:::RHMT::: Real Home Made Turbo
General Category => Hybrid/Tech => Topic started by: Atticus on May 09, 2009, 02:08:45 AM
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for the life of me i cant find a wright up with the thickness of the washer used on the over flow spring
some one help me out
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0.025-0.035
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why are you going to shim your pump?
waste of time
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ya, i know...turbod16. site sucks, but a decent write-up
http://www.turbod16.com/viewtopic.php?f=3&t=36600&st=0&sk=t&sd=a&start=0 (http://www.turbod16.com/viewtopic.php?f=3&t=36600&st=0&sk=t&sd=a&start=0)
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why are you going to shim your pump?
waste of time
im not going to argue with you about this again
ill do what i want
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actually we have never argued about it, ive just informed you of how its pointless. :yes:
thanks for helping me shoe-horn the motor in today :)
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Shimming the oil pump works. How well depends on your bearing clearances.
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Shimming the oil pump works. How well depends on your bearing clearances.
meaning the bigger the gaps + pressure = better?
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shimming the spring only increase the blow off relief pressure.
Yes, it works just like a blow off valve.
20 psi psi does nothing if your only making 14psi.
Does NOTHING for flow.
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the way i look at it
at 10 psi you have 10 cfm of flow. like a turbo
porting the pump reduces flow restrictions - like a bigger TB. lets say 12 cfm
but you still want more so you crank up the boost - 10 psi + 2 psi + porting = 14 cfm
that make sense?
Crittaz - you mean like a BOV leaking at 14 psi when your trying to run 20?
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You started asking about a washer/shim, but now talking about porting.
You voted for Obama right????
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You started asking about a washer/shim, but now talking about porting.
You voted for Obama right????
LOL
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reducing the flow restrictions of the oil pump ans passageways also decreases hp losses in the engine, all be it very small, it still counts
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You started asking about a washer/shim, but now talking about porting.
You voted for Obama right????
you must be fucking retarded to think i wouldn't port the pump
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Shimming the oil pump works. How well depends on your bearing clearances.
meaning the bigger the gaps + pressure = better?
shimming the spring only increase the blow off relief pressure.
Yes, it works just like a blow off valve.
20 psi psi does nothing if your only making 14psi.
Does NOTHING for flow.
simple. say you get 20psi at idle. so you shim your pump, fine. now you get 30, wow big difference. too fucking bad that you flow 75% less oil and starve your crank and/or topend of oil now.
how would you flow less with more pressure
its not a garden hose where you cover the tip to produce more pressure by sacrificing flow
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because tolerances only let you build up so much pressure aka backpressure. if you shim your shit for pressure, you reduce the amount of flow it will produce due to it not being able to build up as much oil in the tolerances with backpressure. it's pretty fuckin simple. why do you think air compressors produce 40cfm at 40psi, and only 18 at 90psi? the pump can only make x amount of pressure. your bearings, rods, cam, head etc dictate what holds the oil in the system. old worn out engines will see a gain in pressure, but really, how much more flow being built up does it take to reach that extra 10 psi that never gets used to effectively lubricate?
/beer rant
ok im convinced no shim for me :P
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Letting c0mpl3x convince you to do something is a sure sign of impending failure.
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Letting c0mpl3x convince you to do something is a sure sign of impending failure.
better then your vague ''Shimming the oil pump works. How well depends on your bearing clearances.'' statement
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If you shim your oil pump and match oiling holes of the main bearing with the block (size wise) you will see a slight difference oil pressure.
Follow this link on block prep, oil pump mods, and bearing mods and you will like the results.
Yes there is no shimming in this article but shimming the relief spring 0.025 to 0.035 does help. http://www.theoldone.com/articles/d_series_engine_building_tips/ (http://www.theoldone.com/articles/d_series_engine_building_tips/)
http://www.d-series.org/forums/diy-forum/94973-diy-oil-pump-shimming-porting.html (http://www.d-series.org/forums/diy-forum/94973-diy-oil-pump-shimming-porting.html)
I suggest 0.025 to 0.030 or take the existing gasket/shim for the cap for the oil releif spring assembly and grind it done to half of its thickness and that would do the same. ;D
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I'm allowed to be vague. This is simpler in operation than a wastegate, should be pretty obvious.
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Shimming the oil pump works. How well depends on your bearing clearances.
meaning the bigger the gaps + pressure = better?
shimming the spring only increase the blow off relief pressure.
Yes, it works just like a blow off valve.
20 psi psi does nothing if your only making 14psi.
Does NOTHING for flow.
simple. say you get 20psi at idle. so you shim your pump, fine. now you get 30, wow big difference. too fucking bad that you flow 75% less oil and starve your crank and/or topend of oil now.
how would you flow less with more pressure
its not a garden hose where you cover the tip to produce more pressure by sacrificing flow
because tolerances only let you build up so much pressure aka backpressure. if you shim your shit for pressure, you reduce the amount of flow it will produce due to it not being able to build up as much oil in the tolerances with backpressure. it's pretty fuckin simple. why do you think air compressors produce 40cfm at 40psi, and only 18 at 90psi? the pump can only make x amount of pressure. your bearings, rods, cam, head etc dictate what holds the oil in the system. old worn out engines will see a gain in pressure, but really, how much more flow being built up does it take to reach that extra 10 psi that never gets used to effectively lubricate?
