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CYA
December 18th, 2001, 11:57 AM
so lately i've been thinking about that whole thing about how the old folks came up with that no replacement for displacement saying. i myself have never really believed in it. sure larger displacement is easier to make hp but is it as simple as that??

people always say whoa... if honda made a 5.0L displacement motor this would kill the 5.0L ford. but if you take both and put a 92 pump gas restriction on each i think the results wouldn't be as most would think? the thing i'm thinking about is that it's not so much displacement but number of cylinders. the ford 5.0L being an 8 cylinder engine should be able to make the same HP at a MUCH lower compression than the 4 cylinder 5.0L honda.

i dunno... just random thoughts in the rough stages. never really put a lot of thought into it. just thought i'd see if anyone else has ever thought about it?

CYA

TALONV8KILLER
December 18th, 2001, 12:30 PM
Maybe , but the 3.0 NSX on 92 oct makes 320 hp versus the 5.0 on 92 oct making http://www.asianet.ca/images/iB_html/non-cgi/emoticons/confused.gif?
I didn't even have to look it up , it will of course be less.

WITH OUT PREDJUDICE

CYA
December 18th, 2001, 12:35 PM
yes but... my 5.8 makes over 600hp on 92 octane gas. *wayne's 5.0 runs 124mph on 92 octane gas. *http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif *how much power can the 6 cylinder nsx make on 92 octane? *that's the stuff i'm thinking about.

oh yeah... and that's non-intercooled... intercool it and do whatever to each motor... and i still think the other motor would be limited to number of cylinders and the resultant compression.

(Edited by CYA at 10:38 am on Dec. 18, 2001)

TALONV8KILLER
December 18th, 2001, 04:24 PM
We must be talking about different things here.
The NSX isn't force fed , its a N.A. 3.0L @ 320 hp.
You say your after market super charged 5.8L
engines have 600+ hp.
So say you put a extra atmosphere through a 3.0L NSX
what will happen?
I'll try to find out what if any 5.0L Honda engines out there made for HP and let you know.
Should I compare a NA against NA or NA against after market blower?

CYA
December 18th, 2001, 04:43 PM
no we're talking about the same thing... you're just not seeing the key part of my thoughts. 92 octane restriction.

if you add the boost to the nsx motor... what will happen? well... if you put that much into it who knows... but it won't like to run on 92 octane gas.

like i said... do whatever you want to each motor and it will still be limited to the number of cylinders and resultant compression. i.e. put however much boost you want into that nsx motor... but... run it on that 92 octane gas.

compression is compression... doesn't matter how you get it... be it through domed pistons, smaller combustion chambers, turbo, supercharger, whatever... those 6 cylinders are where the hp is made. when you add in another 2 cylinders the 8 cylinder engine can now spread the hp output between 8 combustion chambers instead of 6.

Cyanide Ride
December 18th, 2001, 05:18 PM
Doesn't Comptech have a streetable bolt-on supercharger for the NSX that makes 420hp on 92oct?.

CYA
December 18th, 2001, 05:39 PM
ok let's say they do... that's 420hp... we're well into ther 5's on 92. and we're just edmonton examples... if we go down south of the border there are even higher powered 8 cylinder cars on 92 octane.

never said that decent hp can't be made if you don't have 8+ cylinders... i'm just saying that it becomes a restriction since you are going to run higher compression to get that power.

TALONV8KILLER
December 18th, 2001, 06:20 PM
Compression is not just compression and It does matter how you get it.
If you run a 5.0 NA at maximum capable tuninig the best you will do is around 4.7L of intaked air/ fuel mixture per 8 intake strokes.
I don't care if you have 15:1 comp or 7:1 comp you will only get so much power per volume of air/ fuel mixture.
The higher compression will yield more power to a point but the end result is you can only burn the air/ fuel you have.
Now if you pump 4L of air/fuel into a 2L engine you will have more to burn hense more btu's hense more power on tap.
So it does matter how you get the compression.
Compression through cramming air and fuel into a cylinder will make more power than a 12:1 compression NA engine of the same size.
Its best to run 8.5:1 with 20psi boost than 12:1 with no boost.
Both of those will run on 92 oct.
There are Talons with 8.5:1 and 21 psi on 92 oct running over 500 hp with 2.0L for example and then turning the boost to 30 on C-16 and getting 750hp.

