<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Lsos &raquo;</TD></TR><TR><TD CLASS="quote">

Stiffer valve springs won't increase torque. In fact, they might actually decrease it due to increased friction.

They do however allow you to run bigger cams, among other things, and those might increase torque.</TD></TR></TABLE>

Friction is a different force not related to torque. To suggest that would open room to say that a better engine oil that reduces friction in the components will give you higher torque.
Case in point:

96 spec R and the 98 spec R 18.5 kg/m up to 19.0 kg/m

Bottom end is identicle Cams are the same So what's different? Valves Springs
are stiffer.
Spoon also claims there will be a rise in torque with the use of their springs. I have seen it in other applications in the past where the torque is increased. I mean you're not talking about a huge rise in torque just like a 1/2 of Kg/m

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">Gotta re-arrange the parentheses there...

CR = (Vc + disp) / Vc
where:
disp = displacement = pi*(bore/2)^2 * stroke
Vc = your 'compressed volume' which includes combustion chamber volume corrected by headgasket & piston features.</TD></TR></TABLE>

The equation is correct, but the term [compressed volume] is misleading. My [compresed volume] only includes the added "heights" of the cylinder wall. It is not until they are multipled against the surface area that they become a volume.

Edit: changed to [compressed height].

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">While the original question was probably about 'how can I get more torque', I was trying to clarify some stuff that sounded like smoke & mirrors. There's a lot of technical jargon being used by people without a physics background. I guess instead of saying 'that's dumb' I wanted to try & explain some of it.
</TD></TR></TABLE>

I applaud any attempt to get a technical discussion out of any thread, and I personally look for chances to create one, whether the original poster wanted one or not. Here's another thread "that was supposed to be a simple question" that kinda exploded: https://honda-tech.com/zero...age=3.


Modified by GSpeedR at 8:31 PM 8/22/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">Friction is a different force not related to torque. To suggest that would open room to say that a better engine oil that reduces friction in the components will give you higher torque.</TD></TR></TABLE>

Though negligible, if the crank did not have to turn through a viscous fluid, it would indeed produce more torque (so I would agree with that). The viscous force opposes the proper crank rotation. Unfortunately, to keep things at optimal temperature and to avoid complete metal-metal contact, the engine needs it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Bottom end is identicle Cams are the same So what's different? Valves Springs
are stiffer.
Spoon also claims there will be a rise in torque with the use of their springs. I have seen it in other applications in the past where the torque is increased. I mean you're not talking about a huge rise in torque just like a 1/2 of Kg/m</TD></TR></TABLE>

I also can't visualize how stiffer springs increase torque. If anything, the fact that it takes more force to compress the spring the same distance (and the valve will still open the same amount ) would mean more force from the spring on the rocker arm/follower, which does indeed mean more friction. I thought that they're only benefit was the needed strength at higher rpm, and the fact that the valves can be held open longer since these springs will close it faster.



Modified by GSpeedR at 8:29 PM 8/22/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">Friction is a different force not related to torque. To suggest that would open room to say that a better engine oil that reduces friction in the components will give you higher torque.
</TD></TR></TABLE>

While the engine might attempt to produce the same amount of torque, the more friction inside it, the more torque is used up countering that friction, and the less torque ends up at the flywheel.

There is plently of room to say that better engine oil will give you more torque. Try draining the oil in your engine and replace it with sand, and then dyno the thing. I can guarantee the engine with the better "oil" will produce more torque. Eventually the engine with the sand will seize up, effectively making the friction infinite and the torque output will be zero.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">Bottom end is identicle Cams are the same So what's different? Valves Springs
are stiffer.
Spoon also claims there will be a rise in torque with the use of their springs. I have seen it in other applications in the past where the torque is increased. I mean you're not talking about a huge rise in torque just like a 1/2 of Kg/m</TD></TR></TABLE>

Until someone gives me an explanation for why stiffer valve springs would increase torque, I will not believe it. I don't believe Spoon's claims on this, as well as other people's. Something else has to have changed...cams, timing, compression...something.

 

I usually think about friction like this: The engine produces 'some' amount of torque, but part of it is used up overcoming internal friction. The part that gets used up on internal friction is never measured in the first place.

I'm also confused about HOW stiffer valve springs increase torque. I'd be real interested to learn about that. Seems like they would increase friction between the camshaft & the follower. Period. The valves will open the same amount, because the springs still aren't stiff enough to bend the camshaft.

