Not sure if anyone answered your question about a proper term for "flow" but I believe the term you are looking for is flux.
Oil Viscosity Effect On Oil Jet Cooling ....
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http://en.wikipedia.org/wiki/Volumetric_flow_rate
I guess I found it.
Volumetric Flow Rate (Q)
In short (probably) : Flow.
In my defence: the mentioning of "volume" is kinda important.
Now it all makes sense - to me.
Originally Posted By: Gary Allan
In a positive displacement situation, the flow dictates the rest of results. The pressure and velocity are products of flow ...determined by what it has to pass through/overcome in the process.
Now.. lets take 1 step back here and see: pump rpm dictates the volumetric flow rate (vfr from now on).
(correct terminology PLEASE!!! Haha!
)
In a positive displacement situation the pump rpm and vfr are in a fixed ratio (ideal fluid & pump).
Now add the viscosity of the fluid: lower viscosity generates lower pressure.
Now add the relief valve: lower pressure will allow higher pump rpm before it opens.
Higher pump rpm = more vfr.
End result: lower viscosity fluid = more vfr.
Shoot!
edit: I guess "we" allready reached this conclusion... as long as the relief actually opens at higher rpms.
Oh well...
Just use a 30 weight.
I guess I found it.
Volumetric Flow Rate (Q)
In short (probably) : Flow.
In my defence: the mentioning of "volume" is kinda important.
Now it all makes sense - to me.
Originally Posted By: Gary Allan
In a positive displacement situation, the flow dictates the rest of results. The pressure and velocity are products of flow ...determined by what it has to pass through/overcome in the process.
Now.. lets take 1 step back here and see: pump rpm dictates the volumetric flow rate (vfr from now on).
(correct terminology PLEASE!!! Haha!
In a positive displacement situation the pump rpm and vfr are in a fixed ratio (ideal fluid & pump).
Now add the viscosity of the fluid: lower viscosity generates lower pressure.
Now add the relief valve: lower pressure will allow higher pump rpm before it opens.
Higher pump rpm = more vfr.
End result: lower viscosity fluid = more vfr.
Shoot!
edit: I guess "we" allready reached this conclusion... as long as the relief actually opens at higher rpms.
Oh well...
Just use a 30 weight.
Last edited:
Originally Posted By: mechtech2
If Honda spent millions and could not figure out if the original oil jets were OK or not, how can any of us give an informed answer?
1)we are Bob Is The Oil Guy.
2) Amsoil will make it better
3) 0W-20 is the the best
If Honda spent millions and could not figure out if the original oil jets were OK or not, how can any of us give an informed answer?
1)we are Bob Is The Oil Guy.
2) Amsoil will make it better
3) 0W-20 is the the best
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Quote:
In a positive displacement situation the pump rpm and vfr are in a fixed ratio (ideal fluid & pump).
I guess
Quote:
Now add the viscosity of the fluid: lower viscosity generates lower pressure.
Yeeees (easing the Yeees in some anticipation type action)
Quote:
Now add the relief valve: lower pressure will allow higher pump rpm before it opens.
Yeeees (ditto - means "same")
Quote:
Higher pump rpm = more vfr.
Yeeees (ditto)
Quote:
End result: lower viscosity fluid = more vfr.
Maybe. It depends on if the relief level is ever met. Assuming it is ALWAYS met (at some point)..then AT THAT POINT and ABOVE ..YES, the lower viscosity fluid will flow more to the engine since less of it will be required to be relieved (shunted) to maintain the relief limit.
In a positive displacement situation the pump rpm and vfr are in a fixed ratio (ideal fluid & pump).
I guess
Quote:
Now add the viscosity of the fluid: lower viscosity generates lower pressure.
Yeeees (easing the Yeees in some anticipation type action)
Quote:
Now add the relief valve: lower pressure will allow higher pump rpm before it opens.
Yeeees (ditto - means "same")
Quote:
Higher pump rpm = more vfr.
Yeeees (ditto)
Quote:
End result: lower viscosity fluid = more vfr.