Anyways lets get back on track.

The reason the smaller engines make more HP / CI is they run higher rev's and use things like VTEC and modern engine designs not like the tech the detroit boys are brain washed with.
The fact is Honda could build a 5.0L 600hp NA that runs on 92 oct if they wanted to.
They have a 1.4 NA with 1500HP now so I think they could if they wanted to.
I will check the net maybe they have done it already!

WITHOUT PREDJUDICE

Loose
December 18th, 2001, 07:21 PM
Here’s my take on it. I hope I’m not being redundant with comments that you two have already made.

The power of an engine is defined mostly by 4 parameters:
1. displacement
2. volumetric efficiency
3. engine speed
4. thermodynamic efficiency

Multiply 1, 2, and 3 and you get the air-flow into the engine (in a sort of arbitrary mass flow dimension). This air receives a certain amount fuel, and #4 defines how efficiently it is burned.

Now things get more complicated…

#2 is a function of the intake, exhaust, heads, etc. and the number of cylinders. I will elaborate on how the number of cylinders affects the volumetric efficiency. If you have to breath through a straw, air only flows up the straw when you inhale. Just like an engine on it’s intake stroke. So for you to breath, half of the time you are not pulling in air. An engine works like this because each cylinder only pulls in air on ~1/4 of it’s motion. The more cylinders you have, the more continuous the air-flow is. To achieve the highest volumetric efficiency, continuous flow is what you want. Not pulsating flow. So considering this, theoretically the ideal number of cylinders is infinite. Of course you start to get to a “good enough” level well before you get up to 20 cylinders for example.

However, the more cylinders you have, the more losses there are from friction. 12 small cylinders has more friction than 1 big one, right? I’m guessing the ideal number of cylinders, considering many other factors, is probably around 10. Why? F1 uses 10 cylinders, need I say more?

4 is dependent on compression ratio of course, and limited by octane along with combustion chamber shape, etc.

About the Honda with a 5.0L motor vs a Ford 5.0 motor, lets imagine “Honda technology” with that much displacement. The closest I think you’ll find is a Ferrari F50 with 4.7L and 520hp (pump gas). That is an example of what great volumetric efficiency and high RPM can do together.

Anyway, I’m out, hope that clarifies something to someone.

Loose
December 18th, 2001, 07:23 PM
Please tell me more about this motor.

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
They have a 1.4 NA with 1500HP now so I think they could if they wanted to.
I will check the net maybe they have done it already!

WITHOUT PREDJUDICE

[/b][/quote]

CYA
December 18th, 2001, 11:15 PM
(Edited by CYA at 9:27 pm on Dec. 18, 2001)

CYA
December 18th, 2001, 11:27 PM
Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
If you run a 5.0 NA at maximum capable tuninig the best you will do is around 4.7L of intaked air/ fuel mixture per 8 intake strokes.


given a fixed efficiency range then yes... but in the real world efficiency is dictacted by the combination so you cannot simply state all it will do is 4.7L


Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
I don't care if you have 15:1 comp or 7:1 comp you will only get so much power per volume of air/ fuel mixture.
The higher compression will yield more power to a point but the end result is you can only burn the air/ fuel you have.

of course you can only burn the air/fuel charge that you have... when did i say you could ignite something else? what was the point in this? and yes... higher compression only gives more power to a point... when did i say there is no limit to power from higher compression?

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
Now if you pump 4L of air/fuel into a 2L engine you will have more to burn hense more btu's hense more power on tap.

more power than what? what is your comparison? forcing 10L into a 5L will make even more power... but what is the point in your statement? how does it relate to the topic?

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
So it does matter how you get the compression. Compression through cramming air and fuel into a cylinder will make more power than a 12:1 compression NA engine of the same size.

based on what can you make this claim? which variables do you keep constant and which variables do you change when determining if this is true?

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
Its best to run 8.5:1 with 20psi boost than 12:1 with no boost.

8.5:1 with 20psi of boost would be a higher dynamic compression than 12:1? i'll have to dig up the formula which gives a ball park ratio to be sure. but again... what's the point? these are all just numbers being tossed around... my original thought was about cylinder restrictions and how giving a fixed variable like 92 octane gas would affect power production.

