I was fliping through SAE Automotive Engineers Magazine and I saw a small artical on Lotus's development of fully exlecto-hydrolic valves. Valves that are %100 controlled by computer command. No cam, no rods, no valve springs, no rockers... just a fully computer control valve where lift and duration are controlled with electrons! They seemed to have huge success with compression ignition engines in cutting emmisions. Just imagine can be controlled to the smallest of tolerances over the entire RPM range... Looks like they are going to be seen starting in 2008. Wonder when they will end up in our Cummins? Time will tell.

Horace

 

Hey Horace,

Yes the camless has ben under development for quite some time. John Deere currently has some running prototypes in Diesel. Other majors do as well.

Its part of the reason the new higher voltage systems are being developed as well. 42 volts will soon be the standard to help run all the solenoids these engines will have.

Very cool to see you looking through the SAE docs...thumbs up Man.

Don~

 

Electronic valves are in use in Formula One. How else would those engines turn 15,000+rpms!

MikeyB

 

Yes, F1 has used them. 8)

The latest offering from BMW is a 2.2 litre engine that spins at 18,000 rpm. The stroke is less than 2 inches

Basically the piston just vibrates. ;D

Good enough for over 900 HP. No real figures given of course...but that is close.

Anyone wonder how they make the flame front keep up with the ultra fast piston travel? A good guess would be to remember that the fuel they run is not like the stuff we get at Chevron or Texaco. LOL!!

Don~

 

The artical also talked about how they are close to having cost low enough to make a production unit for the everyday vehicle. It did say that Lotus had signed one contract with a large auto maker to start putting them in a production vehicle in 2008.

 

Ohh, This could really be used to help spool up the turbos. Especially on the bottom end. Now we wouldn't have to worry about a cam designed to operate between 1,800 and 2,800 or 2,200 to 3,200. As long as the actuators could keep up, you could operate from 500, to 5,000.

Would it be worthwhile to make the exhaust valves hang open alot longer? I think this would help spool the turbo, along with lots of overlap when running high RPM, high Boost. With Enough overlap you could lower your Compression Ratio? So you could idle with a 19:1 C/R and at 3,500RPM run a 12:1 ?

Sounds possible.

Merrick