new benz

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Was just reading about the new Benz sportscar and noted that it can inject fuel at up to 5 times per CE and spark the plug up to 100 times!

I've seen diesels such as the VM Motori V6 used in the Dodge Ram that can inject up to 8 times per CE.

The pace of technology is amazing...
 
Yes it is. Similar to the pace in F1 engines and hybrid power systems. Next is the cam less valve train, that will change the internal combustion engine as we know it.
 
Camless valvetrains have been worked on since the mid-70's (that I know of). Either electric or hydaulic actuation systems have been considered, but they never really deliver on the promise of incredible fuel economy. Too much parasitic loss for the pumping work benefit that you get. And a lot of technical risk, too. If the engine loses sync once in its life, and the ECU opens valves at the wrong time, it's a major failure. But the list of different operating modes that could be done with camless is mind-boggling.
 
A_Harman, at least with a cam, there's a recovery of (a very small) amount of energy that reduces the energy input of the valves that are being opened at the same time...

I remember a lecturer talking about control and damping on closing, and I suggested that dissipation of energy as heat was wasteful compared to getting it back mechanically.
 
Originally Posted By: rodinator1234
Yes it is. Similar to the pace in F1 engines and hybrid power systems. Next is the cam less valve train, that will change the internal combustion engine as we know it.

I was just reading up on camless engines. Cool technology. More power and better fuel economy.
 
Originally Posted By: rodinator1234
Next is the cam less valve train, that will change the internal combustion engine as we know it.


Originally Posted By: A_Harman
Camless valvetrains have been worked on since the mid-70's (that I know of). Either electric or hydaulic actuation systems have been considered, but they never really deliver on the promise of incredible fuel economy.


It's already a reality, and has been for a number of years. Just not in automotive engines.

The Wärtsila (Sulzer) RT-Flex engines use a common-rail hydraulic system with electronically-controlled valve actuation - there is no camshaft. These are amongst the most thermally efficient engines there are. Of course, the task is made easier by the very slow operating speed, plus the fact there is only one valve per cylinder.
 
Originally Posted By: A_Harman
Camless valvetrains have been worked on since the mid-70's (that I know of). Either electric or hydaulic actuation systems have been considered, but they never really deliver on the promise of incredible fuel economy. Too much parasitic loss for the pumping work benefit that you get. And a lot of technical risk, too. If the engine loses sync once in its life, and the ECU opens valves at the wrong time, it's a major failure. But the list of different operating modes that could be done with camless is mind-boggling.



Which is why systems like MultiAir are so successful. The cam is retained, but it only defines the "outer envelope" of the valve profile, so to speak. Within that envelope, clever hydraulics allow infinite lift and duration variability. Its still all powered by the cam, the hydraulics are able to rapidly capture and release valve lifting energy from the cam as needed.
 
Sounds like Ben is using solenoid injectors for their gas engines.

Piezo go 7x.

BMW used piezo for N54 and went to solenoid on the N55 and newer gas engines.
 
Originally Posted By: SteveSRT8
The pace of technology is amazing...


Plenty o' really smart folks in this business.

I hope SteveSRT8 will get that M-B and flog it during his track days!
 
Originally Posted By: splinter
Originally Posted By: SteveSRT8
The pace of technology is amazing...


Plenty o' really smart folks in this business.

I hope SteveSRT8 will get that M-B and flog it during his track days!


Sure hope so. It's a heck of a car. Even if I don't get one, one of my wealthy track rat friends will, and I'll get some seat time!
 
Well Mercedes is usually a decade or so ahead, they are one of the best engine and transmission builders in the world.

They are also the largest producer of V12's in the world.

Which motor are you talking about, the one in the new AMG GT? I really like AMG's engineering effort with Pagani, its really amazing all the power they screwed out of the old M120 V12.
 
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