SBC drysumpquestion
Discussion
I'm having trouble finding info about the need for the oiling of solid roller lifters
(Crower with highpressure pin oiling) by the splash through the holes in the liftervalley. Would like to close it of to avoid windage on the crank and scavange the liftervalley with the drysumppump.
Alternatively I could plug the holes with restrictors to give a little oil on the camshaft.
Oiling of the valvetrain is accomplished with forced oillines directly taken from the oilfeed, so I don't need oiling through the pushrods either.
I'm not looking for answers: "I would", "it should", but realworld facts and experience with the modification I'm looking for.
(Crower with highpressure pin oiling) by the splash through the holes in the liftervalley. Would like to close it of to avoid windage on the crank and scavange the liftervalley with the drysumppump.
Alternatively I could plug the holes with restrictors to give a little oil on the camshaft.
Oiling of the valvetrain is accomplished with forced oillines directly taken from the oilfeed, so I don't need oiling through the pushrods either.
I'm not looking for answers: "I would", "it should", but realworld facts and experience with the modification I'm looking for.
Solid roller lifters required less oil than others. I rebuilt my wet sump SBC last winter, using valley standpipes. As stated these allow breathing without oil windage. Also I put in oil restrictors in the back of the block, to reduce the oil flow to the lifters - all in the pursuit of more power.
If you are valve spring oiling Harry (via rocker covers or similar method and definite to do item for a revvy engine) there will still be some oil returning down the pushrod tubes so focus on getting the oil toward the rear of the valve chest area and scavenge out from there. Restrictor-standpipes set slightly higher than your scavenge port should be enough.
PS Isky damperless tool springs would be my choice combined with a titanium retainer.. if you use a damper with ti retainers, the damper soon starts to cut into the retainer causing associated debris and weakening.
rgds.
PS Isky damperless tool springs would be my choice combined with a titanium retainer.. if you use a damper with ti retainers, the damper soon starts to cut into the retainer causing associated debris and weakening.
rgds.
Edited by 738 driver on Friday 4th February 08:37
Thanks for the input.
I will shut them off then. Don't need the breathers, since I'm going to run with high vacuum with scavenging from bottom and topend.
I am using springoilers, but also want some oil to go through the pushrods, in order to oil the rockers.
I will shut them off then. Don't need the breathers, since I'm going to run with high vacuum with scavenging from bottom and topend.
I am using springoilers, but also want some oil to go through the pushrods, in order to oil the rockers.
Edited by harry b on Thursday 3rd February 20:52
You will need a four stage oil pump with one stage attached to a pipe that pulls oil from the rear of the lifter galley. The front is allowed to drain via the timing chain cover (SBC assumed here). The valley drains are plugged. Doubtful that you will ever notice the difference that results from the decreased windage but you will notice a difference when using a 4 stage pump rather than a 3, there won't be any oil leaks.
ken
ken
k wright said:
You will need a four stage oil pump with one stage attached to a pipe that pulls oil from the rear of the lifter galley. The front is allowed to drain via the timing chain cover (SBC assumed here). The valley drains are plugged. Doubtful that you will ever notice the difference that results from the decreased windage but you will notice a difference when using a 4 stage pump rather than a 3, there won't be any oil leaks.
ken
The need for a 4stage pump is known, a 3stage pump ain't an option. I also close off the drain through the timing valvecover since I'm using a Jesel timingbelt construction with zeroplay camshaft bearings. I only need a few drops to oil the needlebearings which hold the camshaft in place. They will get enough oil through the front cambearing.ken
Tests by others have shown that:
windage costs around 40HP.
Crankcase vacuum gains around 15HP.
Yes, you would think that the need for a four stage pump was well established, however if you order a motor from most builders and don't specify it I'll bet you end up on the phone looking to upgrade your pump. There are three stage pump sections that are extra wide that may be suitable.
The amount of oil that leaks down from the valve train is minimal if the rocker supply galleys are restricted.
Show us what you use to evacuate the valley.
ken
The amount of oil that leaks down from the valve train is minimal if the rocker supply galleys are restricted.
