i agree what your saying about detuned engines, thats the way the 2jz-gte (supra TT engine) and the rb26dett(skyline gtr engine) come. they lower boost and restrict airfow alot to lower insurance and to keep japans gentalmans agreement of 280ps.

Sorry to join thread late... however...

I have to agree with 2ndGenTeg and spoogenet, there is no ignoring the hp/L number when arguing over displacement as king. All internal combustion engines are fancified AIR PUMPS, and the more taken in the front and pumped out the back, the more torque/hp any given displacement will make. The practical limit for this is whenever you cram so much air and fuel into a motor that the mixture attains enough heat to pre-ignite(detonation). There are a lot of things that affect the ability of an engine to inhibit detonation, but the foremost contributor is the compression ratio(CR)!

Upping the CR increases power... to a point, that being when the motor experiences detonation. A primary inhibitor of detonation is... swirl! Swirl is the relative turbulence of the intake charge(when the piston is approaching TDC during compression, especially) and there are many factors that contribute to swirl, among them:
piston/head design
valves per cylinder(more increases swirl)

The piston and head design is doubly important because it not only can increase swirl, but also control detonation through even distribution of heat in the combustion chamber. Spark plug location within the head determines the rate and pattern of flame propagation during the power stroke(this has the potential to make or break an engine: think of the hemi; it is successful due to a combination of these principals.) More than two valves per cylinder(think DOHC) leads to better intake and exhaust flow: the smaller passages create air that moves more quickly and with more turbulence, both adding power.

Ahh... whoops, I kinda went off there... but I think the most important thing to note about FI vs. NA is that if you're adding forced induction, you're essentially increasing displacement by cramming more air into the same space, whereas a larger motor will intake a similarly larger amount of air without the coersion of a super/turbo - charger... and you'll hit a ceiling of performance. Then what happens when your buddy/opponent slaps a 'charger on his larger motor of equal specific output? You're toast...

Happy trails...

BTW this Enzo engine is a large ci motor about the size of mine.. so I guess that's FOR no replacement for displacement? Why didn't ferarri use a turbo or twin turboed 1.8 or 2.0?

Bro, your missing the point here. I'm stating that if the saying was true and you have a V8 with that much cu in, and a V12 has the same.....the statement can't be true. 4 more cyclinders and the same cu in.


I'm starting to think here that your missing the point so bad that if you jumped ship in the middle of the Atlantic you wouldn't find water.

oh my.. do you know anything about motors?? If you say that the difference is the xtra 4 cyl is what makes that power, then you don't. Also, the 572ci motor is an 8 cyl and makes more power than the enzo motor... why is that? The enzo has 4 more cyls... so it should be more powerful? What you are saying is that the enzo motor's "replacement for displacement" is the xtra 4 cyls... well apparently not since the 572ci mountain motor owns the enzo motor.

And I'm going to use the all time famous V8 response to this one......."Do the same to the Ferrari"

ram air really does nothing for your car untill high speeds, like over 60mph then it pulls harder yes, its only because at that speed theres enough force to "ram the air" into the intake which is directly connected to the throttle body, instead of going thru tubes and bends and shit like that! most intakes are about like what....a foot long? ram air all it is, its a box, MAF, throttle body!....well you guyys can talk all you want about hp/L i really don't give to shits!

and 572ci motor = 720hp... again no replacement...this will be my final point because this proves it without a doubt.

BAHAHAHAHA, no this doesn't prove it.


The statement "There is no replacement for displacement" states no matter the displacement, as long as it's larger, it ALWAYS, cause remember there is no replacement for it, has more hp. And it's not true!!!

Look at the Viper vs Enzo.


Thank you drive through!!!!!


And the best part is, you have to mod the car in order to have "your" agruement. I haven't modded ANY car in "my" arguement, atleast I don't remember doing so.

And...


I didn't want to do it but I'm going to anyway

Chevrolet Callaway Sledgehammer Corvette
5733 cc / 349.8 cu in
880.0 bhp @ 6250 rpm

Mercedes-Benz W125
5577 cc / 340.3 cu in
736 bhp @ 5800 rpm

So you can now take that saying and throw it out the door. And that Mercedes-Benz is a V12 also.

So put that in your cab and drive around with it.

The Callaway is a modded car... and the 572 is not.. right from GM out 'O their catalog. So now YOU are talking modded cars. And the enzo is a large displacement motor.. like I said, no replacement.. btw you didn't answer my question... why didn't ferarri use a 1.8L or a 2.0L and twin turbo those or something along those lines? Why would they use a LARGER DISPLACEMENT engine? Interesting....

OH I've got to see this. PLEASE show me where a 572 from chevy is FACTORY!

