Boig Motorsports

Visit our community sponsor

Thanks Thanks:  2
Likes Likes:  2
Page 19 of 19 FirstFirst ... 9171819
Results 721 to 739 of 739

Thread: Oil issues: Dry Sump, Accusump for road racing?

  1. #721
    Junior Member
    Join Date
    Dec 2017
    Posts
    3
    Post Thanks / Like
    I tend to write epic...

    Though an outsider to both Subaru drivetrains and Factory Five products, I've used baffled oil pans, Accusumps, and a dry sump, so would like to contribute to this discussion. My one-off (Midlana.com) uses a Honda K24 mounted mid-engine and is turbocharged. Honda K-series engine suffer similar oil starvation in turns but in a different way from Subarus. The Honda I4 engine is mounted with the timing chain on the right side of the car and in long left turns, the oil sloshes to the right and covers the front sprocket and timing chain. The timing chain unfortunately acts like a conveyor belt, lifting oil up out of the pan and flinging it into the cylinder head. A very different engine but with similar results due to hard cornering.

    So there's the Accusump. For those who don't know what it is, think of plumbing a rubber balloon into the oil system. When the car starts, oil pressure inflates the balloon until equilibrium is reached. If at any time oil pressure drops, the balloon pushes oil back into the oil system to maintain pressure - that's pretty much it in a nutshell. I had one but got rid of it, and to explain why, well...

    The mechanical shutoff valve should be used for mechanical reasons, better flow, reliability, and lower cost. The problem is that you *will* forget to open it before starting the engine, losing the "pre-oiling" feature. That in itself isn't a fault of the product, it's just something you have to remember before heading out on-track. Likewise, when you come in off-track and shut everything off, if you forget - and you will - to close the valve first, 2-3 qts of oil get pushed back into the system when you kill ignition. That's fairly harmless, but it means when you go to start the car, you again don't get the "pre-oiling" feature, and have 2-3 extra qts of oil flaying around until you open the valve and the Accusump charges. Again, it's not really the product's fault but is, again, something you have to remember to do. There's that, and then there's something someone told me that ate at me until I decided it was a real problem. Disclaimer: This is only a theory of mine which may not be completely true, but I've fully bought into it.

    The theory is that there are problems with using an Accusump and assuming it's fixed the oil supply problem. The problems are all related to how oil in a traditional oil pan takes on the consistency of chocolate milk when the engine's running hard due to air getting whipped into it, sometimes a lot of air. So you head out on-track and really start leaning on the engine. As you probably know, the crank doesn't actually touch the bearings, it's floating on a layer of oil, and that's great, until it isn't. The problem is that when on-track and at high rpm, oil viscosity drops way off and the high rpm "stirs" a tremendous amount of air into the oil, sometimes as much as 50%. This means that the "wedge" of oil keeping the crank away from the bearings is no longer 100% oil, but is maybe as low as 50% oil. This effectively cuts the viscosity in half again because the air compresses easily in comparison with the oil, and means the crank is riding dangerously close to the bearings. Unfortunately, the oil pressure gauge is no help because 60 psi oil pressure reads the same as 60 psi air pressure. Additionally, the Accusump can't help because the air/oil emulsion is at the same pressure as the oil in the reserve tank, so the Accusump doesn't push any oil back into the system.

    Another situation: You're cornering hard when all the above is going on and oil sloshes to one side of the pan, allowing the oil pump to start sucking in larger bubbles. Because they're bubbles, they're followed closely by more oil, so the air gets compressed along with it. In this situation you're right back to the above situation, where you have 60-psi air bubbles in your 60-psi oil, so again, the Accusump doesn't get involved, the oil pressure gauge continues to read normally, but your steady supply of oil to the bearings is now "hiccupping", further worsening the oil situation.

    So during the hard corner, the pump finally sucks in enough air that pressure drops off. If this is the first time it's happened, the Accusump works as designed and pushes fresh oil into the system to prop up pressure. But suppose this is the second, fifth, or tenth time it's happened on-track. When pressure is regained after the corner, the oil pump dutifully recharges the Accusump - with an air/oil froth. Have that happen a few times and now the Accusump now contains a 60-psi oil - and air mixture - ready to be pushed back into the system. Is it better than nothing, yes, but just that.

