Interference/Noninterference Engines

[UncleBob]

Originally Posted by beef_bourito

actually you did say that interference motors have power and you were saying that a high horsepower engine MUST be interference and i was trying to say that it doesn't have to be. as curtis said, there's just no motivation to do it but it CAN be done.

you are correct, that first post I made, my tongue was thoroughly planted in my cheek. I shouldn't have expected anyone else to figure it out though. I know those things are very hard to translate over the net

But...."doesn't have to be" I definitely disagree with. There's a fine line between that, and NOT FEASIBLE. Which I've stated. Still waiting for someone to prove me wrong. No one has yet. I assume its because there's too many choices out there to chose from...? I'm patient. Take your time.

[TheSilentChamber]

Someone really smart once told me "if nobody else see's things your way... maby you should try seeing it theirs" Just some food for thought.

[UncleBob]

Originally Posted by TheSilentChamber

Someone really smart once told me "if nobody else see's things your way... maby you should try seeing it theirs" Just some food for thought.

Since you've yet to offer anything useful to this conversation other than biting comments, maybe you should consider your own advice?

I don't think anyone really disagree's with me, I'll be charitable and say that, most people don't consider my level of performance that I'm discussing worth discussion on stock engine applications.

But IMO, that would be true 10 years ago, but performance is always increasing, and motors are getting smaller due to fuel consumption and emissions concerns, so you can be sure that future cars will continue the same trend. And to go back to my point they will be intereference motors BECAUSE of that (higher performance). What is the exact, specific line in the sand that non-interefence motors isn't feasible anymore isn't really an issue, but my original point is still very valid: high performance (as I define it) requires reducing combustion chamber clearances, which makes non-interference motors pretty much impossible to achieve.

Do you have something to offer to dispute that?

My mommy once told me...junk food is bad for you

[TheSilentChamber]

I offered my part of the conversation on page 1. Retorical argueing is pointless, both motors can make power, but you see it more so in interfernce motors. End of story. There are alot of factors involved in designing a motor, some less obvious than others. End of story. Timing belts sometimes break for no apparent reason. End of story.

Your new here, and endless arguing and calling people out on stuff over and over even though both sides have allready been covered and there is no definative Yes or No answer to the question- is not a good way to start off.

[curtis73]

Originally Posted by UncleBob

I'm still looking for someone to tell me that I'm wrong. All I've gotten so far is "you're mostly right"

I'm sorry to say, but AF isn't a place where we dwell on right and wrong, black and white, or left and right. This is a discussion about benefits and drawbacks and there is no room for right and wrong. In case you didn't notice, my post (which was based in experience) was not biased toward any one person's opinion in this thread.

You need the valve lift to acheive good head flow

No, you need good head flow to achieve good head flow. If you're relying on valve lift to get head flow, then you've abandoned low-lift flow characteristics in favor of mass flow at peak VE. Great for a race engine, but terrible for the street.

Seems rather simple to me. Greater performance REQUIRES reduced combustion chamber tolerances.

Huh?? chamber tolerances? I'm not sure where you're going with this.

It doesn't have to be a difficult answer. Yes or no will work. The answer is rather obvious if you ask me, but it seems many here want to make it a difficult one.

Yes or no will NOT work. That's the whole point. Each one has trade-offs and benefits. If you entered this thread just to fluff your ego then you have joined the wrong forum. If everything in the automotive world were a yes or no answer, we'd all be driving the same car in the same color with the same options.

Its obvious that you are just here to press the benefits of multi-valve, small-displacement engines. In the Engineering/Technical forum (which, in case you have failed to realize... I am the moderator) we objectively discuss automotive engineering and technical things without prejudice, bias, or childish tantrums. There is no right or wrong when it comes to such a broad topic as how an engine designer configures an engine. Especially when YOU aren't the one designing them and singing the checks to put them in production.

This has just become argumentative..... Closed.