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
There are Talons with 8.5:1 and 21 psi on 92 oct running over 500 hp with 2.0L for example and then turning the boost to 30 on C-16 and getting 750hp.

and how common are these? think any joe blow can put one together? no... these have to be tuned by someone who knows what they're doing. i'm sure with a t-trim supercharger and an intercooler i could come close to the 750hp output of that talon (when it's running the c16) and i'm on pump gas. of course i'd need some tuning other than a bit of timing taken out on the higher rpms like what i have now. and again... i'm just an average joe who slapped some parts on my car... that talon on the other hand, is a sponsored race car. that's two ends on the scale. i'm still thinking number of cylinders being a restriction.

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
The reason the smaller engines make more HP / CI is they run higher rev's and use things like VTEC and modern engine designs

yes... honda has excellent hp/ci but again... this is not a debtate about volumetric efficiency... it is about the limits of a 4/6/8/10/12/16 etc cylinder engine when given 92 octane gas to work with.

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
The fact is Honda could build a 5.0L 600hp NA that runs on 92 oct if they wanted to.

i never said honda couldn't... heck even kia could. but the real fact is honda would have to use higher compression than typical 10.5:1 (if they stuck with a 4 cylinder) that they tend to run now. and that is why they do not offer such a beast... nevermind warranty on it.

Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
They have a 1.4 NA with 1500HP now so I think they could if they wanted to.


again... the debate isn't about volumetric efficiency... it's about the 92 pump gas restriction and 4/5/6/8/10/12/16/ cylinders and high output.

(Edited by CYA at 11http://www.asianet.ca/images/iB_html/non-cgi/emoticons/wow.gif0 pm on Dec. 18, 2001)

CYA
December 18th, 2001, 11:29 PM
lol... ok i give up on trying to edit my post... mark... your board is messed. i really don't see where i have messed up on my quote tags. lol.

KillerRabbit
December 18th, 2001, 11:47 PM
Cya:
You in the market for a good t-rex pump http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif

CYA
December 18th, 2001, 11:56 PM
killerrabbit - lol... very tempting... guess it depends on the price. http://www.asianet.ca/images/iB_html/non-cgi/emoticons/wink.gif cause i was actually banking on the dual intank pumps but if it's a good deal... well... how can i pass that up? of course i'd think you'll get more money somewhere else though. just to forewarn ya. lol.

i'm assuming the t-rex we're talking about is just doing a full circle? i.e. coming back to the original owner? or is this another unit altogether?

mitsuman
December 19th, 2001, 12:09 AM
This is the way I see it...We have two motors, engineered by MB motors....bla bla bla.... * http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif

First motor is a 2.5 liter 4 cylinder, turboed at 7 psi, lets say 9:1 compresion. *The second motor two of the above except mated into a V8 (5L)configuration now having two intakes (same as the 4 cylinder). *The only difference is the V8 is a twin turbo at 7 psi (1 turbo per bank), same turbos as on the first 4 cyl motor. *Now lets say that at 92 Oct, the detonation threshold is just over 7 psi. *Both of these motors are tuned to the max!

So.....Its easy to say which will have more power. * In a case like this.. I hate to say it, but there is no replacement for displacement!

These just my thoughts with out diverting of the "question" path....

M

(Edited by mitsuman at 10:11 pm on Dec. 18, 2001)

TALONV8KILLER
December 19th, 2001, 10:47 AM
It's 8:30 in the morning and I'm at work.
There is no way I can reply to this totally out of hand forum.LOLOLOL
My boss will catch me for sure , so it will have to wait until I finish my shopping tonight.

All I can say is we both are screwed up and missing each others points. That includes you Marcin(read all the posts then edit your post bud)

Talk to you tonight.

One last thing- I'm just a every day Joe and I'll show you 500 HP @ the crank next summer on a 2.0L engine on 92 oct.

Talk to you tonight guys.

Cyanide Ride
December 19th, 2001, 11:02 AM
Gee, I remember starting out a similar thread with Cya on Edmonton online regarding displacement, volumetric efficiency, engine speed, and thermodynamic efficiency.

I remember saying something like You take the same supercharger and apply it on two different motors and tune them to peak efficiency, you're going to end up with more power on the V8...