Maybe. It depends on if the relief level is ever met. Assuming it is ALWAYS met (at some point)..then AT THAT POINT and ABOVE ..YES, the lower viscosity fluid will flow more to the engine since less of it will be required to be relieved (shunted) to maintain the relief limit.
It seems that everyone agrees that there is less flow with a higher viscosity oil, but is it an inadequate flow? I mean if an oil with a 12.4 cSt (30wt) is ok, does that make an oil with a 12.6 cSt (40wt) unacceptable? It was brought up that Honda recommends a 5w-40 for cold weather areas... why not suggest a 5w30? Worldwide availability? Honda does not recommend against high performance driving while using 5w-40. Again I am just asking if anyone thinks that there is inadequate flow with a 40wt oil. Any thoughts?
Oh yea. Do piston squirters really make a spray pattern? Are you sure a straight stream doesn't shoot from each jet? I've seen dirty, and new turbine engine fuel injectors spray patterns. Seems like motor oil should be too thick to spray.
Hi,
IcebergS2000 - No! use a good quality 0W-40 lubricant if you wish
IcebergS2000 - No! use a good quality 0W-40 lubricant if you wish
Originally Posted By: SpitfireS
Well... Honda only recommends the 5W-40 for colder start-up temps.
In all other cases they recommend a 10w30.
That could mean dino is prefered, or either conventional or synthetic for cold climate because of course 5w-40 is synthetic.
Well... Honda only recommends the 5W-40 for colder start-up temps.
In all other cases they recommend a 10w30.
That could mean dino is prefered, or either conventional or synthetic for cold climate because of course 5w-40 is synthetic.
Originally Posted By: Gary Allan
It depends on if the relief level is ever met. Assuming it is ALWAYS met (at some point)..then AT THAT POINT and ABOVE ..YES, the lower viscosity fluid will flow more to the engine since less of it will be required to be relieved (shunted) to maintain the relief limit.
Given that the oil pressure rises to 125 psi @ 5000 crank rpm, I guess one can safely stop assuming the relief opens (at some point).
Given this engine has another crank 4000 rpm to go.
Originally Posted By: IcebergS2000
It seems that everyone agrees that there is less flow with a higher viscosity oil, but is it an inadequate flow? I mean if an oil with a 12.4 cSt (30wt) is ok, does that make an oil with a 12.6 cSt (40wt) unacceptable?
You're talking about GC.. aren't you?
In the oil world, there aren't that many borderline 30 weights.
No I don't think a 40 weight will be inadequate / unacceptable.
Its about having the choice.
Originally Posted By: IcebergS2000
It was brought up that Honda recommends a 5w-40 for cold weather areas... why not suggest a 5w30? Worldwide availability?
That would be the logical thing to do.
But Honda never changed the S2000 manual when it comes to engine oil. (and diff oil, brake fluid, MTF)
The 5W-40 recommendation is from 1999.
Its 2009.
It depends on if the relief level is ever met. Assuming it is ALWAYS met (at some point)..then AT THAT POINT and ABOVE ..YES, the lower viscosity fluid will flow more to the engine since less of it will be required to be relieved (shunted) to maintain the relief limit.
Given that the oil pressure rises to 125 psi @ 5000 crank rpm, I guess one can safely stop assuming the relief opens (at some point).
Given this engine has another crank 4000 rpm to go.
Originally Posted By: IcebergS2000
It seems that everyone agrees that there is less flow with a higher viscosity oil, but is it an inadequate flow? I mean if an oil with a 12.4 cSt (30wt) is ok, does that make an oil with a 12.6 cSt (40wt) unacceptable?
You're talking about GC.. aren't you?
In the oil world, there aren't that many borderline 30 weights.
No I don't think a 40 weight will be inadequate / unacceptable.
Its about having the choice.
Originally Posted By: IcebergS2000
It was brought up that Honda recommends a 5w-40 for cold weather areas... why not suggest a 5w30? Worldwide availability?
That would be the logical thing to do.
But Honda never changed the S2000 manual when it comes to engine oil. (and diff oil, brake fluid, MTF)
The 5W-40 recommendation is from 1999.
Its 2009.
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