    Related to the above, air takes a long time to separate out from the oil. In a dry sump tank, the returning oil is fed into the tank tangentially such that it swirls around the wall of the tank, imposing high G-forces on the mixture. The force de-aerates the oil far faster than it does sitting still inside an oil pan or Accusump. In the case of the Accusump there's another potential problem, that if and when that air separates out from the oil, where does it go? It stays in the Accusump, pressurized to 60-psi just like the oil, ready to be fed back into the engine the next time there's a need. If the Accusump is oriented with the outlet upward, that big air bubble is going to be the first thing into the oil system. If the tank is oriented with the outlet downward, the air remains trapped within the tank. This is a problem that gets worse over time because as the air continues to "off-gas", it forms a bigger and bigger bubble at the top of the tank. After a while, the "2-3" quart Accusump actually contains maybe 1.5 quart of oil and 1.5 qts of air.

    In addition to all the above, there's one more thing which may or may not be a problem, which happens coming out of a turn that required the Accusump to "dump its load" into the engine. In that situation, the OEM oil pump is having to supply full oil pressure to not only the engine, but also the partially-empty Accusump reservoir. Does the OEM pump have the capacity to send oil to both at the same time? Who knows.

    I'm afraid that in the case of the oil system, you really do get what you pay for. The harder you plan to run the engine and the more G forces it's going to see, the more a dry sump becomes less optional. As said above, this is a working theory of mine that I've "decided" is true without doing any testing with an Accusump. If someone using an Accusump to fix a known oiling problem finds no bearing issues during a rebuild, well, maybe I've decided too much.
    Last edited by kb58; 01-12-2018 at 08:08 PM.

  2. #722
    818r center seat biknman's Avatar
    Join Date
    Mar 2011
    Location
    Charm City
    Posts
    75
    Post Thanks / Like
    Blog Entries
    2
    FYI

    RCM has a 5 stage drysump kit now : https://rogerclarkmotorsport.co.uk/s...ystem-ej202225

    FF 818r 119057 Instagram biknman69
    July 18 2019 Ascent Touring, 17 Legacy DD, 96 GC coupe 22B build
    “There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely games.”
    • Ernest Hemingway

  3. #723
    Sgt.Gator's Avatar
    Join Date
    Apr 2013
    Location
    Bend, Oregon
    Posts
    1,126
    Post Thanks / Like
    My STI is rebuilt and racing again, The Blue Sake Bomber lives!
    I installed a Vacuum gauge to see how much vacuum the DS pump is pulling. This is an Aviaid 2 stage DS pump, 5.5" Jones Racing serp pulley, Fluidamper crank pulley, Cosworth DS Pan, Peterson Vacuum Regulator. These pics are only under no load with no turbo boost blow by, so they aren't representative of what I'll see at the track, but I'm still very pleased with these numbers.

    Cold Idle right after startup, 13.5":



    Cold, 1,500 RPM, still 13"



    Warm, 3,500RPM, 13"- Excellent!



    Warm, 500-700 RPM Idle. The Vacuum drops to 1-2":



    And an engine shot as it stands today:



    I'll video the Vac gauge this weekend while racing so we can see the vac under full blow by race conditions.
    Last edited by Sgt.Gator; 05-16-2018 at 12:57 AM.
    "Good Judgement comes from Experience. Experience comes from Bad Judgement"
    Owner: Colonel Red Racing
    eBAy Store: http://stores.ebay.com/colonelredracing
    818R ICSCC SPM and HPDE Rental at Oregon Raceway Park
    2005 Subaru STI Race Car ICSCC ST and SPM, NASA ST3
    Palatov DP4 - ICSCC & SCCA Sports Racer and HPDE Rental at Oregon Raceway Park

  4. #724
    Tazio Nuvolari wannabe Scargo's Avatar
    Join Date
    Nov 2013
    Location
    south-central CT
    Posts
    1,566
    Post Thanks / Like
    Nice looking setup. I like how you have cool air directed onto the filter. What HP is it making? It looks like a smallish turbo in the stock location.
    I'm doing reversed NA intake on my '07 with GTX3576R, larger T04S frame with 4" inlet and 2.5" outlet, Tial 1.03 A/R housing with V-bands. Would be hard to do that DS setup the way I'm configuring it. Guess I could move the PS pump and put small alternator there.
    More pics or descriptions of the car? What class do you run?
    "Scotty, give me all the TRACTION she's got!" Pictures of what I drive till 818R is finished

