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raygreenwood
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Joined: November 24, 2008
Posts: 21512
Location: Oklahoma City
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 Posted: Tue Jun 15, 2021 12:36 pm Post subject: Re: Interesting oil pressure issue |
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| evanfrucht wrote: |
| Keith Park wrote: |
Well I ran the same hill, same speed, same weather, but with the head vents plugged where they went into the air cleaner,
And Walla! NO loss in oil pressure!
Ok, this tells us something, but should I try a restrictor in that hose or something else?? |
The crankcase is not breathing properly... cavitation is occurring... |
Yes.....this.....but its backwards from what you might think.
As previouslh noted....this PCV system pulls air INTO the rocker boxes.....through the PR tubes.... and into the case.....and out the top of the case via manifold vacuum.
Its one of the things I speculated a couple posts back.
So.....on a long hill at high rpm....these two things happen at various levels.
1. The high rpm like on many ACVW....fills one valve cover with oil....or tries to. The D-jet type 4 PCV system is REALLY good at stopping this.....because the venting pushes oil out of the PR tubes into the case. It keeps the rocker boxes very clean.
2. At an angle.....all excess oil is going to flow rearward so you have a good bit pooled up around the #2 and 4 crank throws .......and.....one important thing to remember............... you noted that you did some judicious drilling/adding of drainback holes to the stock windage tray.
I bet you did them close to the center near the cam like Jake Raby and others have described....right? Which is usually good!....probably for level ground.
The smaller problem is that the PR tubes dump their oil back on TOP of the windage tray. This is why you drill extra holes to get that oil back into the pan under the tray before the camshaft whips it up.
But......those holes are under the cam?.....a straight shot across from the PR tubes?
When the car is at an up or down hill angle..... the oil in the rocker boxes whether its excessive or not.....is not flowing ACROSS to those holes. Its flowing fearward toward the pulley or forward toward the flywheel.....and into the already big puddle getting whipped by the rods and crank throws.
So in reality.....Ohio Tom was right....it IS oil foaming.....but not by itself.
So....blocking off the PCV means that just enough oil is being kept from feeding the big puddle.......OR...... its an excessive amount of PCV inlet air thst may be causing actual frothing at the PR tube outlets.
Try this now. Replace the 3mm orifice with a 1.5mm orifice.
It will still be PLENTY of PCV because its a constant instead of random pulse.
Be careful. Reducing a constant vacuum leak like that WILL deop your idle and make mixture slightly leaner.
Ray |
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Keith Park
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Joined: August 13, 2006
Posts: 225
Location: Clifton Park NY
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| Posted: Tue Jun 15, 2021 5:56 pm Post subject: Re: Interesting oil pressure issue |
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well this is a Raby kit, and Jake uses nothing but the DT50 in these in the summer months, its specifically designed for this application and if there were problems with it he wouldnt use it.
So how to modify the breather... the heads breathe basically the stock 914 way, my air filter is of course different and it dumps between the K&N and the throttle body, the breather box goes right to the intake air distributor, with the 3mm restrictor in it.
Ill try the 1.5mm, im still fine tuning the mixture so thanks for the reminder...
Yes the cutouts in the windage tray are in the middle, if I recall right I hogged out the dips in the tray along the edges, I have a picture somewhere.
Keith |
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raygreenwood
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Joined: November 24, 2008
Posts: 21512
Location: Oklahoma City
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| Posted: Tue Jun 15, 2021 7:45 pm Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
well this is a Raby kit, and Jake uses nothing but the DT50 in these in the summer months, its specifically designed for this application and if there were problems with it he wouldnt use it.
So how to modify the breather... the heads breathe basically the stock 914 way, my air filter is of course different and it dumps between the K&N and the throttle body, the breather box goes right to the intake air distributor, with the 3mm restrictor in it.
Ill try the 1.5mm, im still fine tuning the mixture so thanks for the reminder...
Yes the cutouts in the windage tray are in the middle, if I recall right I hogged out the dips in the tray along the edges, I have a picture somewhere.
Keith |
I am thinking you have done everything right that you can. What little I know about Jakes windage tray mods...others have done and they make sense and work well.
In my experience.....the windage tray does its best work keeping the oil slosh under control from front to back. Not saying it does not do well side to side...but you get so much side to side "sling" anyway......as Jake found ...and others...the biggest issue with the stock tray...is NOT controlling whats underneath it...its controlling the return oil from the PR tubes that is on top of it.
