Interesting Engine Technology
#16
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
i think the key is all these other ideas (electronic, hydraulic, whatever) use MORE parts, when the issue is with speed. in reality, cams, especially with solid lifters, are fairly directly connected to the valve. all this other stuff seems like it would add in more delay between the open signal being sent and the valve getting open. that's the idea of the rotary valve, only one part. i can see that the seals would be an issue though, as the constant scraping of the valve along the seal edge would wear it down. rotary engines do it though, on the apex seals, as do other engine parts like crank and rod bearings, so it seems like it should be possible.
#17
Hey Man
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
There have been patented rotary valve designs going back to the 20's. Coates has held the patent on his version of the rotary valve since 1990. I agree with Randy, the real world bugaboos of this system must exist or an automaker would have picked it up by now. The future of electro-hydraulic valves is probably the next wave. I may be wrong but didn't the Acura NSX experiment with an electro solenoid system back in their early racing development but settled on the VTEC due to heat problems?
#18
Race Director
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Originally Posted by patrat
The restandardization isnt for the sake of electronic valvetrains, they would just be a beneficiary. The reason for the change is that the current electronics suites (entertainment, navigation, climate control, etc) are reaching the limit of what a 12V automotive generator can supply, current wise.
#19
Addict
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
BMW bought the rights to an electromagnetic valve actuation system from Aura Systems in El Segundo late 1990’s, but I believe that the actuators ended up being too large and the power consumption was taxing the alternator too much.
As you may know they (BMW) now have mechanically actuated, fully controllable valves (open, close and lift) in their latest engines eliminating some pumping loss, by also serving the function of the traditional throttle body. I believe the 745Li was the first to arrive here with this technology.
The main challenge in designing electro-magnetic and electro-hydraulic valves is in creating soft seating under all conditions (engine vibration, overcoming combustion pressures at exhaust time, etc.).
Laust
As you may know they (BMW) now have mechanically actuated, fully controllable valves (open, close and lift) in their latest engines eliminating some pumping loss, by also serving the function of the traditional throttle body. I believe the 745Li was the first to arrive here with this technology.
The main challenge in designing electro-magnetic and electro-hydraulic valves is in creating soft seating under all conditions (engine vibration, overcoming combustion pressures at exhaust time, etc.).
Laust
#20
Race Director
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Originally Posted by yoyoguy2
i think the key is all these other ideas (electronic, hydraulic, whatever) use MORE parts, when the issue is with speed. in reality, cams, especially with solid lifters, are fairly directly connected to the valve.
#21
Race Director
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Yeah, I think valvetrain technology is evolving towards that. Lots of this kind of stuff have been tried in F1 racing for years. Another idea is using pneumatic springs to handle most of the mass of the valve, and having the solenoids apply the differential force needed to open & close it.
"And,bikes now have rev-limits of 17 000 + rpm as stock...even seen Nissan RB26DET 2.6-litre straight-6 engines doing 14 000 rpm,so it's not the poppet valves that's restricting them,at least. "
No, it's more of an issue of varying the valve-lift, timing and duration such that it's optimal at each RPM-range. Over 20-years ago, Honda came out with the NR series bikes in endurance racing with 8-valves per oval cylinder. The thing revved to 20,000 easily. The street version was de-tuned to about 16,500rpm or so.
"And,bikes now have rev-limits of 17 000 + rpm as stock...even seen Nissan RB26DET 2.6-litre straight-6 engines doing 14 000 rpm,so it's not the poppet valves that's restricting them,at least. "
No, it's more of an issue of varying the valve-lift, timing and duration such that it's optimal at each RPM-range. Over 20-years ago, Honda came out with the NR series bikes in endurance racing with 8-valves per oval cylinder. The thing revved to 20,000 easily. The street version was de-tuned to about 16,500rpm or so.
#22
Nordschleife Master
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
The company I work for makes test equipment for the auto industry, mong others. The 48V effort appears to have peaked and is subsiding without happening.
The purpose was to power the ever-increasing electronics in the car. At 48V there's less current needed for the same power (W=IV, donchano) The industry now thinks that there won't be more mechanical stuff added (what, no power vanity mirrors?) and that the computers and such that are constantly powered are reacting prepdictably to Moores Law and getting smaller and taking less power.
Now if they add personal video screens and massage chairs, then it may become a reality.
The installed base is fairly big for 12V batteries, chargers, testers, accessories and such. I'd bet it could be pioneered on high-end cars as a differentiator. "The new Lexus with four times the power."
Maybe someday...
Reminds me of the Wankel engine. A big buzz in the '60s for that. Now it's Mazda with, what, one car? Just hard to make it seal reliably and cheaply. Sorta like the rotary valve.
The purpose was to power the ever-increasing electronics in the car. At 48V there's less current needed for the same power (W=IV, donchano) The industry now thinks that there won't be more mechanical stuff added (what, no power vanity mirrors?) and that the computers and such that are constantly powered are reacting prepdictably to Moores Law and getting smaller and taking less power.
Now if they add personal video screens and massage chairs, then it may become a reality.
The installed base is fairly big for 12V batteries, chargers, testers, accessories and such. I'd bet it could be pioneered on high-end cars as a differentiator. "The new Lexus with four times the power."
Maybe someday...
Reminds me of the Wankel engine. A big buzz in the '60s for that. Now it's Mazda with, what, one car? Just hard to make it seal reliably and cheaply. Sorta like the rotary valve.
#24
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
![](http://www.coatesengine.com/images/graphics/product.jpg)
Rotary valves have been used extensivly in 2-stroke motors, other than the seal life issue I see this design as very effective the rotating/moving mass is way down compared to coventional vlaves. looks like a no-brainer to me, I bet we see this develop into something soon. Even if the seals only lasted a race or 2, with the small amount of parts involved it would be worth it for the performance gain!
#25
Three Wheelin'
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Even if the seals only lasted a race or 2, with the small amount of parts involved it would be worth it for the performance gain!
#26
Wax On, Wax Off
Rennlist Member
Rennlist Member
Join Date: May 2003
Location: 5280 ft above the sea
Posts: 17,727
Likes: 0
Received 3 Likes
on
3 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I had a friend suggest I put one of those on the 924S... He said that, and individual throttle bodies per cylinder would make a very noticable increase in power....
#27
Three Wheelin'
Join Date: Sep 2003
Location: Bremerton, WA
Posts: 1,750
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Originally Posted by Porschephile 924
I had a friend suggest I put one of those on the 924S... He said that, and individual throttle bodies per cylinder would make a very noticable increase in power....
![hiha](https://rennlist.com/forums/graemlins/roflmao.gif)
![Stick Out Tongue](https://rennlist.com/forums/images/smilies/tongue.gif)
#28
Wax On, Wax Off
Rennlist Member
Rennlist Member
Join Date: May 2003
Location: 5280 ft above the sea
Posts: 17,727
Likes: 0
Received 3 Likes
on
3 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Originally Posted by porschefig
and a very noticable decrease in your wallet
![Stick Out Tongue](https://rennlist.com/forums/images/smilies/tongue.gif)
![hiha](https://rennlist.com/forums/graemlins/roflmao.gif)
![Stick Out Tongue](https://rennlist.com/forums/images/smilies/tongue.gif)