  5. #725
    Sgt.Gator's Avatar
    Join Date
    Apr 2013
    Location
    Bend, Oregon
    Posts
    1,126
    Post Thanks / Like
    Quote Originally Posted by Scargo View Post
    Nice looking setup. I like how you have cool air directed onto the filter. What HP is it making? It looks like a smallish turbo in the stock location.
    I'm doing reversed NA intake on my '07 with GTX3576R, larger T04S frame with 4" inlet and 2.5" outlet, Tial 1.03 A/R housing with V-bands. Would be hard to do that DS setup the way I'm configuring it. Guess I could move the PS pump and put small alternator there.
    More pics or descriptions of the car? What class do you run?
    It's hard to do a reversed intake and do the DS pump on top; I don't think I've seen that done <yet!>

    My car is the blue #28, this pic is at the ICSCC race in Spokane last summer:



    The cool air duct is obviously a cut up stock inlet. What you can't see is that above and slightly behind the filter I have a small hood vent with a lip to pull air across the filter and out the engine bay. I'll post a pic below.

    I originally intended to race this car in the Thunderhill 25 Hour enduro. So I modded it with NASA ST3 / Thunderhill 25 E0 class as the goal and with lots of enduro mods like transmission cooler, power steering cooler, diff cooler ready to go (if needed, so far it's been ok temps), EWG turbo built into the turbo housing (No EWG pipe off the uppipe to crack a weld after 23 hours of non stop racing), Brake Fans, Coolant lines to the Tial EWG. Reality has set in and I realize I will never be a team owner taking this car to the 25 Hour. I'm working on other options to participate in some capacity there.

    I run 3 classes all in the ICSCC: ST (10lbs/hp); SPM (unlimited HP); and ME0 (Enduro class, unlimited HP). The turbo is small, the intent being to have lots of power under the curve. In ST3 type HP/Wt classes the goal is to hit MAX HP/TQ for your weight as soon as possible and hold a straight line across the RPM band at that level. Quick spooling smallish turbos work well for that. A high HP peak at high RPM is counterproductive. I have an ATP 3067 EWG turbo.
    These are last year's tunes with ported heads. This year with the rebuild I have oem heads which dropped the peak power about 10-20 HP/TQ. Which proves why ported heads are minimally cost effective until you get way up there in power goals.
    2017 Ported Heads: 295 HP / 289 TQ; 344 HP/ 357 TQ; and 355 HP/388 TQ.
    2018 OEM Heads: 277 HP/ 286 TQ; 323 HP/ 330 TQ; and 345 HP/ 375 TQ.

    If I quit doing ST HP/Wt racing I'd probably get an ATP 3076 EWG, It should be almost a straight swap. That would put me in the 400s easily.



    There's two threads on this car thru 3 owners on NASIOC:
    The original build: https://forums.nasioc.com/forums/sho....php?t=2035408
    My ownership: https://forums.nasioc.com/forums/sho....php?t=2836784

    Back to Dry Sumps and Oiling issues...
    Last edited by Sgt.Gator; 05-16-2018 at 12:49 PM.
    "Good Judgement comes from Experience. Experience comes from Bad Judgement"
    Owner: Colonel Red Racing
    eBAy Store: http://stores.ebay.com/colonelredracing
    818R ICSCC SPM and HPDE Rental at Oregon Raceway Park
    2005 Subaru STI Race Car ICSCC ST and SPM, NASA ST3
    Palatov DP4 - ICSCC & SCCA Sports Racer and HPDE Rental at Oregon Raceway Park

  6. #726
    Senior Member
    Join Date
    Jan 2014
    Location
    USA
    Posts
    540
    Post Thanks / Like
    Has anyone had a leak at the oil pickup area on the Aviaid pan? I can't tell if it's leaking at the bolts or the base of the fitting that meets the pan. I've inspected the o-ring and that looks good. Everything is nice an snug.