And either way, if it's factory or if it's modded....your statement still isn't true then and you prove my own point. "LARGER DISPLACEMENT" would still be king, and it isn't. See my final post.


Chevrolet Callaway Sledgehammer Corvette
5733 cc / 349.8 cu in
880.0 bhp @ 6250 rpm


If your statement was true, your 572 would make more HP cause it has more displacement. either way you look at it, you got owned.

I posted the link earlier.. please pay attention.

First you complain aboutme using modded engines... so I show ya one from GM.. the 572.. then you compare it to your modded vette... please.. you are getting yourself confues.. pulling stuff out of your ass.. again I ask and you don't answer... why doesn't ferrari use a 1.8 or 2.0L engine?

3586 cc / 218.8 cu in, that's the Modena engine. 3496 cc / 213.3 cu in is a F355 engine. 2936 cc / 179.2 cu in and 478 bhp @ 7000 rpm is a F40 motor. How's that for small liters!!!! 478 hp out of a 2.9ltr. Small enough for ya.

And if that isn't enough, 2997 cc / 182.9 cu in that produces an even 770hp is also made by Ferrari. It's an Indy car, LOL, but reguardless, still proves the point. Technology is the replacement for displacement! 3.0ltrs with 770hp.....OWNED!

And you still won't explain to me how this works if your statement is true....

5733 cc / 349.8 cu in
880.0 bhp @ 6250 rpm

HOW CAN THIS BE TRUE IF YOUR STATEMENT STATES THERE IS NO REPLACEMENT FOR DISPLACEMENT!!!



I just think that someone can't admit when they are wrong. Typical guy, I won't admit when I'm wrong either, but I can admit it to myself. Wonder if you can.

dont know who did, but the lingenfilter(sp?) vette is also a modded car, as is the saleen mustang. independently tuned by a different manufacuter then sold to a dealership

Modded vs. Stock- Why does it matter? Wouldn't those mods be replacement for displacement? Wouldn't ANYTHING that increases output other than displacement be a replacement? And if the Enzo motor is the same size as yours, does that mean yours is just as fast? By the no replacement for displacement theory, the two motors should perform IDENTICALLY because they are the same size.

By no replacement for displacement, every 1.8L motor would have the same output, PERIOD. Every 400ci motor would have the same output, PERIOD. Every motor would have the same specific output, PERIOD. All three of these are false.

There seems to be some confusion about ram air. Ram air is creating boost by traveling at speeds such that there is a compression effect in the charge air. Ram air does not START until speeds of about Mach .5 (half the speed of sound!) are reached. And if you're reaching half the speed of sound in the 1320, I don't think you really need boost.

True. but I doubt he meant more than what the sticker on the side of his car says. Guess Pontiac thought "Ram-Air" sounded good. Better than "Lotta-Air" I guess.

i know that to create ram air but forcing air, you must be travling that fast, but what about the ram air things(lack of better name) KART cars used a few years back before they were determined unfair? those produced a ram air affect above 150mph or so didnt they? they had a vaccum design though, not jsut ponding air at the air filter

I didn't think Ram Air truly worked at such low speeds, thanks for adding that bit Teg.

00 Si....aka Mr. :banana:.....

WHAT IS YOUR POINT? I ask it in as nice a way as possible while still yelling in all caps. Are you trying to say that higher displacement always has higher power? If so, then you truly don't understand anything about engine design. Let's take an extreme approach.....two engines, each have the same block and displacement, same pistons, rods, cams, valves, valve springs, throttle bodies, heads, plugs. Which one makes more power than the other? It's undeterminable until considering the intake and exhaust manifolds, timing, A/F ratio, and a few other things. That is kinda where the technology changes the power of any given engine. Of course by changing pistons, cams, heads, and other things then the engines are capable of even more or less power than they come with stock even while maintaining the exact same displacement.

Oh, and you can't fairly compare F1 cars to normal cars....they don't run on gasoline like you and me can buy at the local Chevron or something. If you really want to open the door, I'll argue that my daddy's F15 produces more thrust than your daddy's Civic Si. W00t!!!!!

Assumption: All blocks are capable of handling extraordinary amounts of power.

That assumed, one can conclude that the theoretical maximum power output of an engine is proportional to its displacement, thus higher displacement engines are always capable of more power than smaller displacement engines. This does not mean that the actual power output will be proportional to displacement. Actual vs. theoretical is a very different ballgame.

I will give this one its own line:

Theoretical maximum power is determined and limited by physics and mechanics whereas actual power is determined and limited by engineering and manufacturing.

b

Another problem with the Ram Air designs of many cars is that the faster you go the less airflow exists over the hood. The bow wave of the car causes a low pressure area above the hood, hence the simple principle of how a car acts like a wing. Downforce becomes necessary.