Show us what you use to evacuate the valley.
ken
Edited by k wright on Saturday 5th February 04:06
I would go 4 stage if committing to dry sump.....have two ex-US racer pumps.... Weaver and Dailey, both are 4 stage.
Vac/dry sump really only shines when associated components are employed in higher HP combo's and all else is optimized.... If its a street///occasional comp engine theres as much performance gain via improved torque/correct intake selection..... (you can lose a handfull of HP and gain three handfull's of torque with a well selected intake !!!)
Vac/dry sump really only shines when associated components are employed in higher HP combo's and all else is optimized.... If its a street///occasional comp engine theres as much performance gain via improved torque/correct intake selection..... (you can lose a handfull of HP and gain three handfull's of torque with a well selected intake !!!)
k wright said:
Yes, you would thing that the need for a four stage pump was well established, however if you order a motor from most builders and don't specify it I'll bet you end up on the phone looking to upgrade your pump. There are three stage pump sections that are extra wide that may be suitable.
The amount of oil that leaks down from the valve train is minimal if the rocker supply galleys are restricted.
Show us what you use to evacuate the valley.
ken
Then I'm happy that I'm building my engine myself.The amount of oil that leaks down from the valve train is minimal if the rocker supply galleys are restricted.
Show us what you use to evacuate the valley.
ken
The old engine had a three stage pump, so I need to buy another one.
738 driver said:
I would go 4 stage if committing to dry sump.....have two ex-US racer pumps.... Weaver and Dailey, both are 4 stage.
Vac/dry sump really only shines when associated components are employed in higher HP combo's and all else is optimized.... If its a street///occasional comp engine theres as much performance gain via improved torque/correct intake selection..... (you can lose a handfull of HP and gain three handfull's of torque with a well selected intake !!!)
ive just done a google search and cant see the known reasons for a 4 stage pump... Im sure mine is only 3 stage, should i be worried?Vac/dry sump really only shines when associated components are employed in higher HP combo's and all else is optimized.... If its a street///occasional comp engine theres as much performance gain via improved torque/correct intake selection..... (you can lose a handfull of HP and gain three handfull's of torque with a well selected intake !!!)
V8Dom said:
ive just done a google search and cant see the known reasons for a 4 stage pump... Im sure mine is only 3 stage, should i be worried?
No Dom no worries at all, I'm just looking for the max in the sbc. three stage is just fine, but in pursuit to the last bits of power you need to go for valley scavenging.With a three stage pump you won't be able to obtain high vacuum in the crankcase. All in all you can gain around 50HP, optimistic spoken. Even when you get around 20, it's always more than enough reason for Porsche, Ferrari or any topend brand to boast about 20HP gain in a new model. So why shouldn't I be doing that?? Will I ever notice it? Won't know, I've never driven an Ultima before. The thought behind it makes me want to do it.
Yes, you should ship it back to the seller and ask for a four stage pump. The other option is to allow the crankcase to vent to the atmosphere.
A typical 3 stage pump with one inch wide return sections will not generate enough vaccuum to pull the blow by from the crankcase at more than 4K RPM. As a result a crankcase that is not open to the atmosphere will leak oil everywhere no matter how good your gaskets are.
Options are to use a valley evaccuation tube as described above (easy to do with a Dart alloy block as there is a fitting at the back of the block), or to drill a large hole in the intake manifold that will allow an oil evacuation tube to pass through it.
You may also have two of your return stages on the pump joined (internal manifold) so that you can use a pan that only has two returns fitted and no valley return.
Another option is to use a pan that has 3 return fittings.
The last option is to use the three stage pump with only two return stages and vent the valve covers to atmosphere, the oil pressure should be fine. This is what I'm doing and the car has seen many track days. When needed I'll refresh the motor and change the system to allow for a valley return and add another return stage to the pump and seal the crankcase again.
If you need help you can call sales at Peterson dry sump systems: (303) 287-1731. They are a great resorce.
ken
A typical 3 stage pump with one inch wide return sections will not generate enough vaccuum to pull the blow by from the crankcase at more than 4K RPM. As a result a crankcase that is not open to the atmosphere will leak oil everywhere no matter how good your gaskets are.
Options are to use a valley evaccuation tube as described above (easy to do with a Dart alloy block as there is a fitting at the back of the block), or to drill a large hole in the intake manifold that will allow an oil evacuation tube to pass through it.