  7. #727
    Senior Member
    Join Date
    Jun 2015
    Posts
    652
    Post Thanks / Like
    Yes, bolts.

  8. #728
    Senior Member
    Join Date
    Jan 2014
    Location
    USA
    Posts
    540
    Post Thanks / Like
    Quote Originally Posted by RetroRacing View Post
    Yes, bolts.
    Thanks! Fixed with RTV?

  9. #729
    Moonlight Performance
    Hindsight's Avatar
    Join Date
    May 2014
    Location
    Atlanta
    Posts
    3,339
    Post Thanks / Like
    Quote Originally Posted by Sgt.Gator View Post
    2017 Ported Heads: 295 HP / 289 TQ; 344 HP/ 357 TQ; and 355 HP/388 TQ.
    2018 OEM Heads: 277 HP/ 286 TQ; 323 HP/ 330 TQ; and 345 HP/ 375 TQ.
    Thanks for sharing that - very good info. Who ported the heads? What cams? Same cams in both dyno tests?

  10. #730
    Senior Member Bob_n_Cincy's Avatar
    Join Date
    Sep 2012
    Location
    Cincinnati OH
    Posts
    3,391
    Post Thanks / Like
    Quote Originally Posted by Aero STI View Post
    Has anyone had a leak at the oil pickup area on the Aviaid pan? I can't tell if it's leaking at the bolts or the base of the fitting that meets the pan. I've inspected the o-ring and that looks good. Everything is nice an snug.
    I have a very small amount of oil seeping out between the pan and fitting. Not enough to leave a drip on the ground. See yellow circle in attached picture.
    also, I put studs in all pans parameter holes.

    Bob

    drip.jpg
    Last edited by Bob_n_Cincy; 06-08-2018 at 09:57 AM.
    818S #22 Candy Blue Frame, Front Gas Tank, 2.5L Turbo, Rear radiator, Shortened Transmission, Wookiee Compatible, Console mounted MR2 Shifter, Custom ECU panel, AWIC soon
    My Son Michael's Turbo ICE Build X22 http://thefactoryfiveforum.com/showt...rts-818S-Build
    My Electric Supercar Build X21 (on hold until winter) http://thefactoryfiveforum.com/showt...e-Build-Thread

  11. #731
    Sgt.Gator's Avatar
    Join Date
    Apr 2013
    Location
    Bend, Oregon
    Posts
    1,126
    Post Thanks / Like
    Quote Originally Posted by Hindsight View Post
    Thanks for sharing that - very good info. Who ported the heads? What cams? Same cams in both dyno tests?
    BuiltEJ Stage 2.5 heads. STI OEm cams both tests, same tuner, same dyno.

    The heads aren't listed on the website, but we came up with them after I called him. Easy to work with. I wanted more than Stage 2, but we both agreed that the +1mm valves were not needed that come with Stage 3, hence the stage 2.5.

    And I changed my mind on the next turbo, it will be a Gen 2 ATP 3576 EWG.
    "Good Judgement comes from Experience. Experience comes from Bad Judgement"
    Owner: Colonel Red Racing
    eBAy Store: http://stores.ebay.com/colonelredracing
    818R ICSCC SPM and HPDE Rental at Oregon Raceway Park
    2005 Subaru STI Race Car ICSCC ST and SPM, NASA ST3
    Palatov DP4 - ICSCC & SCCA Sports Racer and HPDE Rental at Oregon Raceway Park

  12. #732
    Moonlight Performance
    Hindsight's Avatar
    Join Date
    May 2014
    Location
    Atlanta
    Posts
    3,339
    Post Thanks / Like
    Cool thanks for the info.

    As for the ATP turbos - Is the one that you mention a stock-location turbo? Because I recall they had a stock location 7163 and it performed terribly compared to the main (rotated) version, according to all the dyno charts I saw.

  13. #733
    Sgt.Gator's Avatar
    Join Date
    Apr 2013
    Location
    Bend, Oregon
    Posts
    1,126
    Post Thanks / Like
    Quote Originally Posted by Hindsight View Post
    Cool thanks for the info.

