Oil issues: Dry Sump, Accusump for road racing?

[Sgt.Gator]

Bob can you find a way to datalog oil pressures? A gauge won't be nearly as good. Temp yes because it doesn't swing like crazy, but pressures fly around fast.

[Bob_n_Cincy]

Bob can you find a way to datalog oil pressures? A gauge won't be nearly as good. Temp yes because it doesn't swing like crazy, but pressures fly around fast.

Yes, I going to bring temp and pressure into my TGV sensor inputs. Hopefully I can get it working by this weekend. The replacement motor is still sitting on the floor. I decided to take Thursday and Friday off work to make sure we make it to the track.
Bob

[STiPWRD]

Yes, I going to bring temp and pressure into my TGV sensor inputs. Hopefully I can get it working by this weekend. The replacement motor is still sitting on the floor. I decided to take Thursday and Friday off work to make sure we make it to the track.
Bob

Bob, what's your approach to logging oil temp? I rigged up the oil pressure sensor you posted a while back but am still trying to figure out what to do about the oil temp. I have the prosport gauge and sensor, which as far as I can tell is a 2.5kOhm thermistor. I'm thinking of connecting this thermistor directly to the gas tank temp sensor wire and recalibrating the temp curve in rom raider logger. Is your plan to do thermocouple to 0-5V conversion board?

[Bob_n_Cincy]

Bob, what's your approach to logging oil temp? I rigged up the oil pressure sensor you posted a while back but am still trying to figure out what to do about the oil temp. I have the prosport gauge and sensor, which as far as I can tell is a 2.5kOhm thermistor. I'm thinking of connecting this thermistor directly to the gas tank temp sensor wire and recalibrating the temp curve in rom raider logger. Is your plan to do thermocouple to 0-5V conversion board?

I'll let you know tomorrow. I'm going to try a thermistor type sensor with a voltage divider resistor. connect it to the TGV sensor plug. The trick will be playing with the table to make it read out in degrees F.
Bob

[STiPWRD]

I'll let you know tomorrow. I'm going to try a thermistor type sensor with a voltage divider resistor. connect it to the TGV sensor plug. The trick will be playing with the table to make it read out in degrees F.
Bob

Bob, can you check my math?

Vo = (R*Vcc)/(R+R_ref)

where: Vo is the output voltage, Vcc is 5V, R is the thermistor value, and R_ref is the fixed resistor value for tuning the curve. For a 2.5kOhm thermistor and a 1kOhm fixed resistor, I'm getting this type of response curve:
thermistor circuit.jpg

For R_ref = 400 ohms, I get:
400 ohms.jpg

[RetroRacing]

We are using an IQ3, oil pressure is 90psi when warm, waiting for oil temp to log but with the 20 row cooler, pretty sure we will be ok. Love a digital dash........

[Bob_n_Cincy]

Bob, can you check my math?

Vo = (R*Vcc)/(R+R_ref)

where: Vo is the output voltage, Vcc is 5V, R is the thermistor value, and R_ref is the fixed resistor value for tuning the curve. For a 2.5kOhm thermistor and a 1kOhm fixed resistor, I'm getting this type of response curve:
thermistor circuit.jpg

For R_ref = 400 ohms, I get:
400 ohms.jpg

Your graphs looks correct.
Is there a table in the ECU for the TGV so the SSM will spit out temperature in degrees C or F?

[STiPWRD]

Your graphs looks correct.
Is there a table in the ECU for the TGV so the SSM will spit out temperature in degrees C or F?

I've looked at the definitions file for rom raider logger and the ecu raw value for TGV data is V*50. So the logger must divide this raw value by 50 to show the true TGV voltage. I don't know if this expression can be changed directly in the ecu but it can be changed in the logger by modifying the definitions file (.xml). You'd need to know the function of temperature vs voltage for whatever sensor you're using.

For instance, the raw value expression for the fuel temp sensor is:
For degrees F ==> "32+9*(x-40)/5"
For degrees C ==> "x-40"
where x is the ecu raw value.

One thing I'm going to try is connecting the thermistor that came with my prosport oil temp gauge to the gas temp signal wire and record the raw ecu value when dipping that thermistor in a cup of water at different temperatures. This should give me a calibration curve that I can update in the logger definition file. I'm not sure how linear that curve will be as thermistors tend to follow:
1/T = 1/To + (1/B)*ln(R/Ro)

[Sgt.Gator]

Is anyone here aware of an 818 with a mandrel pulley coming off the crank pulley and fitting in an 818? I'm sure it's a very close fitment, trying to figure out if it will clear the frame and firewall.
A couple of shots of a DS pump using the mandrel:
new_avi_180.jpgcosworth-ej20-dry-sump.jpg

The more I look at them the more I think they won't fit!