At a slant...uphill....it kind of bypasses the whole thing right?
Not suggesting you change oil at all. I get where Ohio Tom is coming from....but if you are only getting foaming/frothing under thie ONE CONDITION....then its mechanical and not oil related.
The 3mm orifice...works great for "most" stock 411/412/914......1.7L. Yours is NOT stock....or a 1.7L. I have no idea what kind of vacuum you or pulling or how little or how much cases gasses you generate.
Try the 1.5mm....see what you get. Its just tuning right? 
Ray |
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Keith Park
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Posts: 225
Location: Clifton Park NY
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| Posted: Wed Jun 16, 2021 6:53 pm Post subject: Re: Interesting oil pressure issue |
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Not the first time ive been reminded in NOT stock! 
Well I got the 1.5mm in there, but it will be another 10 days or so before I hit the hill again. boy thats a small hole, if I didnt know any better id consider it "Clogged" 
the first build of this engine didnt have the windage tray or the tuna can, and I had a HUGE problem of sucking the sump dry on long sweeping highway bends, id even get an oil light! So I hogged the tray out and installed the tuna can, that solved THAT problem, but one additional thing to note is that adding an extra half quart of oil to my current situation did NOT change anything.
Thanks,
Keith |
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Clatter
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Joined: September 24, 2003
Posts: 7537
Location: Santa Cruz
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| Posted: Wed Jun 16, 2021 7:12 pm Post subject: Re: Interesting oil pressure issue |
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How have i missed this car for so long?
Got a thread for it?
As a fellow owner of a type4 in a type3,
I'd really like to see your windage tray mods.
_________________
Bus Motor Build
What’s That Noise?!? |
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Keith Park
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Joined: August 13, 2006
Posts: 225
Location: Clifton Park NY
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| Posted: Wed Jun 16, 2021 7:44 pm Post subject: Re: Interesting oil pressure issue |
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Here is a photo of the windage tray with mods, in case, you can see the rectangular cutouts in the middle. Hopefully this upload works but the photo is in the 914 gallery.
Keith |
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raygreenwood
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Joined: November 24, 2008
Posts: 21512
Location: Oklahoma City
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| Posted: Wed Jun 16, 2021 10:03 pm Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
Here is a photo of the windage tray with mods, in case, you can see the rectangular cutouts in the middle. Hopefully this upload works but the photo is in the 914 gallery.
Keith |
Man...I think those "windows" under the cam may be too big. I think you may be getting a rearward slosh.....but I will not sign on to that yet....because its JUST too odd....that plugging off the vents stopped it. I think you are "frothing" the oil at the ends of the pushrod tubes from excess PCV.
Pure speculation on my part.....but we have one data point. Lets see where it goes.
Back when I started the "fixed" orifice PCV valve....I chose 3mm...because it was easy to make accurately....and not too hard to adjust around the extra air effect on the MPS. The MPS had plenty of adjustment capability. I did this on several engines.
But....later ...a few people IIRC...over in the STF using the same technique found that 3mm was a little too much. I cannot remember how far different from stck or whether they were 2.0L 914...which has the same MPS baseline as 1.7L but a different full load plate calibration.....but they found that 2.0 to 2.5mm....worked better for them.
It might work better for you too. But.....bear in mind...the little plate in the stock PCV was abut 12mm diameter. When it lifts it lifts by one edge....maybe .001" to .003"...so it only opens a little wedge shaped crescent moon. Very small area. The area of a 3mm orifice is actually larger than that.
The other issue is that when you are sucking through small orifices....you get turbulence...they can "choke" flow. You can make changes by chamfering one or both ends to affect how air behaves and moves away from the orifice once it squeezes through it...but that a lot of experimenting.
I noted to go to 1.5mm....because its a major change ...right in between "0" and 3  . If "0" fixed the problem...and 3.0 shows the problem.....its just easy money to see what right in the middle does.
Ray |
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Keith Park
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Posts: 225
Location: Clifton Park NY
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| Posted: Thu Jun 17, 2021 10:35 am Post subject: Re: Interesting oil pressure issue |
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Well those windows fixed the oil starvation issue and its not a problem around corners now either... im sure the tuna can is part of that too.