    As for the ATP turbos - Is the one that you mention a stock-location turbo? Because I recall they had a stock location 7163 and it performed terribly compared to the main (rotated) version, according to all the dyno charts I saw.
    Stock location. Plug and play almost. I can basically pull my 3067 out and plug a 3576 in.
    "Good Judgement comes from Experience. Experience comes from Bad Judgement"
    Owner: Colonel Red Racing
    eBAy Store: http://stores.ebay.com/colonelredracing
    818R ICSCC SPM and HPDE Rental at Oregon Raceway Park
    2005 Subaru STI Race Car ICSCC ST and SPM, NASA ST3
    Palatov DP4 - ICSCC & SCCA Sports Racer and HPDE Rental at Oregon Raceway Park

  14. #734
    Senior Member Bob_n_Cincy's Avatar
    Join Date
    Sep 2012
    Location
    Cincinnati OH
    Posts
    3,391
    Post Thanks / Like

    Oil filling crankcase when 818 not used for more than a couple months.

    My 818 has an Aviaid dry sump system. It has 2 external scavenge pumps and uses the OEM oil pump.

    drysump.jpg

    Twice while the car sat without starting the engine for 3+ months, the oil from the tank filled the crankcase. This last time, I believe it was high enough in the block to get past the piston rings and fill the exhaust manifold. When starting, the car smoked badly for 5 to 10 minutes.

    Has anyone else seen this with a dry sump system on a flat engine?
    Bob
    Last edited by Bob_n_Cincy; Today at 09:21 AM.
    818S #22 Candy Blue Frame, Front Gas Tank, 2.5L Turbo, Rear radiator, Shortened Transmission, Wookiee Compatible, Console mounted MR2 Shifter, Custom ECU panel, AWIC soon
    My Son Michael's Turbo ICE Build X22 http://thefactoryfiveforum.com/showt...rts-818S-Build
    My Electric Supercar Build X21 (on hold until winter) http://thefactoryfiveforum.com/showt...e-Build-Thread

  15. #735
    Senior Member
    Join Date
    Jun 2013
    Location
    Bowling Green, KY
    Posts
    1,128
    Post Thanks / Like
    I don't have experience with drain back on a boxer engine but can see it happening. Bob what I have done on engines I have had with a DS system is remove the belt and spin the pump over with a small electric motor. In my case it was to prime the engine before starting. For the 2 stage scavage system like the Element kit it would work evacuate the crankcase, I don't know if you could get enough oil in a cylinder to hydra lock the engine but something to consider. I would think the height of the oil tank will have an effect on the drain back as well.

  16. #736
    Member
    Join Date
    Sep 2012
    Location
    DFW, Texas
    Posts
    60
    Post Thanks / Like
    Quote Originally Posted by Bob_n_Cincy View Post
    My 818 has an Aviaid dry sump system. It has 2 external scavenge pumps and uses the OEM oil pump.

    drysump.jpg

    Twice while the car sat without starting the engine for 3+ months, the oil from the tank filled the crankcase. This last time, I believe it was high enough in the block to get past the piston rings and fill the exhaust manifold. When starting, the car smoked badly for 5 to 10 minutes.

    Has anyone else seen this with a dry sump system on a flat engine?
    Bob
    I was just about to post a similar issue. I did a first start two months ago, then let it sit, it's been seeping oil on the floor from what I think is the cam seals. The sump tank is very low now, but I bet the cylinders are filled with oil, too. I think this is just an inherent problem with dry sump systems. After talking with some other people, it seems dry sumps will eventually do this the only option is to put a shut off valve in the feed line (I don't know if I like this idea) or to drain the oil if you know it will be sitting for a bit (Apparently, a lot of race teams do this).

  17. #737
    Tazio Nuvolari wannabe Scargo's Avatar
    Join Date
    Nov 2013
    Location
    south-central CT
    Posts
    1,566
    Post Thanks / Like
    I don't have a DS system yet... but it seems if you had enough wear in the oil pump then this would be more likely to happen.
    "Scotty, give me all the TRACTION she's got!" Pictures of what I drive till 818R is finished

  18. #738
    Sgt.Gator's Avatar
    Join Date
    Apr 2013
    Location
    Bend, Oregon
    Posts
    1,126
    Post Thanks / Like
    I've had this problem. I tried attaching a electric drill to the end of the Aviaid pump shaft to scavenge the pan. Mistake, I caused the shaft to go goofy and had to send it back to Aviaid for a rebuild.