Stiffer valve springs are one thing that's needed if you want to rev higher than the factory redline. So my GS-R must already have stiffer valvesprings compared to, say, my lawnmower. In order to take advantage of that 'feature' you need a different camshaft.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">
96 spec R and the 98 spec R 18.5 kg/m up to 19.0 kg/m

Bottom end is identicle Cams are the same So what's different? Valves Springs
are stiffer.</TD></TR></TABLE>

Surely this difference could ber down to the different exhaust manufold used in the later models? Also are the ECU programs identicle between the 96 and 98 model? Could not fueling and timing changes could acount for it also?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GSpeedR &raquo;</TD></TR><TR><TD CLASS="quote">

Assuming that the pressure stays the same, we will increase the force simply by increasing the surface area. However, since the compression doesn't stay the same, but actually increases a little (I had to find the C-ratio formula to check that), force will increase more, though (correct me if I'm wrong here) not a whole lot. The fact that the piston area has a larger surface area multiplies the force to a greater extent than the fact that the compression ratio has changed.

Force = Pressure*(bore/2) ...very simple forumla...

C-ratio = Pi*(bore/2)^2*((stroke + [compressed height])/[compressed height])

The term [compressed volume] includes head gasket thickness, added deck height combustion chamber, and piston top volume.

So a 1 mm increase in bore yeilds a 0.5 increase in force (units?).

So a 1 mm increase in bore yeilds a 0.25 increase in compression ratio.

I haven't gone through to attempt to figure out how the increase in compression is related to the force at the piston (I'm sure it depends on a LOT), but large increases in bore greatly increase C-ratio (ratio increases with the square of the cylinder radius rather than linearly as in the "force"). To save me the trouble, has anyone figured this out? Or am I missing something big?
Modified by GSpeedR at 2:37 PM 8/22/2003</TD></TR></TABLE>

are you sure the CR increases when simply boring out an engine? In what you described, keeping the pressure the same, you assume that the CR will increase.

if you bore it out, you increase the volume of the chamber, and so if you set the amount of air+fuel that is injested as constant instead of pressure, I think boring out an engine would reduce the pressure since the given amount of fuel+air has a larger volume to occupy, and thus the pressure is lower when boring out than before doing so. However the increased surface area of the piston does counter-balances the pressure loss:

force = pressure * SA (lets assume a flat flat piston, not domed or anything so SA is just the area of the face of a circular piston).

Yes you can counter the pressure drop if you are able to raise the compression ratio, but does boring it out automatically increase the CR? Like if you were to use a flat faced piston in an engine, you have a given CR. Then you bore it out and use a slightly larger flat faced piston, and keeping all else equal so you only injest a set constant amount of air, does the CR really increase? or decrease?

I'm thinking the pressure and CR will decrease if you simply bore it out and keep all else the same (amount of air+ fuel used). If you allow it to increase the amount of injested air proportional to the amount of displacement you added by boring, I'm thinkign the CR would then be the same as the original in that case? This is of course assuming all else equal like friction,etc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TypeSH &raquo;</TD></TR><TR><TD CLASS="quote">

are you sure the CR increases when simply boring out an engine? In what you described, keeping the pressure the same, you assume that the CR will increase.

if you bore it out, you increase the volume of the chamber, and so if you set the amount of air+fuel that is injested as constant instead of pressure, I think boring out an engine would reduce the pressure since the given amount of fuel+air has a larger volume to occupy, and thus the pressure is lower when boring out than before doing so. However the increased surface area of the piston does counter-balances the pressure loss:

force = pressure * SA (lets assume a flat flat piston, not domed or anything so SA is just the area of the face of a circular piston).

Yes you can counter the pressure drop if you are able to raise the compression ratio, but does boring it out automatically increase the CR? Like if you were to use a flat faced piston in an engine, you have a given CR. Then you bore it out and use a slightly larger flat faced piston, and keeping all else equal so you only injest a set constant amount of air, does the CR really increase? or decrease?

I'm thinking the pressure and CR will decrease if you simply bore it out and keep all else the same (amount of air+ fuel used). If you allow it to increase the amount of injested air proportional to the amount of displacement you added by boring, I'm thinkign the CR would then be the same as the original in that case? This is of course assuming all else equal like friction,etc.</TD></TR></TABLE>


Yes, having a bigger bore, all else the same will increase your CR cuz you increased sweept (spel?) volume, yes, you also increased the volume of the chamber, but you also increased sweept volume by a lot.

Go to this thread, is an excelent thread to learn about it. https://honda-tech.com/zerothread?id=573765


and CREATOR!: you can pretty much reduce the options you have to
A) increase stroke
B) increase pressure: Bigger compression, more efficiency, higher air flow, colder air, colder fuel, more timming, keep the heat into the CC (coatings and all that stuff), if you want torque down low you need to read about backpressure a lot and if you don't care about torque down low but you need HP on high RPM a free flowing exhaust will do, but remember to get the best efficiency (better torque) you have to keep in mind the flow of air in the engine.