[Mulry]

This is what we are going to do. We have test fitted the engine in the chassis and it appears that the crank mandrel will miss the structure of the frame/firewall. We are working on custom fabrication of the DS pump mount so that we know our center-center distance before ordering the mandrel for the crank and the pulleys for the pump and the crank mandrel.

The real trick in your first photo is that the line routing out of the bottom of the DS pump would wrap around the outside of the exhaust headers, which might do very bad things to those oil lines. We've mocked up the routing around the rear of the engine to avoid that situation, but no final conclusions yet.

[Sgt.Gator]

This is what we are going to do. We have test fitted the engine in the chassis and it appears that the crank mandrel will miss the structure of the frame/firewall. We are working on custom fabrication of the DS pump mount so that we know our center-center distance before ordering the mandrel for the crank and the pulleys for the pump and the crank mandrel.

The real trick in your first photo is that the line routing out of the bottom of the DS pump would wrap around the outside of the exhaust headers, which might do very bad things to those oil lines. We've mocked up the routing around the rear of the engine to avoid that situation, but no final conclusions yet.

Thanks, I'm looking forward to seeing your fitment pic.
I routed the lines as you see in the pic on my LGT, it was no problem. Obviously not as tight as the pic, and I put firesleeve on them. It's pretty easy to find a way to pull them a few inches away from the headers. To go straight back over the back might be possible in a 818, much harder in a LGT or STI.

[RetroRacing]

Gentlemen, the jury is in, you must have a dry sump if you are pulling these kind of g's.

[Scargo]

Gentlemen, the jury is in, you must have a dry sump if you are pulling these kind of g's.

And what would that G limit be? What have the R's been capable of? A deep KB pan and Accusump setup has failed (when there were no oil heat issues)? I know a lot of questions but I've been out of touch and can't keep up with failures and DS/non-DS successes.

[Mulry]

It wouldn't surprise me if Retro had some logged data to answer this precisely (and Plavan probably does too), but I suspect that you would hit this limit even on 200 treadwear tires. It seems like there are a lot more DS failures than non-DS successes. There's a reason that every competition boxer engine gets dry sumped, and it's not because teams like spending extra money and complexity on dry sump systems.

[C.Plavan]

IIRC I was pulling 1.5G+

I would not even track a 818S on street tires without a drysump.

Dry Sump failures on 818R's- There only one I can think of (Brando). However, he did not have any oil temp, oil pressure, or any other gauges. He also did not have an external oil cooler.

I remember he blew up a motor without the drysump after 1.5 track days, then had the motor rebuilt and the engine builder REUSED the factory oil/water heat exchanger with all those metal bits inside. Then quickly blew up that motor.....and the tune was suspect and possible turbo hose failure (Boost controller)

Save your money and ADD a drysump..... It's not going to hurt as much as blowing motors. If you think a deep pan, an AOS or Killer B valve is going to save you, Just start throwing money away or paypal me. I'll put the money to better use!

My car has over 20 track days now including the new owner. Still working great (knock on wood). Also, do not use the 11mm oil pump- the 10mm oil pump fixed my oil heating issues. It bypassed the whole time just circulating the oil inside the motor. See oil pump flow chart...

[Sgt.Gator]

Chad I think the only note to make about the oil pumps is to use the 10mm for a stock-oem block, especially on a SAVCS oem motor. A forged built block may need an 11 or 12 mm. On my new forged block from Rallispec they said the min pump is the 11 mm and the 12mm is preferred. I went full monty with the Cosworth 12mm pump. So if your builder specs an 11 or 12 I think you should follow their guidance.

[C.Plavan]

Chad I think the only note to make about the oil pumps is to use the 10mm for a stock-oem block, especially on a SAVCS oem motor. A forged built block may need an 11 or 12 mm. On my new forged block from Rallispec they said the min pump is the 11 mm and the 12mm is preferred. I went full monty with the Cosworth 12mm pump. So if your builder specs an 11 or 12 I think you should follow their guidance.

Mine was a non-OEM built motor. SAVCS yes

[RetroRacing]

We were running slicks, 235 front, 265 rear. Our logger was not working, but we know what the issue was. Blow by was stupid, even with the Grimmspeed AOS, killer b pan and pickup, we went down a quart and Pooched the engine after maybe 40min of track time.

Oil temps are not an issue with the 11mm pump from Rally sport, 95psi pretty much all of the time as far as I could see, with oil temps under 190 with the external cooler. Its all about the oil control, which the dry sump seems to take care of.

