in one (1) of said vehicles

Like Xer0 said, diesel, Skyactiv-X and now this... Mazda needs to focus on what makes sense, including leveraging its partnership with Toyota, who has great hybrid tech, a brand new RWD platform and a brand new turbo 6 popper to go with it

This rumor has Alpha platform vibes

Mazda has run out of growth potential with generic 4 fwd 4 cylinders

[Payman]

Mazda needs to do a sportscar with the Skyactiv 6. Maybe partner with Alfa. Offer a stick and make it $10k cheaper than the Supra. 

[r0tor]

I wonder if Mazda would just use the Giulia platform for a rwd platform