BTW: stiffer valve springs won't do nothing for torque, but you have to realize that little details that one might not realize can help you get stuff like that, like a better port&polish jobs, different ECU, better sensors, better oil flow, etc... also remember that not all engines are the same, you can have two engines being the same engine made the same year, made the same date but one can have more TQ or HP more than the other. things are like that in this world which makes it interesting, IMHO

Great thread

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TypeSH &raquo;</TD></TR><TR><TD CLASS="quote">if you bore it out, you increase the volume of the chamber, and so if you set the amount of air+fuel that is injested as constant instead of pressure, I think boring out an engine would reduce the pressure since the given amount of fuel+air has a larger volume to occupy, and thus the pressure is lower when boring out than before doing so. However the increased surface area of the piston does counter-balances the pressure loss:

force = pressure * SA (lets assume a flat flat piston, not domed or anything so SA is just the area of the face of a circular piston).</TD></TR></TABLE>

This is also what I thought. I did a little research and realized that you can't consider the induction of air in the cylinder as a simple "enclosed gas" model. GZero, mentioned this, and from a general physics/chem perspective, it is counter-intuitive.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Yes you can counter the pressure drop if you are able to raise the compression ratio, but does boring it out automatically increase the CR? Like if you were to use a flat faced piston in an engine, you have a given CR. Then you bore it out and use a slightly larger flat faced piston, and keeping all else equal so you only injest a set constant amount of air, does the CR really increase? or decrease?</TD></TR></TABLE>

The swept volume is essentially the displacement for 1 cylinder. Since C-R ratio is calculated by the equation C-Ratio = (Swept Volume + Cylinder Head Volume)/Cylinder Head Volume

Increasing the bore increases the swept volume and the cylinder head volume. Add 1 to x and y in the formula C/R = (x + y)/y and you'll end up with something larger than what you started with.

GZERO: Thanks for the thread.

 

Sand in the ENGINE??? LOL Let's try and keep this discussion REAL. My point was to say that if one uses a different thinckness of oil then it would change the output of the engine. Using a 10w-30 Conventional compared to using a 5w-30 Synth would yeild a change in "torque" according to your theory. I am not saying that Friction has no effect on the SySTEM, but I don't think that Stiffer Springs will take away torque. So in this case do you think micro polishing the drive axel bearings will add more torque??

I have already explained that I can't explain how it has an effect but I personally have observed this effect. I have heard it from other places as well.

True there are other factors that could explain the Slight increase in torque, But in reading a book about the differences between the 96 spec and 98 spec it credited the torque Rise to the changes in the valve train.
Although the Springs ar harder to compress they push back with just as much force. It's not a one way street.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">Sand in the ENGINE??? LOL Let's try and keep this discussion REAL. My point was to say that if one uses a different thinckness of oil then it would change the output of the engine. Using a 10w-30 Conventional compared to using a 5w-30 Synth would yeild a change in "torque" according to your theory. I am not saying that Friction has no effect on the SySTEM, but I don't think that Stiffer Springs will take away torque. So in this case do you think micro polishing the drive axel bearings will add more torque??</TD></TR></TABLE>That example doesn't have much of a difference. Without getting into details of viscosity vs. temperature and viscosity changes with time/temperature history, 10w-30 and 5w-30 have the same viscosity at operating temperature. The 10w & 5w are the cold-viscosity, but they're both '30-weight' once they're hot. How about 10w-30 vs. 90-weight oil?

In my mind(?) micropolishing drive axle bearings doesn't add torque, but it reduces the amound of driveline drag. Kinda like fixing a dragging brake caliper. An engine dyno wouldn't see any change, but a chassis dyno would.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">True there are other factors that could explain the Slight increase in torque, But in reading a book about the differences between the 96 spec and 98 spec it credited the torque Rise to the changes in the valve train.
Although the Springs ar harder to compress they push back with just as much force. It's not a one way street.</TD></TR></TABLE>Changes in the valve train encompass more than just springs. Are the ports shaped differently? Camshafts? Valves? I don't know what else is different, but for the small change it wouldn't take much.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoond TEG &raquo;</TD></TR><TR><TD CLASS="quote">Sand in the ENGINE??? LOL Let's try and keep this discussion REAL.</TD></TR></TABLE>

My point is that all else equal the more friction in the engine, the less torque output there will be. I think my extreme example showed this very clearly. Whether you are actually going to put sand in your engine or not is irrelevant.

 

I just had to revive it.