    Th Cosworth Instructions say: "Note: If the engine will go for an extended period of time without running, it is possible for oil to migrate from the oil tank into the sump. It is necessary to scavenge the engine prior to start up to avoid potential engine damage. This can be done by removing the drive belt and spinning the pump by hand until the sump is dry. Verify that there is no standing oil in the sump by checking the oil tank level."

    So now if it's been a long time or the level in the DS tank looks low, I spin it by hand.
    "Good Judgement comes from Experience. Experience comes from Bad Judgement"
    Owner: Colonel Red Racing
    eBAy Store: http://stores.ebay.com/colonelredracing
    818R ICSCC SPM and HPDE Rental at Oregon Raceway Park
    2005 Subaru STI Race Car ICSCC ST and SPM, NASA ST3
    Palatov DP4 - ICSCC & SCCA Sports Racer and HPDE Rental at Oregon Raceway Park

  19. Thanks Zach34 thanked for this post
    Likes Zach34 liked this post
  20. #739
    Senior Member Bob_n_Cincy's Avatar
    Join Date
    Sep 2012
    Location
    Cincinnati OH
    Posts
    3,391
    Post Thanks / Like
    Quote Originally Posted by Mitch Wright View Post
    I don't know if you could get enough oil in a cylinder to hydra lock the engine but something to consider. I would think the height of the oil tank will have an effect on the drain back as well.
    Mitch, The level of the oil in my tank is about at the top of the block. I am very worried about hydra lock. I smashed a rod bearing in my 64 Chevelle sbc by hydra lock.

    Quote Originally Posted by NevaLift2Shift View Post
    I was just about to post a similar issue. I did a first start two months ago, then let it sit, it's been seeping oil on the floor from what I think is the cam seals. The sump tank is very low now, but I bet the cylinders are filled with oil, too. I think this is just an inherent problem with dry sump systems. After talking with some other people, it seems dry sumps will eventually do this the only option is to put a shut off valve in the feed line (I don't know if I like this idea) or to drain the oil if you know it will be sitting for a bit (Apparently, a lot of race teams do this).
    NevaLift2Shift, Pull the plugs, then crank it over to get the oil out of the cylinders.
    I think I will put a shut of valve on the dry sump tank and hang a "remove before flight" tag on it. tag.jpg

    Quote Originally Posted by Scargo View Post
    I don't have a DS system yet... but it seems if you had enough wear in the oil pump then this would be more likely to happen.
    Scargo, I think with enough time, oil will seep through any tolerance gap. That said, my pump is OEM with over 100k on it. Thanks Scargo.


    Quote Originally Posted by Sgt.Gator View Post
    I've had this problem. I tried attaching a electric drill to the end of the Aviaid pump shaft to scavenge the pan. Mistake, I caused the shaft to go goofy and had to send it back to Aviaid for a rebuild.
    The Cosworth Instructions say: "Note: If the engine will go for an extended period of time without running, it is possible for oil to migrate from the oil tank into the sump. It is necessary to scavenge the engine prior to start up to avoid potential engine damage. This can be done by removing the drive belt and spinning the pump by hand until the sump is dry. Verify that there is no standing oil in the sump by checking the oil tank level."
    So now if it's been a long time or the level in the DS tank looks low, I spin it by hand.

    Gator, in the 818, the pulley shaft is to close to attach a drill motor. Thanks for the Cosworth info. It tells me this is a side effect of a dry sump system I was not aware of.


    Thanks All
    Bob
    818S #22 Candy Blue Frame, Front Gas Tank, 2.5L Turbo, Rear radiator, Shortened Transmission, Wookiee Compatible, Console mounted MR2 Shifter, Custom ECU panel, AWIC soon
    My Son Michael's Turbo ICE Build X22 http://thefactoryfiveforum.com/showt...rts-818S-Build
    My Electric Supercar Build X21 (on hold until winter) http://thefactoryfiveforum.com/showt...e-Build-Thread

  21. Thanks Zach34 thanked for this post
    Likes Zach34 liked this post
Page 19 of 19 FirstFirst ... 9171819

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Stewart Transport

Visit our community sponsor