You may also have two of your return stages on the pump joined (internal manifold) so that you can use a pan that only has two returns fitted and no valley return.
Another option is to use a pan that has 3 return fittings.
The last option is to use the three stage pump with only two return stages and vent the valve covers to atmosphere, the oil pressure should be fine. This is what I'm doing and the car has seen many track days. When needed I'll refresh the motor and change the system to allow for a valley return and add another return stage to the pump and seal the crankcase again.
If you need help you can call sales at Peterson dry sump systems: (303) 287-1731. They are a great resorce.
ken
Edited by k wright on Monday 7th February 00:08
Edited by k wright on Monday 7th February 00:09
I would say that an engine isn't very well built or the pistonrings are beyond it's lifecycle when you need the fourth stage to eliminate the blow by.
Just a sideline connected to crankcase pressure.
From the old days, when we didn't have all the fancy tools, an engine was regarded in nice condition if you put the oilcap loosly on the valvecover, and it would rattle but not blown off when the engine is running. I think this probably works even today
Just a sideline connected to crankcase pressure.
From the old days, when we didn't have all the fancy tools, an engine was regarded in nice condition if you put the oilcap loosly on the valvecover, and it would rattle but not blown off when the engine is running. I think this probably works even today
k wright said:
It's a SBC, rev one up and it will need the extra volume.
Cheers!
What??!??!!???? What are you telling me now, I've got an "all american" piece of iron that will be puffing and hissing like an old steamloc??? Cheers!
Bummer! Ahh...... well at least it's been built european style.
(hiding under the table for the response)
Harry, you are going to have some fun along this road !
Yes they do huff n puff a bit at first but with care will soon settle down.
RE the dry sump, if you fit lower tension rings, have a first class honing job and aftermarket block, gas ported pots, max oil control work and 100% tolerances you will see big HP increases especially on the engine dyno. In the chassis this might be a little less. A properly specced road-race SBC needs lots of oil around the top end to live and lots of evacuation to avoid windgage, leaks etc.
An ex factory block is unlikely to have bores that are consistent enough to fully gain the benefits (cylinder wall deflection at higher cylinder pressures). Might be best to accept some slight losses, incorporate gapless rings and just pull as much vac as you can.
PM's Dom/Harry with a tip.
Yes they do huff n puff a bit at first but with care will soon settle down.
RE the dry sump, if you fit lower tension rings, have a first class honing job and aftermarket block, gas ported pots, max oil control work and 100% tolerances you will see big HP increases especially on the engine dyno. In the chassis this might be a little less. A properly specced road-race SBC needs lots of oil around the top end to live and lots of evacuation to avoid windgage, leaks etc.
An ex factory block is unlikely to have bores that are consistent enough to fully gain the benefits (cylinder wall deflection at higher cylinder pressures). Might be best to accept some slight losses, incorporate gapless rings and just pull as much vac as you can.
PM's Dom/Harry with a tip.
I was just fooling around.
My engine specs ain't normal stock:
Bowtie 24502503 CNC block
TRW pistons with Total seal rings,
Steel forged crankshaft with H-beam rods,
Brodix proted heads to match Hillborn 2 1/2" throttle bodies,
Crower special camshaft, crower t-bar roller lifters with pin oiling, crower 1:1.5 roller rockers,
Milodon sst racing valves dual valvesprings with dampers, valve spring oilers, SCE titan headgaskets with sealing wire,
Jesel camshaft beltdrive with zeroplay thrustbearings, ATI racing damper, etc, etc, etc.
My engine specs ain't normal stock:
Bowtie 24502503 CNC block
TRW pistons with Total seal rings,
Steel forged crankshaft with H-beam rods,
Brodix proted heads to match Hillborn 2 1/2" throttle bodies,
Crower special camshaft, crower t-bar roller lifters with pin oiling, crower 1:1.5 roller rockers,
Milodon sst racing valves dual valvesprings with dampers, valve spring oilers, SCE titan headgaskets with sealing wire,
Jesel camshaft beltdrive with zeroplay thrustbearings, ATI racing damper, etc, etc, etc.
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