Sam?, h*llo, Sam!? http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif

CYA
December 19th, 2001, 11:27 AM
lol... so maybe i didn't read it? http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif or maybe i'm losing my mind? haha. oh well... it was just a thought that i had since i'm so bored ripping around in the neon. lol. had a chance to fire up the mustang last night though. d*amn that's fun! http://www.asianet.ca/images/iB_html/non-cgi/emoticons/smile.gif

Talonts96
December 19th, 2001, 11:30 AM
Ok! I'm still not sure what this discussion is REALLY about? CYA is it the number of cylinders that youre talkinga bout or bigger displaceent. I dont really think the higher number of cylinders is really the big gain here. I dont think you could get more power or overall compression from a 4.0L V8 vs a 4.0L inline 4. The reason is youre pumping the same amount of air and fuel into both systems. The compression limitations should be the same for both. lets say 10:1. On the V8 combustion chamber (cyliner) would be 0.5 L in volume and your limitation on pump gas would be whatever it may be lets say 10:1 for the arguments sake. On the 4 cylinder engine each combustion chamber (cylinder would be) 1L and the compression limitation should still be the same on pump gas. Of course since the cylinders would be half the size on the V8 you would probably be able to rev it higher safely. All in all it should be close the way I see it cause youre burning the same amount of air and the same amount of fuel in both cases.

However if were comparing a V8 with twice the displacement lets say a 4.0L v8 to a 2.0L inline four. I agree with CYA and Mitsuman on pump gas all being equal (n/a...or blown) the V8 Should produce a lot more power.

TALONV8KILLER
December 19th, 2001, 03:46 PM
I'LL SLIP THIS IN QUICK.
Geez Paul your funny of course it will you turd.
The origional question was is their replacement for displacement?
Yes there is even at 92 oct.
Oh before anyone asks you will not get double the power out of a engine just by doubling its size.
EX:2L 4 cyl made into a 4L 8 cyl out of the exact same parts.
Who agree's and who dosn't.
I'll address the rest later.

Loose
December 19th, 2001, 04:03 PM
I disagree, explain your theory.

CYA
December 19th, 2001, 04:29 PM
talonts96 - yes we're talking number of cylinders. your example works if you ignore the physics behind an actual engine but the thing is with that 4.0L 4cyl the stroke would be enormous. lol. and because the stroke has changed to get that same 4.0L of displacement in the 4cyl compression will be different as well. all the other physics behind it will differ making power output change as well. the comparison can't be broken down to such a simple level.

talonv8killer - of course doubling displacement will not double power output. but once again... the debate isn't about "replacement for displacement". but since you mentioned it... doubling the displacement (using your example) will generally net increased power output capability.

TALONV8KILLER
December 19th, 2001, 04:42 PM
CYA - I cya point.
Loose - I'll give your engineering brain one phrase and see if you can answer it your self.
Does a piston and rod from a 8CYL 2.0L wieght 1/2 of a piston and rod from a 8CYL 4.0L?

Is there exactly 1/2 of internal friction?

Is there?

Is there?

Loose
December 19th, 2001, 05:19 PM
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from TALONV8KILLER on 2:42 pm on Dec. 19, 2001

Does a piston and rod from a 8CYL 2.0L wieght 1/2 of a piston and rod from a 8CYL 4.0L?

Is there exactly 1/2 of internal friction?

Is there?

Is there?
[/b][/quote]

Sigh,
The piston and rods DO weigh exactly the same and have the same friction. *You stipulated that the engines be made of *exactly* the same parts, so I don't see how things could be any other way.

..more about the friction issue, friction on the all parts will be exactly the same. *The only thing is that on the crank... a 4 cylinder and 8 cylinder engine have the same number of main bearings, so it is probable that the V8 might make even more than double the power of a similar 4 cylinder.

It's a moot point however, since these differences in friction level are insignificant relative to the gross power of an engine.

Any other questions?


(Edited by Loose at 3:50 pm on Dec. 19, 2001)

Loose
December 19th, 2001, 05:22 PM
and now your saying 8cyl 2L vs an 8cyl 4L?

Before the conditions were a 4cyl 2L vs an 8cyl 4L

TALONV8KILLER
December 19th, 2001, 06:42 PM
My post said 8cyl 2.0 vs 8cyl 4.0
My question is would the parts be half the wieght you st?http://www.asianet.ca/images/iB_html/non-cgi/emoticons/confused.gif Li?http://www.asianet.ca/images/iB_html/non-cgi/emoticons/confused.gif S??? (LOLOLOL)
WELL?
Also your bore would not be double so your valve area would be disperportionate to the sum of the valve area in the 2.0.
Meaning less intake possiblities to flow the 4.0 in relation to the 2.0.
-Less flow vs displacment
-more wieght internally vs displacment
-physics of engine working against you

Do you agree now that a identical engine doubled in displacment won't make double the power?

