[Studebaker]

The Renault engine does not use desmotronic cam action to close the valves in their F1 engine. . The valves are of a conventional type and uses a nitrogen bag instead of a spring. The bag pressure is electronically controlled for increase pressure as RPM goes up. Think of it as a small round bag around the stem of a valve which is recessed in a hole in the head. Increasing the pressure in the bag is like increasing spring pressure but with no bounce off the seat at high RPM, nitrogen also aids in cooling. A small feed line increases or decreases pressure , this is computer controlled.

[4 Jaw Chuck]

I don't know guys, but heres my idea of the future.

Ceramic Rotary Engine Project

Once you have a 8500 rpm flame belching rotary under your hood that weighs 180 pds and puts out 275HP...you never want to go back.

Hence the Avatar.

Imagine it with a ceramic turbo putting in 30psi of boost...oh yea thats the stuff!

P.S. This one should be able to burn hydrogen with no modifications.

Daddy want!

[spinn]

i like wankle rotory type. the simplicity is cunning. however, i dont see many 80-90's rx-7 on the roads these days. i dont think its ready yet? mayybe im wrong.


the common trade in i see, is a honda i4 with 300k miles.

[oldbogie]

Originally Posted by spinn

i have been following the developement of springless heads. to me, stock spring type heads, the method is too antiquated. by now there is a better way. spring seat pressure can hold your car back , driving around, robbing your low end torque. could a springless head be a step in the correct(not neccesarily, right) direction?

pics coats type..


youtube video idling decuir head
http://www.youtube.com/watch?v=GXIdOTkJhEY

Obsolete, in the next couple years the concept of the mechanically operated valve train will be eliminated. In place will be electrically actuated valves controlled by the computer. The advantage is that cam timing can be varied with engine loading, throttle setting, and RPM. At idle, lift will be low and duration short, at WOT lift will be high and duration long. In between these points will be in-between durations and lifts. The timing points of valve opening and closing will be variable as will LSA, LCA and resultant overlap. The end product will be tremendously powerful engines that are as docile as a lamb at idle, get fantastic fuel economy with very reduced emissions.

This is in the lab as I write and is only "adequate durability" away from production.

Bogie

[spinn]

get crackin already.

[Rob Keller]

Originally Posted by spinn

get crackin already.

LOL!!!








R

[curtis73]

There is a 4 cylinder bike engine in use right now (I think) that uses two cams, one to open and the other to close. Instead of springs, the valve is actively closed by another cam lobe.

[4 Jaw Chuck]

Originally Posted by spinn

i like wankle rotory type. the simplicity is cunning. however, i dont see many 80-90's rx-7 on the roads these days. i dont think its ready yet? mayybe im wrong.


the common trade in i see, is a honda i4 with 300k miles.

I had 275 000 miles on my 12A in a 1981 RX7...until I cracked an apex seal at the track. Bad float in the Holley 650 DP dumped raw fuel from the vent tube during a race (I kept going!) which caused raw fuel to pour from the exhaust during the last 6 laps. Amazingly it ran fine for a few more hours but I guess the seal quenching in flood conditions made it crack.

It still ran on two seals, although it was like a V6 with two cylinders missing. I drove it like that for two more months until I could procure another block for $200.

Not too many engines that will still run strong even with raw fuel from a Holley red pump at full tilt pouring into it. Actually during the race I didn't even notice until when I pulled into the pits and the other guys pointed out the line of gasoline around the track, they didn't even black flag me ha-ha!

The reason why you don't see many ones used is because people run them out of oil, they draw motor oil from the crankcase for the injection. I ran mine on premix but every one I see in the junkyard was run out of oil.

Too bad that keeping oil in a vehicle is so difficult for most people.

Mmmmm...but a ceramic rotary without a cooling system and using gold running surfaces with no injection oil is my idea of fun, make the shortblock $100 to replace and I'll buy at least two!