|
||||||||||
|
||||||||||
3 Aug 2005, 07:08 (Ref:1370774) | #26 | |||
Veteran
Join Date: Oct 2002
Posts: 1,618
|
Quote:
|
|||
__________________
I refuse to let fact get in the way of my opinion |
3 Aug 2005, 12:23 (Ref:1371039) | #27 | |
Veteran
Join Date: Jul 2005
Posts: 1,981
|
Positive closing of the valve by the camshaft (desmodromic valve operation) was first used in F1 by Renault, I believe, in their Turbo cars. Then it was done mechanically and the had a very small spring, like you would find on a washing line peg, that held the valve closed. This made for easier starting as, with any cam operated system, there has to be clearance between the valve and the operating mechanism to allow for thermal expansion of the components. This would leave the valve partly open when the engine is not running, even with mechanical closing.
I can see that with pneumatic operation this problem might disappear, but it is likely that some engines are desiged with such a spring to prevent disasterous valve/piston contact and to give decent compression when starting, although turning on the gas bottle prior to starting would, I imagine, have the same effect. |
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
n00b question about the rotary engine | Mike_Wooshy | Racing Technology | 6 | 3 Oct 2004 23:23 |
Engine Revs | Edmonton | Formula One | 8 | 9 Jun 2003 08:52 |
Set up info for rotary italsystem engine required | williamsf1 | Kart Racing | 7 | 19 May 2003 14:43 |
Rotary Engine | woodyracing | Racing Technology | 29 | 18 Dec 2002 09:05 |
****el Rotary Engine | floid2000 | ChampCar World Series | 7 | 10 Aug 2001 05:53 |