More discussion re. oiling

#1

Paul Poore the exhaust guy gave me a call this morning. It was a very interesting conversation. Here’s some of the highlights.

  1. I thought that he was just some muffler guy. Turns out that he builds and support SpecE30’s. He’s done a lot of tinkering and experimenting on various aspects of our cars and engines so he has a lot of insight into what works poorly and how one might make it work better. If I lived anywhere near him I’d be buying him beer and hanging out in his shop a couple evenings a month just to learn.

  2. He has AIM data from one of his supported SpecE30 types that shows oil pressure dropping to 8psi once/lap at Summit. I’ve not been there, so I don’t know how Summit’s turns compare to tracks in the SE. I’ll leave it up to that driver to identify himself if he wishes.

  3. Based on the cars Paul’s been supporting over the years, he seems pretty convinced that there is a systemic oiling problem in the M20B25 associated with the pickup sucking air. I think that he would point to the #6 rod bearing as the most vulnerable bearing.

  4. Measuring oil pressure can be tricky. We don’t know the response time of different sensor/gauge combos but he percieved VDO as responding faster then Autometer. The location of the oil pressure sensor is important too. The stock oil pressure sensor location is good for measuring transient pressure losses at the pump, but less good for measuring transient pressure losses at the galley. An Accusump, checkvalve, and/or large aftermarket oil cooler add additional variables.

Because I have a checkvalve in my new oiling system, I should be able to get oil pressure data at the pump that is unnaffected by the Accusump. After this conversation with Paul, I’m going to put the project of connecting oil pressure data to the Traqmate on the front burner.

  1. He perceives Chuck’s I-J Crankscraper as the better of the couple types he’s worked with. Better meaning it doesn’t require as much modification to fit. Further, because of the high location of our crank above the crankscraper, he sees the scrapers available to us as baffles first, and scrapers 2nd. He does not perceive the scraper as a slam-dunk solution. It should reduce the incidence of sucking air, but it won’t eliminate it. The scraper, for example, didn’t change the oil pressure losses at Summit.

  2. He leans toward the school of thicker oil. I don’t think that he would tell you straight out that “you should run xW50”, but I’d see him recommending 40 or 50 and probably not 30. Showing my innate fair-minded reasonableness, I bought a bunch of 20W50 last night.

Posted with permission. Hopefully I accurately represented his views.

#2

I had that same conversation with him a month or so ago when I ordered my exhaust. He is the one that swayed me back to using Valvoline VR-1 racing oil. He does seem to be very knowledgeable.

John

#3

Ranger, the stock oil pressure sending location is a “T” off the main gallery. That is where pressure should be taken. CB

#4

cwbaader wrote:

Ahh. That’s good to know, thx. I thought that the oil pressure sensor was between oil pump and oil filter. That means I’m going to be defeated in my attempt to monitor the oil pump sucking air because the Accusump will drive the oil pressure there. Shit, I really wanted data that would indicate what was going on after the pump.

After struggling all evening to get my motor mated to my transmission, and failing, I’m too tired and pissed off to rethink the oiling system design. There’s been so many late nights with all of this that I’ve not seen 6hrs sleep in weeks. I think that I’ll just have a beer and go to bed.

#5

All that matters is whether the oil gallery looses pressure. If there’s no loss of pressure in the gallery oil is flowing to the bearings.

#6

jlevie wrote:

I understand, but if the Accusump keeps the pressure up in the galley and that’s also where I’m measuring pressure, then I won’t know when the oil pump sucked air. Maybe I don’t really don’t have to know, but I want to know.

Consider how significant it would be to know for a dead certainty that every lap your oil pump sucked air and only your Accusump kept up oil flow to the galley.

Right now my I have 2 oil pressure switches (for amber and red), and one oil pressure sensor. They are all in a common “manifold” so they’re sensing pressure at the same place. It would be easy tho to move the amber switch to somewhere on the other side of the Accusump checkvalve.

A solution is to get an oil filter sandwich adapter that has 1/8NPT ports in it. With multiple ports you could even tie in a second oil pressure sensor to run a secondary gauge. But that would be overkill when you can’t even get your motor back into your car.

#7

Ranger wrote:

[quote]jlevie wrote:

I understand, but if the Accusump keeps the pressure up in the galley and that’s also where I’m measuring pressure, then I won’t know when the oil pump sucked air.[/quote]

Is there a way to measure flow in to/out of the Accusump? That would tell you when galley pressure drops/

Steve D.

#8

Steve D wrote:

[quote]Ranger wrote:

[quote]jlevie wrote:

I understand, but if the Accusump keeps the pressure up in the galley and that’s also where I’m measuring pressure, then I won’t know when the oil pump sucked air.[/quote]

Is there a way to measure flow in to/out of the Accusump? That would tell you when galley pressure drops/

Steve D.[/quote]

I can measure air pressure behind the Accusump piston, so that’s a thought. That would require a fudge factor tho because you’re supposed to have 7-10psi of air in there to make sure that the Accusump never entirely fills.

