formula 1 idle?

1998 Ferrari F1 (Schumacher's 2nd car - won Spa) is now owned by a friend, who mentioned that the idle is at 4,000 RPM. Raises this to 10,000 to get off the line.

Jim S.

 

Can they idle? Seems they are always poking the throttle to keep it going.

 

it might jstu sound like there poking at it the sme way it sounds like a old muscle car built for drag sounds like its poking at hte throttle its jsut about to die becuase its at such a low RPM and it dosnt wanna be there.

 

Yes they are able to idle and the will pull well from as little as 5000 rpm
what you have to think on is the stroke of the modern f1 engine is very short so to make it all happen,the camshafts have conical cam lobes and very hard to grind,there are no valve seats as such,no bucket type tappets,valve lift can anyone have a guess at that,
Dale.

 

lets look at an imaginary F! engine V10 104.4mm bore + 35 mm stroke

Displacement 2,997.55 cc

Intake valve size 40mm X 2
Exhaust Valve size 34.5mm X 2

Intake valve lift max 14mm
Exhaust Valve lift Max 12mm

needless to say with a short stroke and high max RPM valve float must be controlled very tightly to prevent any form of contact with the piston.

 

4,000-5,000 RPMs, just above the point where improper ignition timing may lead to detonation.

 

Uhm, all F1 cars have air actuated valves since about 1997 or so. No cams.

 

Sean;
The air or more correctly nitrogen is used as a replacement for the valve springs. there is still a cam controlling the valves. Experements have been done with electronic solinoids controlling the valves with out a cam the problem is weight placed up high on the motor.

 

Hi Beast 104mm bore is to big for f1 they would have to use twin plugs
and have problems with compression,try 97mm,
Sean f1 cars DO have cams-conical grind=less friction-hard to grind the shape,
ok i will tell you 17mm valve lift,
valve to piston clearance 0.2mm! time that up then,
last year toyota ran its cart engine to 17,000 rpm on wire springs,
come on there's someone out there who is going to post a picture of a 2004 f1 engine cam,somehow i think not
cheers
Dale.

 

Error---

All F1 cars since 1987 have used pneumatic valve springs, the cams are still there.

 

They don't idle on their own.. They either hit a button on the steering wheel which will put it into a certain mode to keep the idle (like when they pit) or they hold the accelerator manually.. If they lift off the accelerator the car will stall.

 

F1 cars do idle, it's just that they do so at high revs. I would suspect that some factors are:

1) With an insanely light flywheel (and other highly reduced rotational masses) there is a reduced inertia to keep the engine spinning through the next compression stroke.

2) Being an extremely oversquare motor (big bore/small stroke), it will naturally favor higher rev power production and barely run at low revs.

3) The cam duration (the degrees rotation where any valve, within a given cylinder, is open) and valve overlap (the degrees of rotation where the exhaust and intake valves, within a given cylinder, are open at the same time). Large degrees of duration and overlap extract the most power from an engine at higher revs (optimizing high rpm scavenging) but will not run efficiently at lower rpm ranges (low compression and burn efficiency) sometimes running some raw fuel from the intake right through to the exhaust pipes.

The poking at the throttle is to prevent loading/fouling of spark plugs with raw fuel and ensure that it stays running on all cylinders or even running at all.

Or...I could just be full of S**T.

Regards,
Bill

 

Dale;

Lets take a look at something here on the bore size.

At 104.4 mm Bore X 35 mm stroke the piston speed is 4363 feet per min.
This is not to bad for a race motor it allows less stress on the rotating masses of the motor.

A 97mm bore would have to have a 40.55 mm stroke to allow for a displacement close to the 3 litre maximum.

The piston Speed would be up to 5055 feet per min not unreasonable but a bit on the ragged edge.

All of this is using a 19,000 RPM figure.

As for the use of twin Spark plugs??? No it will not be neccesary since the proper design of a combustion chamber will allow for optimum flame probagation durring combustion. Plus on top of this the fuel air mixture is still burning by the time the Exhaust valve starts to open on the powerstroke.

Rob

 

On the Speed program where Montoya and Gordon switched cars, they pointed out that the Williams/BMW's idle speed was 10k rpm, and anything below 7500rpm would cause problems with the hydraulic pump not having enough output. The Nascar's redline was below the F1 cars idle speed!

 

A shorttrack (e.g. unrestricted) NASCAR engine will redline above 9,000 RPMs. All you have to do iw to watch the interial cameras durring a race and see the driver using the 7,500-9,000 power band as he exits one corner, zooms down the straight, and enters the next left-hander (why arn't there any right-handers?) I've seen as high as 9,400 RPMs on TV.

The hydraulic pump has nothing to do with the engine (other than being powered by it). The hydraulic pump runs the transmission. The pneumatic valves are run by a tank of compressed nitrogen (3000 PSI). At Indy (2002) The in-car camera of Rubens showed several parts of the infield being taken in the 11-13K RPM band, so there must be useful power down at least that low.