Huge Epiphany

[NOS2006]

At 1000 RPM, your engine is REVOLVING at 16.67 times per second.

At 3000 RPM, we're looking at three times that, or 50 times per second.

At 7000 RPM, we're speaking of 116.67 times per second.

And those high-revving 12,000 RPM engines hit a completely outrageous 200 revolutions per second!

Am I effing insane? Are these numbers completely off? I'm going crazy looking at these numbers. How the hell is that possible?!

If you take into account that these engines are four-stroke, does that mean they're actually doing four times more rotations than they are revolutions? Or less?

Edited March 23, 2007 by NOS2006

[Nick]

Some of those F1 engines rev in the 20,000 rpm range. It's pretty incredible to think about how fast those parts really are moving.

[Sixty8panther]

Yeah... the numbers are correct.

This is why rotary motors make so much sense.

Think about the fact that the piston has to go up

at those speeds, then stop and do a 180* and

it never stops until your key slips back out of

the ignition or something breaks.

A wankel does not have to stop and reverse

direction, it just keeps rotatinng in the same

direction. Radial motors are also stressed less

since they run in a 360* motion.

[quantum110]

At 1000 RPM, your engine is REVOLVING at 16.67 times per second.

Hehe...If your engine is revolving you have a problem.

[Z-06]

Yeah... the numbers are correct.

This is why rotary motors make so much sense.

Think about the fact that the piston has to go up

at those speeds, then stop and do a 180* and

it never stops until your key slips back out of

the ignition or something breaks.

A wankel does not have to stop and reverse

direction, it just keeps rotatinng in the same

direction. Radial motors are also stressed less

since they run in a 360* motion.

Mechanically rotating engines are good, stoichiometrically, they are difficult to control. That is why they have been not as advanced compared to the common piston types.

[76ChevyTrucker]

Y'all can call me crazy, but the moment I heard rotary engine, I immediately thought Pratt & Whitney Double Wasp, don't ask me why, but I did.

[Sixty8panther]

radial & rotary are two very different animals.

[Drew Dowdell]

If you take into account that these engines are four-stroke, does that mean they're actually doing four times more rotations than they are revolutions? Or less?

No.

Rotations = revolutions.

Typically, in 1 revolution of a 4 stroke engine, 1/2 of the total number of pistons fire. It takes two full revolutions of the crank for every cylinder to fire.

I'm sure this varies by crankshaft design... but it's fairly close.

[loki]

No.

Rotations = revolutions.

Typically, in 1 revolution of a 4 stroke engine, 1/2 of the total number of pistons fire. It takes two full revolutions of the crank for every cylinder to fire.

I'm sure this varies by crankshaft design... but it's fairly close.

wouldn't you mean 4 revolutions for every piston to fire?... take a 1 cylinder engine for example.

[Drew Dowdell]

wouldn't you mean 4 revolutions for every piston to fire?... take a 1 cylinder engine for example.

No... each stroke equals 180 turn of the crank. 1 Up stroke=Compression, 2 down stroke = ignition/expansion, 3 up stroke = exhaust, 4 down stroke = intake.

A 1 cylinder, 4 stroke engine fires once for every two rotations of the crank.

Edited March 29, 2007 by Oldsmoboi

[Sixty8panther]

Hmmm... I had my Datsun at 7200 rpm for a few sec. this AM.

[Chris_Doane]

Heh can I just ask if you really had this epiphany at 3:40 in the morning?

[Drew Dowdell]

and you people call yourself car fanatics..... don't even understand the basic process of a 4 stroke engine....*scoff*

I'm VERY disappointed in you....

Edited March 30, 2007 by Oldsmoboi

[loki]

dang, i miss interpreted what i looked at. lol

[FAPTurbo]

Jesus Christ that scared me...