Anyhow, that's why you notice that in drag cars the intakes are always mounted high up, more like a snorkel. This is such that as they get going fast enough the snorkel is still in the higher pressure region rather than trapped in the low pressure region.

My guess is that the ram air designs are purely marketing tools, but I don't know. They certainly don't look like they're very functional, but I couldn't say. Best bet would be to take the same engine in the same car, and give one a non "ram air" intake system while leaving the other stock, and race the two. Accounting for any difference in pressure drop through an intake tube could be done carefully on a dyno to ensure an even fairer test. I wouldn't be surprised if the two come out equal, or even if the non ram air one wins.

b

he sumed it up here, 9:1 compression(just a number) will produce x amount of torque(read: real power) in a 4000cc engine(again, just a number) if you increase compression(via pistons or forced induction) you are increasing the engines power output. that is a fact of physics, the replacment for adding displacment is increasing the amount of air going into the combustion chamber then compressed, increasing the oxygen levels(n2o) or increasing the piston compression, or changing cam profiles are ways to increase the engines total output without changing the size of the engine.you can increase displacment to an extent on any block, and keep all other factors the same, and increase tq. you may not gain more hp, but more air will 99% of the time = more power considering you are not delivering increadably hot air(via poor turbo set up etc) to the engine. this theory applys to all engines i can think of. if there is one i forgot, dont ream me, state my error in a constructive matter. i know the engine layouts (v6 v8v10v12 or the VW W engines, opposing V engines, inline and boxer engines) also comes into play, but for the sake of this conversation, i dont think we need people with engeneering degrees explaning this to us, same thing with pushrod vs OHC setups. they are WAY beyond the technical competance of what this argument is.

ferrari increased power by having high compression pistons
porsche uses a turbo on a smaller engine
honda uses a variable valve lift on some engines
nissan and toyota use turbos sometimes
we will say for the sake of a benchmark that the standard american domestic engine is the origional engine because it was, these different companys have taken the design and built off it, improved in some eyes, changed for the worse in others.

rotory engines are not vaild, i know i brought them up, but thats a different technology than a crank and rod engine all together. 0.65Lx2(2 rotor engine, each one with .65L of displacment) yeilding 280hp STOCK is just crazy

Nothing against your banana....I like bananas too.

Toyota also uses VVTi, though. They change valve timing and fuel mapping, similar to VTEC, but it also maps out how you drive and adjusts the A/F for power or efficiency depending on what it thinks you want. :) I'm not sure how much of an effect it really has on power, but then again I don't know how much VTEC influences power either. Well, ok, I know that Toyota's VVTi can actually give you less power than your car is capable of if it thinks you want efficiency.......hmmm, I don't like that system.

b

i think enough points have got proven...im getting a headache from reading...im not a real engine/displacement kinda guy...:no: :crazy: :eek: :pukey

its not over until i make my point. the term can be looked at in more than one way. it seems the displacement guys look at it in one way (when all else is even) and the small displacement guys look at it in another (i can make my 2.0 as fast as your 5.0) and to argue in this fashion gets nowhere. its a moot point. moot! moot i tell you!
:|

now its over....unless someone wants to compliment me on my genius.
:|

he's right.. you would have to specifically define the saying "no replacement for displacement"... too many variables...

I'm not saying I look at it from my 2.0 can be faster than your 5.0. I look at it from the stand point.....

"There is no replacement for displacement" meaning to me that if there is a motor with more displacement, it should always win because there is no replacement for it. And everyone knows that isn't true. Hence the Sledgehammer Vette. All that power out of a 349.


Now am I correct? Who knows, who cares. I just enjoyed the debate about it.


:bandit:

Is that what this thread was?:D

I'm not saying I look at it from my 2.0 can be faster than your 5.0. I look at it from the stand point.....

"There is no replacement for displacement" meaning to me that if there is a motor with more displacement, it should always win because there is no replacement for it. And everyone knows that isn't true. Hence the Sledgehammer Vette. All that power out of a 349.

so basically, even though you denied it, you are looking at it from the "my 2.0 can beat your 5.0" standpoint. you are saying that the phrase means: a motor with more displacement should always be faster. but you disagree with this statement...you said it's a 'crock' remember? therefore you think that small displacement engines can be as fast as large displacement...ie a 2.0ltr can beat a 5.0ltr
and by the way, im not arguing the validity of any of these statements im trying to point out the form of the argument itself. itself. (im a in a philosophy class so this is good practice for me:yes: )
:|

i guess i didn't do that quoting thing right, eh?
:|

LOL

And I'm not saying I look at it in ltrs. I'm looking at it from a cu in standpoint. Just due to more cu in doesn't make it faster or more powerful. So there would be a replacement for it.