One thing maybe I didnt make clear, when I tested the car on the hill the the ventilation plugged, I only plugged the line FROM THE HEADS, thats a separate system that goes thru the flame arrester to the air cleaner elbow. I left the breather box to intake air distributor intact with the 3mm. This is how the hose diagram showed it set up on the 914 2L, 2 separate systems.
Keith |
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raygreenwood
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Joined: November 24, 2008
Posts: 21512
Location: Oklahoma City
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| Posted: Thu Jun 17, 2021 11:10 am Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
Well those windows fixed the oil starvation issue and its not a problem around corners now either... im sure the tuna can is part of that too.
One thing maybe I didnt make clear, when I tested the car on the hill the the ventilation plugged, I only plugged the line FROM THE HEADS, thats a separate system that goes thru the flame arrester to the air cleaner elbow. I left the breather box to intake air distributor intact with the 3mm. This is how the hose diagram showed it set up on the 914 2L, 2 separate systems.
Keith |
Yep...I get that ...but No....that IS all the same system. Its not two systems. You simply separated it into two systems
What you did when you disconnected/plugged the heads .....is you simply blocked off the "flow through" portion of this system.
So...the way you set this up when you plugged the vents from the heads....is that the line from the oil breather with the 3mm restrictor.... is still sucking any out blow-by gases in the case.....when they become available....but now its no longer sucking air into the rocker boxes .......and then through the pushrod tubes...and into the case.
So...you still have "basic" PCV with that line and 3mm restrictor connected.....but you simply no longer have a ton of air flowing through the rocker boxes and out of the PR tubes into the case.
The PCV systems for 914 and 411/412 are identical. Its a really good system. It keeps the engine very clean with very little baked on sludge as log as you keep your oil changed. The upper oil baffle box works very well with this system ....but far above stock....I just don't know how well the airflow is balanced....which is what I "think" is happening to you.
Realize this....I have to sit down and calculate vacuum versus pressure....but your 3mm (0.118") orifice...lets say you made it out of a piece of plastic or aluminum round bar 0.5" long with a 3mm hole drilled through it....but just with pressure and not vacuum.....that hole just with 5 psi ...flows 3.00 cubic feet per minute.
Thats just a tubing and air pressure calculation. At any given time pulling say....10" of vacuum at that port to the manifold.....wait...found it....REALLY nice chart!.....its about half for vacuum (0.491" HG to each psi or pressure equivalent).....but the vacuum at that 12mm hose to the oil box is pretty high all the time. You should check vacuum there if you have time to see what you are getting.
These things idle at about 10-12" vacuum at that port. You could be running 15" easy at that port at high throttle.
So....lets say its high vacuum....and teh higher compression and port velocity in these things the higher the plenum vacuum you will get.....30 cubic feet per minute SCFM....meaning..."standard cubic feet per minute.....which means its compared to a standard or reference......so if your STANDARD....which would mean local atmospheric pressure.....is changing or low.....you could get even HIGHER "CFM" flow rates.
So using a caluclator I found...plugging in barometric for say 30 in Clifton pk NY, temperature of 72...relative humidity of 40%.....and dividing pressure by half to get ~vacuum.....I see upwards to 12.25 cfm possible through those rocker boxes....divide by two...about 6.0 each.
Thats a lot of airflow.
Ray |
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Keith Park
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Location: Clifton Park NY
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| Posted: Thu Jun 17, 2021 6:37 pm Post subject: Re: Interesting oil pressure issue |
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Very interesting. yea, alot of air!
Ok, next run will be with the 1.5mm and head vents reconnected. Ill let you know
Thanks
Keith |
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Keith Park
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Location: Clifton Park NY
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| Posted: Thu Jun 24, 2021 7:16 pm Post subject: Re: Interesting oil pressure issue |
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OK, 1.5mm in there pulled the same hill and its significantly worse, OP dropped into the upper 20's briefly before I backed off. I was however towing a small trailer so the hammer was down a bit harder than usual but its definately worse.
should I try a larger restriction? or what about putting a restriction in the line from the heads to the air cleaner, when that was plugged the oil issue went away.
Thoughts?
Thanks'
KEith |
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raygreenwood
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Posts: 21512
Location: Oklahoma City
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| Posted: Thu Jun 24, 2021 7:37 pm Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
OK, 1.5mm in there pulled the same hill and its significantly worse, OP dropped into the upper 20's briefly before I backed off. I was however towing a small trailer so the hammer was down a bit harder than usual but its definately worse.
should I try a larger restriction? or what about putting a restriction in the line from the heads to the air cleaner, when that was plugged the oil issue went away.
