Engine life

Shatto, why are you trying to introduce facts into this religous controversy???

OMG! Using sound logical reasoning is not allowed! Is it?

No Oldschool! No! Don’t do this! I beg of you!

(LOL)

Who said that high RPMs are good for an engine?
pleasedodgevan said so in the 5th post on here.

Of course turning more RPMs shortens the “time”, such as milliseconds, but not in degree of rotation of the crank. When you run you shorten the time between your feet hitting the ground compared to when you walk, but it has NOTHING to do with the arguement about 4s or 6s.

Well, to compare engines we would have to assume each engine would get the same tender care. Like keeping the RPMs dowm

How many 4s do you know od that are larger than 6s Most 6s have more didplacement and more power, Da!

Yep!!

It ain’t exactly the number of cylinders but amount of displacement and more power.

It’s big of you to finally admit that. Congratulations on you first step to true enlightenment.

Then I guess you are a “4 cylinder thinker” too since you wrote, “It ain’t exactly the number of cylinders but amount of displacement and more power.”

…unless it is designed to operate at high RPMs with longevity in mind.

I just checked, and I can’t find any place where pleasedodgevan said that.

Just like you did with Whitey, you have taken a statement out of context, added your own assumption about what he meant, and acted as though it means something other than what the author probably meant. The more you do this, the more I question your reading comprehension skills and your deductive reasoning skills.

Before you go around saying what pleasedodgevan meant by his statement that “higher engine speed helps a lot more than it hurts,” you should ASK HIM WHAT HE MEANT. ASK HIM WHICH ASPECT OF ENGINE PERFORMANCE IS “HELPED” BY “HIGHER ENGINE SPEED.”

If you keep going around taking peoples statements out of context and adding your own meanings, you will hamper your efforts to communicate clearly with others.

Saying something “helps” could mean so many different things, yet you claim to know what he meant by it. Chances are, you are dead wrong.

Going around spouting what you [i]think[/i] other people mean is both immature and ineffective. Perhaps if you don’t agree with someone, you should address that person.

Did you hear something? I thought I heard the sound of a gnat buzzing around my head, but I am not sure. Did you hear that? There it is again!

I hear it too!

This whole thread had degenerated into such an rankerous debate that I went back to and reread the OP’s original question.

In theory if all other factors are equal (engine design, build tolerances, maintenance, lubrication, etc., etc.) then the motor which turns lessor rpm’s over a given distance would last longer. In the real world all of the factors are in fact not equal. Therefore a well designed 4 might outlive a poorly designed V8. In fact my Honda 4 far outlasted my Cadillac HT4100 V8, but so did just about every other motor ever made.

If the debate must continue then carry on.

I have never meant that a well designed 4 cylinder could not last longer than a poorly designed 6 cylinder. I think we have to assume that Honda or Nisson, or Mazda designs their 6s with the same technology and expertice as they do their 4s. As you said above, the motor which turns lesser RPMs over a given distance would/should last longer. Let me add that that the one with the higher RPMs would have a lot more revolutions in a given time also. As the OP suggested.
Also, I know that all factors are not equal, but I don’t see why the factors should favor any particular engine.

jimhf, I believe your assumption is correct. I checked up on Mazda and Honda and their 4 cylinder engines in the Mazda 6 and Accord had slightly longer strokes than their 6 cylinder engines (no much) which should add to the wear.
The Mazda 4 produces 168 HP @ 6000 The 6 produces 272 @ 6250.
The Accord 190 HP @ 7000 271 @ 6200 I know, this is irrelevant, but just threw it in.

Maybe if you ignore EllyEllis he will stop repeating himself.

It is impossible to shorten the duration of the sparks and irrelevant means “does not apply to the situation”. That makes it IRRELEVANT.

To delve further on 6-cyls that rev higher than 4s, consider:

Typically in automotive applications, more cylinders are used because more displacement is desired, and simply “scaling up” a 4, for example, produces undesirable results. Thus, displacement/cylinder stays staedy or goes up. Such a scenario favors decreasing RPM with cyl. #.

But it needen’t be that way. If cylinder # is increased, while holding displacement constant, you 1. reduce peak piston speed @ RPM due to a shorter stroke, 2. by decreasing cyl. volume, you increase surface area to volume, allowing the cylinder to “breathe better.” Both of these trends tend to increase, not decrease, RPM.

This is a quite common phenomenon in motorcycles. A 4-cyl, 1L engine will rev much higher than a 1L twin.

Actually, I’ve always thought a 2.5L or so V8 would be a fun (albeit expensive) little engine for a compact sports car…