/beer rant
theres no bypass in air compressors, bad example if you ask me
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theres no bypass in air compressors, bad example if you ask me
their flow drops as pressure increases. perfect example without getting over-complicated and explaining beyond that
but i WANT the complicated answer. the only reasoning for a drop in flow rate at a higher pressure that i can think of is that the flow transitions from laminar to turbulent and thus creates more back pressure
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Im glad this topic came up on here I was interested in doing it on my motor build but now Im not to sure...hmmm
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theres no bypass in air compressors, bad example if you ask me
their flow drops as pressure increases. perfect example without getting over-complicated and explaining beyond that
but i WANT the complicated answer. the only reasoning for a drop in flow rate at a higher pressure that i can think of is that the flow transitions from laminar to turbulent and thus creates more back pressure
i was referring to the air compressor flow vs psi rating, i wasn't at all bringing in any air compressor vs relief valves into the thread
your oil pump can only move x amount of oil at the given speed it moves at. start shimming the relief spring you will see higher oil pressure yes but the fact that it can only pump x amount of flow at the given speed it moves, it will have a reduction in volume output due to tolerances in the gear/body
sure you can shim it out to get 40-50psi but if you really had to shim it that much then get better tolerances elsewhere
it's a positive displacement pump. so what you're saying is that because you shim the by-pass, you therefore increase the amount of oil that 'sneaks' its way out of the rotors because its a higher back pressure (and oil pressure), and thus the oil pump doesn't move (flow) quite as much oil?
id love to see the actual numbers on that. i bet its not hardly measurable on an oil pump that has half ass decent tollerances.
Im glad this topic came up on here I was interested in doing it on my motor build but now Im not to sure...hmmm
(https://realhomemadeturbo.com/forum/proxy.php?request=http%3A%2F%2Fi91.photobucket.com%2Falbums%2Fk295%2Fonlyflash944%2FRed%2520CX%2FEngine%2FP1010266.jpg&hash=02eb90f8f94f5ee6e55ebddad0c8b283b4bf5359)
this shit's been in my build for 700 miles. no problems what so ever.
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theres no bypass in air compressors, bad example if you ask me
their flow drops as pressure increases. perfect example without getting over-complicated and explaining beyond that
but i WANT the complicated answer. the only reasoning for a drop in flow rate at a higher pressure that i can think of is that the flow transitions from laminar to turbulent and thus creates more back pressure
i was referring to the air compressor flow vs psi rating, i wasn't at all bringing in any air compressor vs relief valves into the thread
your oil pump can only move x amount of oil at the given speed it moves at. start shimming the relief spring you will see higher oil pressure yes but the fact that it can only pump x amount of flow at the given speed it moves, it will have a reduction in volume output due to tolerances in the gear/body
Uh, no. This isn't air we are talking about. Unlike air, oil is an incompressible fluid so the *only* factors that determine flow are the pressure, and the smallest orifice in the system. If there is any "backpressure" losses across oil pump rotor clearances then it manifests as a lower psi than you'd get if you calculated the affair out on paper.
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theres no bypass in air compressors, bad example if you ask me
their flow drops as pressure increases. perfect example without getting over-complicated and explaining beyond that
\
but i WANT the complicated answer. the only reasoning for a drop in flow rate at a higher pressure that i can think of is that the flow transitions from laminar to turbulent and thus creates more back pressure
i was referring to the air compressor flow vs psi rating, i wasn't at all bringing in any air compressor vs relief valves into the thread
your oil pump can only move x amount of oil at the given speed it moves at. start shimming the relief spring you will see higher oil pressure yes but the fact that it can only pump x amount of flow at the given speed it moves, it will have a reduction in volume output due to tolerances in the gear/body
Uh, no. This isn't air we are talking about. Unlike air, oil is an incompressible fluid so the *only* factors that determine flow are the pressure, and the smallest orifice in the system. If there is any "backpressure" losses across oil pump rotor clearances then it manifests as a lower psi than you'd get if you calculated the affair out on paper.
inconceivable
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Fuck Yooooooooouuuu!!!!
Now, back to Tazzy's point, the real trick is getting the oil pump to "spool" a little quicker. Since gearing is fixed you gotta change the system's VE. Just like having an engine within an engine.
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the way i'm reading things, either complex is right, or jd is
quite frankly, i don't give a shit cause it works both ways.
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A thunderdome battle will tell us who the winner is.
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two men enter
one man leaves
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Got money on masterblaster!!!! ;D
JK
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their flow drops as pressure increases. perfect example without getting over-complicated and explaining beyond that
so i was thinking about this, and i've figured out why it's wrong. flow drops as pressure increases is right, for air compressors. however, mass stays the same (or at least damn close). since air is compressible, the volumetric flow drops, but the mass flow should stay constant, within reason. thats why i don't see why shimming the oil pump to run at a higher pressure would cause a flow decrease in an incompressible fluid, such as oil.
rebuttal is welcome
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Exactly, compressable fluids are subject to VOLUMETRIC efficiency changes as their volume changes.