CarSPIN Forums

Auto Talk => General Automotive => Topic started by: Laconian on August 12, 2018, 05:41:14 PM

Title: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: Laconian on August 12, 2018, 05:41:14 PM
https://newatlas.com/camcon-digital-iva-valve-system/55827/

High bandwidth valvetrain control, lots of intriguing possibilities...
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: CaminoRacer on August 12, 2018, 06:29:39 PM
Guess they haven't heard of FreeValve.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: 12,000 RPM on August 12, 2018, 06:48:46 PM
Lots of ways to slice it. I'm still bullish on electrification. Expensive, but relatively simple and reliable. Will be cool if they actually implement this though.

I'm also very intrigued by the opposed piston 2 strokes....
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: Galaxy on August 12, 2018, 11:00:42 PM
Quote from: CaminoRacer on August 12, 2018, 06:29:39 PM
Guess they haven't heard of FreeValve.

They updated the article at the end because of FreeValve.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: CaminoRacer on August 12, 2018, 11:11:11 PM
Quote from: Galaxy on August 12, 2018, 11:00:42 PM
They updated the article at the end because of FreeValve.

Ah, I see.

I suppose this new system does allow more freedom, since you can install a very high lift, high duration cam and then only go part of the way up for low-rpm cruising, then return back down the lobe instead of cresting it.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: Laconian on August 12, 2018, 11:15:28 PM
I thought MultiAir engines could deliver some of these great things, but aren't those engines all turds?
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: giant_mtb on August 12, 2018, 11:27:39 PM
Powervalves on everything.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: Galaxy on August 13, 2018, 12:19:15 AM
Quote from: Laconian on August 12, 2018, 11:15:28 PM
I thought MultiAir engines could deliver some of these great things, but aren't those engines all turds?

I wondered about that as well. I guess deficiencies in other areas of the engine counteract the advanced engine control potential of multiair. Plus Multiair is a hydraulic system, that adds a lot of problems.

Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: MX793 on August 13, 2018, 05:07:00 AM
Quote from: Laconian on August 12, 2018, 11:15:28 PM
I thought MultiAir engines could deliver some of these great things, but aren't those engines all turds?

Fancy heads on 25-30 year old engine designs (FIRES engine that Fiat uses came out in 1985).  Plus, the Italians don't have a great reputation for robust, complicated designs.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: 12,000 RPM on August 13, 2018, 05:35:46 AM
I love N/A engines but as far as efficiency goes I'm feeling like the biggest ROIs are in recapturing waste energy.... be it from the exhaust or the brakes. Character is always going to come at the expense of efficiency.... if these heads allow high revving, the rest of the engine will have to be designed around that and be less efficient overall. And I think people who prioritize engine character *generally* don't care about fuel economy.

So for my money I'd rather have the investments and focus be made in recapturing waste heat. Out of the losses pie that's where the bulk of the pain is. Plus there are huge gains to be made just in overall engine design. Look at Toyota's new 2.0L:

https://newsroom.toyota.co.jp/en/powertrain2018/engine/

It's a regular old NA engine. But through a holistic focus on efficiency and simplicity they've achieved record high thermal efficiencies in engines going into ~$20K cars. Imagine that focus integrated with an electric turbo and regenerative braking. All of a sudden fancy valvetrains become a bit expensive. Which is why I think automakers have pulled away from them.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: r0tor on August 13, 2018, 06:18:15 AM
Quote from: Laconian on August 12, 2018, 11:15:28 PM
I thought MultiAir engines could deliver some of these great things, but aren't those engines all turds?

The multiair 2 in the alfa giulia/stelvio is pretty stout... Capable of ~350hp and 35 mpg with a tune
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: MrH on August 13, 2018, 07:05:07 AM
Quote from: Laconian on August 12, 2018, 11:15:28 PM
I thought MultiAir engines could deliver some of these great things, but aren't those engines all turds?

Yes.  Yes they are.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: GoCougs on August 13, 2018, 08:50:51 AM
Quote from: CaminoRacer on August 12, 2018, 06:29:39 PM
Guess they haven't heard of FreeValve.

FreeValve uses air and the like; this is purely electromechanical.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: FoMoJo on August 13, 2018, 09:53:59 AM
Quote from: CaminoRacer on August 12, 2018, 06:29:39 PM
Guess they haven't heard of FreeValve.
Does Koenigsegg's system have the ability to limit the opening of the valves?  Haven't kept up with it lately.
Title: Re: "12 stroke", 2 stroke on demand, HCCI, etc. - the Digital Engine
Post by: 12,000 RPM on August 14, 2018, 05:06:16 AM
Koenigsegg has full control of the valves