I did some research on flow meters, but they are all too expensive.

I am surprised that no one has commented on the report of the oil pressure dropping once/lap at Summit, even with a crankscraper. That struck me as pretty significant.

#9

Ranger wrote:

[quote]
I am surprised that no one has commented on the report of the oil pressure dropping once/lap at Summit, even with a crankscraper. That struck me as pretty significant.[/quote]It would be more significant if a correlation was shown between racing at Summit and blowing up your motor. I’m not aware of that being a pattern. Anyone in MA care to comment?

#10

I think I’m gonna set my car up for data logging OP at 2 points.

One is at the stock OP sending unit location. If I remember correctly that’s the sender at the bottom of the block halfway back on the exhaust side. Any reason why I can’t install a short pipe nipple and a tee to retain the stock sending unit?

The second will be at a sandwich plate between the block and filter/t-stat adapter. Besides pressure, I can also connect an oil temp gauge there, though I don’t intend on logging oil temps.

That will let me observe how much “accumulator” effect the oil cooler and oil galley circuit provides to the oil pressure at the bearings. This will be great in identifying how low your oil pressure really goes and whether an Accusump is really justifiable or not.

#11

rrroadster wrote:

[quote]I think I’m gonna set my car up for data logging OP at 2 points.

One is at the stock OP sending unit location. If I remember correctly that’s the sender at the bottom of the block halfway back on the exhaust side. Any reason why I can’t install a short pipe nipple and a tee to retain the stock sending unit?

The second will be at a sandwich plate between the block and filter/t-stat adapter. Besides pressure, I can also connect an oil temp gauge there, though I don’t intend on logging oil temps.

That will let me observe how much “accumulator” effect the oil cooler and oil galley circuit provides to the oil pressure at the bearings. This will be great in identifying how low your oil pressure really goes and whether an Accusump is really justifiable or not.[/quote]

See my oiling project document at www.gress.org.

The thread at the OEM OP switch port is 12X1.5. If you have the OEM OP switch, throw it away. Get a 12X1.5 to 1/8NPT adapter, and then you can put anything in there that you want. OP sensors and switches are all 1/8NPT. It’s the temp sensors and switches that are bigger. I have a spare 12X1.5 to 1/8NPT adapter that I’m probabably not going to use. 2 beers and it’s yours.

The OEM OP switch port is off of the galley, something I just learned last week. If you have an Accusump and/or checkvalve, having gauges and warning light indicate what is happening at the galley and at the oil pump gets a little more complicated.

Ultimately, I’ll probably do what you’ve described and put an OP switch on an oil filter sandwich. My Accusump checkvalve is after the oil filter and will therefore isolate pump OP from galley OP. Or so my scheme goes. The sandwich is en route, but won’t get here by RA.

When I get this hooked up to the Traqmate, I’ll just log oil pump data because that info will help everyone. But me personally…Warning lights will tell me what’s going on at the galley.

#12

You need to be careful about where the “sandwich” samples oil pressure. I’m not sure whether the pump output is to the perimeter or to the hollow bolt. One of those is direct to the oil gallery where the OE sensor is. I’d guess that the output of the pump goes to the outside of the filter, which would mean that to see the pump output your sandwich needs to look at that.

#13

Yup, I think Paul is one of the resources like Patton had in mind, he is a wealth of knowledge. I definately agree with the thicker oil…I also ran an accusump on am M30 engine, it was great peace of mind. The spot where pressure drops at VIR is oaktree, when I saw the light flash there, it was time to replace the motor, once I installed a junkyard motor with accusump I never had another problem, this was an M30 though…

\Anyone see their oil light flash at Oak Tree turn?

Al

#14

More oil sensor stuff.

Oil temp sensing is kinda a pita. Getting sensors right in the oil flow is harder then getting oil pressure. Currently I have an oil temp sensor and a 230deg oil temp switch (for amber light). Both of those are located to get hot oil temps, but I want to get cool oil temps too. So I thought that I would put a sensor in after the oil cooler, and then put a switch on my oil temp gauge such that it can switch between indicating hot oil temp and cold oil temp.

Oil pressure at the galley, pump and Accusump. I’m currently set up for oil pressure at the galley (via the OEM port), but I want to see oil pressure at the pump, and air pressure in the Accusump too. The oil pressure at the pump sensor could also feed data to the Traqmate, and a warning light there would provide interesting realtime feedback that you just sucked air in that corner.

