56mph

Although that seems very slow it is correct for an average speed but that includes 2 stops with acceleration and deceleration for each. FYI, The maximum velocity of the piston is approximatley 88.625 mph.

 

[QUOTE=SheDrivesIt,Dec 13 2005, 04:02 PM]

 

^^Oops it looks like there were about 10 posts between loading the page and actually posting. If you want to calculate the max speed of the piston you need to calculate the distance of the crankshafts travel aka circumference (stroke X pi) and then plug in the revolutions per second (150) and divide by 12 to get feet per second. Then you can convert into mph.

 

It will take a lot of reading to come over more crap than what was posted on this page alone -)))))) Good job guys, at least we are all s2k fans and wont tell anyone out there.

To explain it a little bit easier to the original poster.

Take 2 persons and tell them to run a different distance there and back (around 2 cones let me say) 10 times. If person A has to run a longer distance than person B, but finish in the same amount of time, he will need to run faster, right?
Similar to a needle on a vynil record. At the beginning of the record, the needle "runs" faster, even tho the revolutions remain the same all the time.The F20C is a big vynil a F1 is a rather smaller one.

 

ooooooooooooh....this sounds berry interesting.




wish I understand some of it............sighing.

 

In an article on the forthcoming RS-4 on Audiworld, there's a comment about this whole piston-speed thing.

They talk in terms of mean speed (which is the central calculation made here) and state that the V8 in the RS-4 has speeds (at 8250rpm) that equal those of the 19000rpm Renault -- 25.7m/s = ~57.8mph. Thus, the 56mph noted here is in the right ballpark and, all things considered, pretty fast.

That RS-4, by the way, sounds like a hell of a little sedan. HPH

 

Very neat website. I just wish he had an option of metric, and could display accerlation in terms of g's, rather than miles per hour per hour.

Anyway, your numbers are a tad off. The website uses the crank radius in the calculations, which is 1/2 the stroke. Putting in the F20C1 numbers (1.65in radius, 6.02in rod and 9000rpm) yields a max instantaneous speed of 91.839 mph. Doing the same for the F22C yields 91.051 mph at 8200rpm.

 

Oh, and the pistons of the F22C see 4443 g's of accerlation down when it's near the top of its stroke.

 

If you don't understand what is being discussed, check out http://auto.howstuffworks.com/engine.htm. Helped me years ago when I was first getting into cars.
Here's a great site about Formula 1 engines. http://www.pureluckdesign.com/ferrar...lumn/index.htm. It explains the short stroke compared to bore, as well as other interesting aspects (such as air-pistons instead of valve springs).

 

Oops, good catch. I thought it was crank diameter. That makes a lot more sense now actually