Thoughts?
Thanks'
KEith |
Not ignoring you. This is all good data. I need to think about what "could" be happening that employs the PCV system and the heads.....and not just general oil foaming. If it were that....you would get it anytime you were in that rpm range.
So...the things we know....
1. at moderate to high rpm....on an upward incline
2. You can turn off the problem by BLOCKING...pull through PCV. Not ALL PCV...just the pull through the heads and PR tubes.
3. Smaller restriction makes it worse.
NOTE: be sure of that. Try that last one again making sure ambient temp is similar and with no trailer. Reason.....because out of the ordinary or higher than normal temps may be part of the equation of making it worse.
Make sure each test run is as similar as possible.
Ray
Hmmmmmm |
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Keith Park
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Location: Clifton Park NY
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| Posted: Fri Jun 25, 2021 7:27 pm Post subject: Re: Interesting oil pressure issue |
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Well next week Im pulling the boat up, so it may be the week after but Ill get that data point with the 1.5mm one in there, no trailer, yea it was 80 that day so not hot but good and warm, oil temps were a bit higher than before.
thanks
Keith |
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Keith Park
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Location: Clifton Park NY
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| Posted: Sun Jul 04, 2021 7:20 pm Post subject: Re: Interesting oil pressure issue |
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another data point, although this one I wish i hadnt got!
pulling the boat up to the lake, so it got a good load on it, even put it in 3rd on the big hill for just a bit, I had though I had restricted the flow from the heads again as I didnt want it to have OP issues with the load but I screwed up and the vice grips on the hose had indeed plugged it off totally, and although there was no oil pressure issues I ended up with oil blown out all over the back of the engine and into the fan.
it sure does need the head vents, at least when its running hard! Im not sure where the oil found its way out but Im hoping I didnt blow the rear main seal out, the oil is in the fan. Ill have to see what happens driving it home without the boat and the flow returned. the level is still near full so I dont think I lost alot but... a mess!
KEith |
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raygreenwood
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Location: Oklahoma City
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| Posted: Mon Jul 05, 2021 11:27 am Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
another data point, although this one I wish i hadnt got!
pulling the boat up to the lake, so it got a good load on it, even put it in 3rd on the big hill for just a bit, I had though I had restricted the flow from the heads again as I didnt want it to have OP issues with the load but I screwed up and the vice grips on the hose had indeed plugged it off totally, and although there was no oil pressure issues I ended up with oil blown out all over the back of the engine and into the fan.
it sure does need the head vents, at least when its running hard! Im not sure where the oil found its way out but Im hoping I didnt blow the rear main seal out, the oil is in the fan. Ill have to see what happens driving it home without the boat and the flow returned. the level is still near full so I dont think I lost alot but... a mess!
KEith |
Ok...lets look at a couple of things:
1. In general...meaning for now...in your past test....plugging the head vent hoses.....which keeps air from ENTERING the case...because it vents through manifold vacuum at the top......which stopped the OP loss from happening.
2. WE know the type 4 engine is no different than a type 1 in the respect that it puts a lot of oil in the rocker box on one side when running.
The difference with type 4's using this particular case venting system (4411/412/914's)....the flow through rocker box vent system keeps most of that oil out of the rocker boxes. It pulls it right through the PR tubes into the case at a higher rate.
3. So....if you plug the rocker vents...no more flow through and you will have more oil collecting in the rocker boxes.....you have less oil pooling in the rearward side of the case on an incline....and getting whipped up by the #2 and #4 crank throws and rods............
So....this time ....just like last time when you plugged the head vent hoses....you got no OP loss because the big pile of oil at the rear of the case was not getting whipped by #2 and #4.
I think Ohio Tom was correct that the ROOT CAUSE of the oil pressure loss was oil foaming.
I think the cause of the oil foaming was excessive amounts of oil being piled up at the rear end of the case....instead of being distributed elsewhere in the engine (mainly rocker boxes) like a type 1 or a bus based type 4 engine which does not have the rocker box PCV inlets.