[Zach34]

We were running slicks, 235 front, 265 rear. Our logger was not working, but we know what the issue was. Blow by was stupid, even with the Grimmspeed AOS, killer b pan and pickup, we went down a quart and Pooched the engine after maybe 40min of track time.

Oil temps are not an issue with the 11mm pump from Rally sport, 95psi pretty much all of the time as far as I could see, with oil temps under 190 with the external cooler. Its all about the oil control, which the dry sump seems to take care of.

So, for those of us who are a little slower to the barn - why did you have so much blow-by and how did that cause the engine to fail?

[RetroRacing]

It blew out a quart of oil, which I guess is enough to starve the pickup in even a Killer Bee pan.

[Scargo]

Blowby is usually a ring issue. Extreme boost will cause more blowby and the oil sloshing and crank/rod whipping possible when racing exacerbates the oil mist. Hoses too small going to the AOS will increase air velocity and move more oil mist out of the crankcase.
I have never been a fan of capturing and holding the oil; especially in a track car. I feel it should be allowed to return to the crankcase. This, after I blew a stockish, 2008 STi motor. I was at the track and the AOS filled and overflowed back into the intake, causing detonation and broken pistons. After replumbing, I've run the same 500 HP motor for three years on the track with the AOS dumping oil back into the engine through the PCV hole. Granted, my STi cannot generate the G's a well-prepared 818R can but it was doing competitive ST2 laps.

[Scargo]

It blew out a quart of oil, which I guess is enough to starve the pickup in even a Killer Bee pan.

Per my comment, where did the quart of oil go? Did it overflow the tank and where does the vent go? I cannot imaging a quart causing starvation but perhaps on a long sweeping turn it could (without an Accusump). I believe it is common practice to slightly overfill when racing a Subie.

[RetroRacing]

We did overfill a bit, we were running the Grimmspeed oil cap style AOS that dumps it back into the pan, but the amount of oil going into the intake was too much, so we changed it to a dump can, for one session. We are running 1lb Under stock boost.

[JeromeS13]

We did overfill a bit, we were running the Grimmspeed oil cap style AOS that dumps it back into the pan, but the amount of oil going into the intake was too much, so we changed it to a dump can, for one session. We are running 1lb Under stock boost.

I've never heard of anyone with success using the Grimmspeed AOS on the track.

[Sgt.Gator]

I've never heard of anyone with success using the Grimmspeed AOS on the track.

+1 on that.

[killerbmotorsport]

It blew out a quart of oil, which I guess is enough to starve the pickup in even a Killer Bee pan.

Oil level in the pan drops when the engine is running. Compound that with corner loads and the outside facing head starts to hold oil as well. This can very simply be simulated on an engine stand by tipping the engine. You can see oil begin to pool into the lower (outside facing) head, and the sump level drop. Remove an additional quart and that level gets dangerously low. At those forces the balance and vent lines are also going to be holding oil as well, further reducing the level in the sump.

The OEM STi get flakey ~1.2Gs and the older flat bottom pans are even worse. The 818 easily produces forces well above that.

I'd still like to see datalogs regarding our setup (pan/pickup/baffle and oil control valve) with a properly setup A/O separator showing starvation.

Agree with Scargo, A/O separator is the way to go on these engines vs storing oil in a can.

[mikeb75]

+1 on that.

+2, bad things happened.

[Mitch Wright]

Had a DS ordered a while back, made a U turn and continued to research running a wet sump. I guess I have just dug my heals in and am determined to run my wet sump successfully. Read all I can find and talked to all that would e-mail or pick up the phone from North America, Europe and Japan. I am logging, pressures, temps and g loads so I will find out soon.
I will take all the I told you so's if I am not successful but I am going forward with confidence.

[Scargo]

I feel the key to my 490 CHP/395 WHP engine longevity, in my ST2 level STi... is all the Killer B parts, the Accusump, the large oil cooler, large, external oil filter and simple A/OS that drains back. Almost nine quarts of oil. According to others, the two quart Accusump can do a few seconds of supplemental oil supply. It seems like mine takes a bit longer to bleed down. It should come into play as a transition to it as the pressure drops rather than a sudden dump. I have not been on a track that exceeds 11 seconds of sustained G's. It survived that track (NJMP Lightning) many times. Lightning is not very banked, but it has also survived multiple days at NHMP, Watkins Glen, Palmer and Thompson (all in the N-E). I don't have data-logging but I'm sure other ST2 cars have data that can be found. John George comes to mind.
Please don't get the idea that I am saying positively that you can get by without a DS on a high G 818R. DS's the route I plan to take.

