Engine Brake Logic from Alan Falowski

[Diesel85]

This is very interesting for folks regarding the Cummins exhaust brake from Alan Falkowski (works for Stellantis):



See: 54:00 to 57:00

Interesting comments though from an engine engineer regarding engine braking.

What are folks thoughts on this? I always thought it was the turbo that does this...

 

[Timd32]

My take was he mentioned Jake Brakes and that's what he was saying adds too much complexity to the valvetrain.

Most gassers have some sort of dynamic hill decent that is drivetrain controlled not engine controlled.

It's been around for a long time, my 2019 Suburban has a decent system if you hit the brakes twice on a decend it triggers that mode of operation.

 

[AH64ID]

Alan not talking about the same engine that TFL is, our 6.7 Cummins. Alan is also talking about an engine brake, or compression release brake, and not an exhaust brake.

We have an exhaust brake that is producing exhaust back pressure thru the turbo variable geometry.

 

[Diesel85]

Alan not talking about the same engine that TFL is, our 6.7 Cummins. Alan is also talking about an engine brake, or compression release brake, and not an exhaust brake.

We have an exhaust brake that is producing exhaust back pressure thru the turbo variable geometry.

Alan was asked specifically about the Cummins 6.7l the turbo variable geometry. Alan said it's more than just the turbo. Which I thought was interesting is why I posted asking the question. Sorry, should've been clearer.

But yes, I agree, I thought it was just the exhaust back pressure thru the turbo variable geometry, not anything specific with the valve train.

 

[AH64ID]

Alan was asked specifically about the Cummins 6.7l the turbo variable geometry. Alan said it's more than just the turbo. Which I thought was interesting is why I posted asking the question. Sorry, should've been clearer.

But yes, I agree, I thought it was just the exhaust back pressure thru the turbo variable geometry, not anything specific with the valve train.

He was asked about it, but he didn’t answer about it at all. So either he didn’t hear the reference to the Ram HD or he’s not familiar with it and was referencing other engines. Either way what he talked about was not applicable to our 6.7L Rams.

 

[Diesel85]

He was asked about it, but he didn’t answer about it at all. So either he didn’t hear the reference to the Ram HD or he’s not familiar with it and was referencing other engines. Either way what he talked about was not applicable to our 6.7L Rams.

Maybe I misunderstood his response then. I re-watched it again, and it really sounds as if he's stating the valve train... but I agree that he's not familiar with it.

I went ahead and wanted to do a snippet of the transcript, and yep, I think he's just not familiar with how the diesels work: ...unless you do something like and you seen the Diesels right where they they add a a jake break to the the the valves but um so far I'm not aware of anybody that's gone to that measure with our gasoline engines and does it is it just a matter of the turbocharger design right because let's say the commons right the big heavy duty Rams uh with the cumin they have the exhaust brake feature um is it just of the turbocharger design itself no it's mechanism in the valve train itself that's doing that and assisting and so it's it's very intrusive you might say to the engine design and certainly for the big diesel engines that you know...