I also think that what is not helping it....are the large windows in your windage tray. I get the functionality of them....but...understand that on a fairly steep incline...the two windows that are most rearward in the windage tray are going to let what oil is under the tray....flow right through the windows so its now on top of the tray piled up back against the rear of the case.
Because you still have the PCV line from the oil breather chimney plumbed to manifold vacuum....there is virtually no way that you have gas pressure in the case.
I do not believe that "gas pressure" was the cause of the oil leak. I am betting its the crank seal itself being fully submerged on its backside in a pool of oil...and getting a wave pushed at it every time the crank rotates past it.
You have to bear in mind that for the most part the fan seal will rarely have oil fill all the way up to the seal.
So you got no oil pressure loss this time with the rocker box vents plugged off. That is progress.
A couple of things you might try for an experiment.
1. So in general ...ACVW's tend to get the left rocker box full of oil. The type 4 with no rocker box vents should be no different. I think its the D-jet style pull through ventilation that is putting this oil back in the case where it would not normally be on a type 1 or bus engine....and thats too much oil pooled in the back on and incline.....so.....leave that oil in left head.
Block off the left rocker box vent....and just let the right oen flow and see how that works.
2. Try this: So...most people look at the D-jet type 4 PCV system and "ASSUME" that the hoses to the heads allow gasses to vent OUT of the rocker boxes...when in facts it dead opposite.
So....lets try it the other way. Not sure how to do this without adding a fitting or screwing something up......but I am thinking you might want to try taking the hose from the splitter/flame trap...still plumbed to both rocker boxes......and somehow plumb it into the square area under the oil chimney (which is an oil baffle).
So if you have a spare oil baffle chimney. you could add a barb to it like this. (This is a non-PVC style oil baffle)...and dump vapors from the rocker boxes to the underside of the oil baffle to sperate any oil before they go to the manifold.
Ray |
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Keith Park
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Posts: 225
Location: Clifton Park NY
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| Posted: Mon Jul 05, 2021 7:50 pm Post subject: Re: Interesting oil pressure issue |
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Thanks Ray for the in depth writeup, I do have an extra breather box and can try those ideas. Im starting to get a handle on what is going on but...
I just drove it home, 100mi, no boat and ran fine but it still leaking oil out the back, not gushing out but dripping into the fan, It acts like I wiped out the rear main seal, but if the case was not pressurized, Im still not seeing how oil got past it and now that the breathers are back to the way they were its still leaking, unless its something else back there that is dripping oil into the fan...
Stumped... Just hope I can change that seal with the engine in the car as I wont have time to pull it till at least next year. |
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raygreenwood
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Location: Oklahoma City
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| Posted: Mon Jul 05, 2021 9:41 pm Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
Thanks Ray for the in depth writeup, I do have an extra breather box and can try those ideas. Im starting to get a handle on what is going on but...
I just drove it home, 100mi, no boat and ran fine but it still leaking oil out the back, not gushing out but dripping into the fan, It acts like I wiped out the rear main seal, but if the case was not pressurized, Im still not seeing how oil got past it and now that the breathers are back to the way they were its still leaking, unless its something else back there that is dripping oil into the fan...
Stumped... Just hope I can change that seal with the engine in the car as I wont have time to pull it till at least next year. |
A couple of things can wipe out that seal. Just for the heck of it check that your fan bolts are not too long. They can trash the seal. Also check to make sure its actually that seal.
Also...sometimes seals once they start leaking from whatever cause...never fully seal if they get distorted.
The last iteration I saw of Jakes windage tray mods had extra slots near the cam. I never saw one with full windows but I may be behind.
BUt....it is a vague possibility that with the head inlets plugged......and the 2.5 to 3mm restrictor in place above...that you are either pulling vacuum on the case or there is not enough flow and you are getting pressure.
Ray |
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Keith Park
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Location: Clifton Park NY
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| Posted: Tue Jul 06, 2021 6:22 pm Post subject: Re: Interesting oil pressure issue |
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Well the plot thickens.
I had some time with the car tonight and to look and see where the oil was and where it wasnt. in a T3, there is no rear seal so any crankcase pressure from blowby or PCV issues comes right out the rear of the crank and hits the fan, but in looking carefully at the T4, if that rear seal were leaking Id think it would be running down the back side of the engine first, not into the fan... and the back side of the engine below it was bone dry.