The Accusump uses a 7-10psi(?) charge of air behind it’s piston to ensure that it is always a little higher pressure then the oiling system. In order to pressurize the oil galley you open the Accusump valve briefly, and then close it, before starting the car. Then you start the car and slowly open the valve back up. This allows you to fill the Accusump back up without diverting too much oil from your motor all the sudden. If you can see the air pressure gauge on the Accusump, you can see all this happen.

One thing that I noticed is that if the motor is off, oil flows thru the bearings very slowly. If your engine dies suddenly, say by shredding teeth off of a t belt, the Accusump holds it’s pressure for minutes, not seconds. Interesting.

I’m not sure if I mentioned it in another thread, but I would have expected 225eg coolant temp at RA last weekend, but thanks probably to my big-ass TruCool oil cooler, my coolant temp was only 180deg. Sadly I didn’t get oil temps. In the last minute scramble I didn’t get that working.

#15

Ranger wrote:

[quote]Paul Poore the exhaust guy gave me a call this morning. It was a very interesting conversation. Here’s some of the highlights.

    1. He leans toward the school of thicker oil. I don’t think that he would tell you straight out that “you should run xW50”, but I’d see him recommending 40 or 50 and probably not 30. Showing my innate fair-minded reasonableness, I bought a bunch of 20W50 last night.

Posted with permission. Hopefully I accurately represented his views.[/quote]

One more thought about the “thicker is better” concept. This is an area I have studied quite a bit over the years and where I believe that thicker “synthetic” oil adds a little safety margin over 20W50 mineral oil. I realize that this is a highly debatable point but the facts are that none of us really knows exactly what happens at the precious moments during an oil starvation related bearing failure. In fact it can be argued that such detail varies from incident ot incident. That being the case, the ability of synthetic oil to maintain film strength at elevated temperatures better than dino oil is worth the $25-$50 extra cost per oil change imho.

The difference between brands, formulas, ZDDP quantities, etc. is an entirely different subject to which there are volumes upon volumes of arguments posted all over the web. My point is any just about any xW50 synthetic oil is better than dino oil when it comes to reducing the risk of engine failure regardless of all other precautions.

Don

#16

Ranger wrote:

[quote]
I am surprised that no one has commented on the report of the oil pressure dropping once/lap at Summit, even with a crankscraper. That struck me as pretty significant.[/quote]

Was it a complete drop in pressure (instant) or a gradual dip then recover? A complete drop could indicate a momentary loss in communication from the sensor (bad/loose wiring, sensor delay, etc.). If the pressure dips then comes back up, you probably do have a loss in pressure.

#17

OriginalSterm wrote:

[quote]Ranger wrote:

[quote]
I am surprised that no one has commented on the report of the oil pressure dropping once/lap at Summit, even with a crankscraper. That struck me as pretty significant.[/quote]

Was it a complete drop in pressure (instant) or a gradual dip then recover? A complete drop could indicate a momentary loss in communication from the sensor (bad/loose wiring, sensor delay, etc.). If the pressure dips then comes back up, you probably do have a loss in pressure.[/quote]

The data unambiguously indicated that the oil pump was not producing pressure in left turns. Later I got the info first hand when I talked to the guy who collected the data. He said that oil pressure was dropping to zero or nearly so in all left turns and many right turns. I say again, all left and many right turns.

We could use more data from other folks, and I’ll do my part to attempt to collect it, but I’m sensing a smoking gun.

#18

I have a green light now to reference my conversation with Jon Allen. He was the one who connected the data logger to his oil pressure switch and found that his oil pickup seemed to be sucking air on all left’s and many rights. He collected data both with and without a crankscraper.

Boys and girls, that’s “all lefts” and “many rights”. “All” and “many”.

Jon and Paul Poore are now doing some testing with Paul’s latest oil pan design.

Personally, I think that the easier way to address this is with an sump, be it Accusump or Moroso’s sump. It’s gotta be hard to create a still oil zone in the crazy sloshing and whirling environment is our oil pan. A sump and some plumbing just isn’t that expensive as long as you use hydraulic, and not aviation grade, fittings.

#19

Scott, or whomever is going to the accusump/accumulator. How about plumbing it directly to the OP pickup on the side of the block? No check valve needed. The hole for the OP unit is the same size as the oil gallery. You can check your OP off the back of the AS/ACC. Chuck

#20

cwbaader wrote:

My plan when thru a lot of variations, and that was one of them. The 12mm OP port in the block should be a workable diameter for the Accusump. But by the time I someone told me that the OP port connected right to the galley, I was already emotionally committed to connecting my OP manifold there.

Anyone know the dia of the connection between the OP port and the galley? For all I know it narrows down considerably.

I still like the idea of the checkvalve tho. It’s a comfort to know that all oil flow from the Accusump would be going to the galley and not to pressurize the oil cooler and oil filter. In the OP port scenario, the checkvalve could go into the line from the oil cooler to the block.