Does anybody agree or should I take it that you all disagree.

Loose
December 19th, 2001, 07:13 PM
Roger resorts to name calling again since he know's he's in an uphill battle. Big surprise. Big maturity from someone old enough to be my dad.


Anyway.....down to buisness.

This is what I'm talking about:

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Oh before anyone asks you will not get double the power out of a engine just by doubling its size.
EX:2L 4 cyl made into a 4L 8 cyl out of the exact same parts.
Who agree's and who dosn't.
I'll address the rest later.


[/b][/quote]

Quit trying to change the subject. Tell me why 4L V8 will not make double the power of a 2L inline 4.

TALONV8KILLER
December 20th, 2001, 10:07 AM
Well loose sense you love to selectivly read , selectivly read this : A 4.0L 8CYL WILL NOT MAKE DOUBLE THE POWER OF 2.0L 8CYL OF THE SAME DESIGN.

LOOSE(CHRIS) YOU ARE THE BIGGEST CRITIC OF THE PEOPLE WHO HAVE PRODUCED IN IMPORT RACING FOR SOMEONE WHO NEVER HAS , YOU LOOSER.

EVEN YOUR USER NAME IS ONLY MISSING THE R TO FINISH WHAT YOU REALLY ARE!

Well bud lets talk about maturity.
446-1553
be a man if you can!

Loose
December 20th, 2001, 11:49 AM
1. No I'm not going to call you, if you have something to say in between the two of us, use the private messaging on the forum.

2. Just because you own a fast car or have won a couple Battles does not mean you automatically "win" at any sort of technical debate.

3. You chastise me for being a critic. It is because of comments like these, bullshit is called on you:

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from TALONV8KILLER on 4:20 pm on Dec. 18, 2001
They have a 1.4 NA with 1500HP now so I think they could if they wanted to.
[/b][/quote]

TALONV8KILLER
December 20th, 2001, 05:03 PM
Loose-R just answer the question.
Do you agree that 4.0L 8cyl won't make double the power of a 2.0L 8cyl of the same design.

My car is fast because I made jump from 15.0 @ 97 mph to 12.55 @ 116.69.(On a stock block) My research and work!

If you spent more time learning about what you love critisizing you would know there are engines even more powerful than that Honda engine for they're size.

Stop being a critic and maybe contribute to the forum !

OH ya - answer the http://www.asianet.ca/images/iB_html/non-cgi/emoticons/confused.gif?http://www.asianet.ca/images/iB_html/non-cgi/emoticons/confused.gif

test
January 17th, 2002, 03:13 PM
Holy smokes this was good reading&#33;

Talonts96
January 17th, 2002, 07:33 PM
Wow.....more name calling...

Anyway, The more I think about it the more I think that the simple answer to the question is there is a replacement for displacment is a simple "yes" ....Its called a Turbo or a Supercharger. You put a Turbo or a supercharger on a lower displacement engine and you just soleved your displacement deficit. If youre comparing the exact same setup on both engines than its a different story.

Now onto the topic of double power on a identical internals one in a single inline four and one on a double in a V8 configuration. In theory you should be able to make double the power and a little bit.

First of all two identical inline 4 cylinder engines (I4) will produce double the power of one I4 engine. I think we all agree on that.

Hence, 1 head will generate half the frictional losses of two heads but also half the power is generated. So it all balances out on th top end. So the heads dont came to play.

Bottom end: the I4 cylinder has 5 mains and four rod bearings and 1 crank. The V8 arrangement has 1 crank (not two as in a seperate two engine setup) and less main bearings in total making less frictional losses than in the two seperate I4 engines. Frictional loss on the pistons on one v8 will be double than the I4 but again it will generate duble the hp.

Therefore the V8 should be able to produce double or slightly more than double of the I4. Simply because two I4 engines seperately will produce double the hp and the same engines sharing a common crank will induce less frictional losses than two seperate cranks. Of course all components being the same size and type. This is my oppinion anyways...Let me know if I&#39;m wrong....And if so educate me on why I&#39;m wrong.