SO... I looked in the cooling air intake plenum, behind the apron in the T3, and it was covered with oil. the ONLY way to get oil in there is thru the dipstick tube... there is a flexable rubber bellows that grommets onto the rear engine bay in back, then over the dipstick tube (a custom modified for this installation but the same idea). but the dipstick holder bezel, bolts onto the inside edge above the rear apron and has a metal tube that pushed down into that rubber bellows that goes thru the plenum with a grommet, but NO clamp, it just slides in. I hope I described this well enough but the oil was coming up around that tube into the dipstick rubber as there is no clamp and getting sucked into the intake plenum by the fan, then into the fan
I lost about half a quart, maybe a wee bit more in 200 miles, 100 of which had the boat behind it and the head vents plugged and was throttle heavy, with a couple miles up that big hill in 3rd at 3900 RPM. Not sure why I was still seeing dripping when I got back and drove it today but maybe its residual, or it is still passing a bit up the dipstick tube but apparently the crankcase, at least with the rocker box vents plugged, is getting pressurized... or at least thats what it seems...
am I making sense?
I put a clamp on that tube, so if it does try to vent again it will do it somewhere else where it wont hit the fan!
as for the windage tray, those mod's date back probably to 2003 or so when I first built the engine, it was a mod pointed to on the forum or somewhere... I tried to copy that. When I ran the first build, without those mods, and no tuna can, it starved horribly on big sweeping highway turns, put the oil light on. No issues with that since.
Thanks |
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raygreenwood
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| Posted: Tue Jul 06, 2021 9:01 pm Post subject: Re: Interesting oil pressure issue |
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| Keith Park wrote: |
Well the plot thickens.
I had some time with the car tonight and to look and see where the oil was and where it wasnt. in a T3, there is no rear seal so any crankcase pressure from blowby or PCV issues comes right out the rear of the crank and hits the fan, but in looking carefully at the T4, if that rear seal were leaking Id think it would be running down the back side of the engine first, not into the fan... and the back side of the engine below it was bone dry.
SO... I looked in the cooling air intake plenum, behind the apron in the T3, and it was covered with oil. the ONLY way to get oil in there is thru the dipstick tube... there is a flexable rubber bellows that grommets onto the rear engine bay in back, then over the dipstick tube (a custom modified for this installation but the same idea). but the dipstick holder bezel, bolts onto the inside edge above the rear apron and has a metal tube that pushed down into that rubber bellows that goes thru the plenum with a grommet, but NO clamp, it just slides in. I hope I described this well enough but the oil was coming up around that tube into the dipstick rubber as there is no clamp and getting sucked into the intake plenum by the fan, then into the fan
I lost about half a quart, maybe a wee bit more in 200 miles, 100 of which had the boat behind it and the head vents plugged and was throttle heavy, with a couple miles up that big hill in 3rd at 3900 RPM. Not sure why I was still seeing dripping when I got back and drove it today but maybe its residual, or it is still passing a bit up the dipstick tube but apparently the crankcase, at least with the rocker box vents plugged, is getting pressurized... or at least thats what it seems...
am I making sense?
I put a clamp on that tube, so if it does try to vent again it will do it somewhere else where it wont hit the fan!
as for the windage tray, those mod's date back probably to 2003 or so when I first built the engine, it was a mod pointed to on the forum or somewhere... I tried to copy that. When I ran the first build, without those mods, and no tuna can, it starved horribly on big sweeping highway turns, put the oil light on. No issues with that since.
Thanks |
Ah...forgot you had a wagon....er...type 3
I forgot you had that dipstick assembly with a boot somewhere in the middle...yep....type 4 cars...wagon version have that too. You may have just blown a boot loose or its just the top gasket where it meets the body.
I still think you have too much oil pooling. Yep....understand why the windage tray mods....but that does not always mean they work in every situation.
Ray |
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Keith Park
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Location: Clifton Park NY
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| Posted: Wed Jul 07, 2021 7:21 pm Post subject: Re: Interesting oil pressure issue |
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yes, my 2056 lives in a different neighborhood now
I think my reasoning with the windage tray was, even larger holes are a whole lot better than not having a tray at all like the busses and T4's. Im pretty sure there was decent pressure in the case pushing the oil out the dipstick tube, as the stock dipstick tube right out of the case also had some spatter around the top as well.
So, trip up saturday, cool day, no towing, shall I try that 1.5mm orifice again or block off the left rocker box hose?
THanks
Keith |
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