[FFRSpec72]

Granted my car was not running to it's fullest but I did feel the potential of the car in the corners. I currently have a wet sump much like Mitch (with Killer-B and Cosworth components). I have ordered a Elements Tuning DS after feeling the car and also what happened to retroracing. I really did not want to have to do this and mainly doing this as insurance. My plan is to keep the oil cooler setup, run the stock oil pump and pulley system and just add the DS. I have a AOS and Killer-B Oil Control Valve and not sure what I will do there. The center drive 818 is running the element tuning DS but also is running a AOS due to oil in the throttle body.

[RetroRacing]

I'm not saying that you could make it work with the full KB setup and accusump for an hour, or maybe even two, but I have doubts about 25 hours of 2g corners. Our system was supposed to empty into the oil fill, but the shear volume of oil was to much for it to handle.
Our second engine is back into the car awaiting the dry sump for the end of this week. We had to also do some serious thermal control under the hood, we melted the timing belt cover even though we have the full exhaust wrapped.....

[Wayne Presley]

. We had to also do some serious thermal control under the hood, we melted the timing belt cover even though we have the full exhaust wrapped.....

The Lotus Elise/Exige has NACA ducts in the belly pan to bring cooler air into the engine compartment

[RetroRacing]

We thought about that, but you lose downforce as a result. We are venting the top for now

[Sgt.Gator]

We had to also do some serious thermal control under the hood, we melted the timing belt cover even though we have the full exhaust wrapped.....

Holy Heat Soak Retro!

At least at Thunderhill it should be less than 103 degrees in December....if not snowing.

[Zach34]

we melted the timing belt cover even though we have the full exhaust wrapped.....

Good heavens..... How the hell do the Porsche turbo motors not melt everything?

[Sgt.Gator]

The center drive 818 is running the element tuning DS but also is running a AOS due to oil in the throttle body.

This makes no sense to me. Every DS system I've seen in a race car eliminates any possibility of oil in the intake because the PCV, hoses, breathers, all that stuff, are gone. In a street car like a Corvette Z06 that comes with a factory dry sump oil in the intake occurs because all that stuff is still hooked up. But in a race car it should be gone.

For my new STI engine I'm considering making a custom hard pipe intake simply because there is no reason to have all the vacuum spigots on a stock or aftermarket intake pipe. Since I'll be running a VTA BPV there is no need for any openings in the intake pipe at all. That eliminates several potential points of failure if there are no caps, plugs, or hoses that can pop off.

I hope to see the centerdrive 818 soon at an event so I can understand why they still have an AOS and oil in the intake tract.

[Scargo]

What Sgt Gator said... I tried to post this earlier from my phone. In a racing application, why would you ever want to pull a vacuum on an A/OS from the intake manifold, when you can vent to atmosphere? Perhaps you could avoid breakage with forged pistons and low boost but performance would suffer if significant oil gets pulled in.

[STiPWRD]

For my new STI engine I'm considering making a custom hard pipe intake simply because there is no reason to have all the vacuum spigots on a stock or aftermarket intake pipe. Since I'll be running a VTA BPV there is no need for any openings in the intake pipe at all. That eliminates several potential points of failure if there are no caps, plugs, or hoses that can pop off.

Doesn't the boost control solenoid need a vacuum reference pre turbo?

[RetroRacing]

The issue, as explained to me by Elements, is that some guys don't just vent the valve covers to the DS tank. Pulling vacuum top and bottom of engine negates the benefit of both. Shouldn't the EGR be closed off and the valve covers be just vented directly to the DS tank to retain vacuum in the block?

[FFRSpec72]

This makes no sense to me. Every DS system I've seen in a race car eliminates any possibility of oil in the intake because the PCV, hoses, breathers, all that stuff, are gone. In a street car like a Corvette Z06 that comes with a factory dry sump oil in the intake occurs because all that stuff is still hooked up. But in a race car it should be gone.

For my new STI engine I'm considering making a custom hard pipe intake simply because there is no reason to have all the vacuum spigots on a stock or aftermarket intake pipe. Since I'll be running a VTA BPV there is no need for any openings in the intake pipe at all. That eliminates several potential points of failure if there are no caps, plugs, or hoses that can pop off.

I hope to see the centerdrive 818 soon at an event so I can understand why they still have an AOS and oil in the intake tract.

My understanding is that the remote oil cooler and filter can be left as it is, the AOS and Killer-B Oil Control Valve can be left as it as these attach to the valve cover vents and the Dry Sump is a stand alone system, so basically you have 3 stand alone systems (1) Oil Cooler/remote Oil Filter (2) Valve cover venting system (AOS and Oil Control Valve) aand (3) Dry sump, pan, pump and tank