Oil starvation problem at high rpm
04-25-2010, 01:13 PM
#106
Rennlist Member
The solution is AMSOIL, and taking the breathers and just give them a little more upward bends, so that the condensed vapors just return back to the valve cover and oil filler path to the pan. has anyone seen my videos?I have front and rear views. I dont burn or use any oil , I wrap the engine to near redline on every shift and have over 200races, plus more if you count the engines I support with fellow racer Scot.
(now scot has a little blow by issue, but we are going to fix that with hose position or the old catch can set up .
)
No breather, baffle, spacers, vents, hoses, accusump, oil cooler, anything. all stock and it works well!
How many of these guys are at the track having all sorts of breather issues and leaks, fires, and end up going home?
and, mobil 1 turns to water if you use it on a race track , or a real hot day.
Mk
(now scot has a little blow by issue, but we are going to fix that with hose position or the old catch can set up .
)No breather, baffle, spacers, vents, hoses, accusump, oil cooler, anything. all stock and it works well!
How many of these guys are at the track having all sorts of breather issues and leaks, fires, and end up going home?
and, mobil 1 turns to water if you use it on a race track , or a real hot day.
Mk
04-25-2010, 03:50 PM
#108
04-26-2010, 12:57 AM
#109
Rennlist Member
Oh yeah, I'm just charmed! 
I have a spare rabbit foot if you want them, since you are such a believer in luck and probably the tooth fairy I imagine too. 200 race days, no oil issues, 4 different engines and 928 platforms. Hmmmm, maybe you should try it!
mk
I have a spare rabbit foot if you want them, since you are such a believer in luck and probably the tooth fairy I imagine too. 200 race days, no oil issues, 4 different engines and 928 platforms. Hmmmm, maybe you should try it!
mk
04-26-2010, 01:26 AM
#110
Race Director
Since I resurrected this thread here is my .02
1: There is numerous design FLAWS in the 928 oiling system
1a: These are only apparent under track conditions at sustained high RPM (with corners NOT ORR)
2: The oil starvation problem is common to many wetsump track driven cars, not just 928's..
3: It appears the magic "RPM" limit is around 6,000rpm...above that oil consumptions goes up
Running a quality oil HELPS....yes Amsoil is good, but so is Royal Purple or Redline...
Yes there are some track driven 928's that are entirely stock (think MK) that live a long life...but there are FAR MORE that die a classic 2-6 starvation death....dry sump is the best, but pricey option....it appears a good low cost solution is an accusump, retro oil pan + spacer or both....
Speaking as the owner of track driven 928's that have died on track between 10-16 hours with the stock (S4 style) system vs the Lemons (3/8th spacer with a retro oil pan) that has over 43 hours on track with GREAT OIL PRESSURE & it doesn't even have an oil cooler!!!
One glaring weakness in this debate is DATA...other than blown engines....we really need an dedicated oil pressure gauge installed in an otherwise stock car to see the true drops...since the stock gauge is iffy at best... I have video after video of the lemons racer on street tires and R comps taking corners at over 1g where you can SEE the oil temp and pressure.... We need MK to find a way to link a Gopro to his stock pressure gauge AND an autometer to see the differences....
1: There is numerous design FLAWS in the 928 oiling system
1a: These are only apparent under track conditions at sustained high RPM (with corners NOT ORR)
2: The oil starvation problem is common to many wetsump track driven cars, not just 928's..
3: It appears the magic "RPM" limit is around 6,000rpm...above that oil consumptions goes up
Running a quality oil HELPS....yes Amsoil is good, but so is Royal Purple or Redline...
Yes there are some track driven 928's that are entirely stock (think MK) that live a long life...but there are FAR MORE that die a classic 2-6 starvation death....dry sump is the best, but pricey option....it appears a good low cost solution is an accusump, retro oil pan + spacer or both....
Speaking as the owner of track driven 928's that have died on track between 10-16 hours with the stock (S4 style) system vs the Lemons (3/8th spacer with a retro oil pan) that has over 43 hours on track with GREAT OIL PRESSURE & it doesn't even have an oil cooler!!!
One glaring weakness in this debate is DATA...other than blown engines....we really need an dedicated oil pressure gauge installed in an otherwise stock car to see the true drops...since the stock gauge is iffy at best... I have video after video of the lemons racer on street tires and R comps taking corners at over 1g where you can SEE the oil temp and pressure.... We need MK to find a way to link a Gopro to his stock pressure gauge AND an autometer to see the differences....
04-26-2010, 04:06 AM
#111
Rennlist Member
Ive stared at my oil gauge for a lap only a second off my pace, and thats 10 seconds faster a lap than the lemons car on DOTs. Its pegged at 5 bar, except for turn 2 at Thill and only for that turn its at 4.5bar and no lower.
I shift at well over 6000rpm on all my racing shifts, unless im grip limited, which is very unusual.
Its not the dry sump that solves the problem, its the drilled crank.
As far as other race track driven 928s that have blown, think about this.... many of them before they blew, could have easily been damaged before their track duty scots was an unknown that lasted one day before it grenaded. with a known engine, (one that was taken apart , refreshed and installed) its never had any issues. *he had two of those and both replacements had now issues for a lot of racing ). Your "Widow" came from suspect history. Andersons failure in constantines racer, ran mobile 1. others, im sure we could find that had suspect mods that could have contributed to oil starvation. Lots of theories out there, but again, I dont think Im lucky. I keep the oil full, I shift at 6500rpm, and dont run around sweepers at costant high rpm, and dont sacrafice speed or lap time, by doing so. I dont over rev the motor and try and be smooth.
There could be some differences on the tracks I visit, but I dont think any of them are that much different, except, I dont visit Willow springs that often anymore and I bet that track could cause my stock set up some problems, depending on my speed and rpm around turn 8-9.
mk
I shift at well over 6000rpm on all my racing shifts, unless im grip limited, which is very unusual.
Its not the dry sump that solves the problem, its the drilled crank.
As far as other race track driven 928s that have blown, think about this.... many of them before they blew, could have easily been damaged before their track duty scots was an unknown that lasted one day before it grenaded. with a known engine, (one that was taken apart , refreshed and installed) its never had any issues. *he had two of those and both replacements had now issues for a lot of racing ). Your "Widow" came from suspect history. Andersons failure in constantines racer, ran mobile 1. others, im sure we could find that had suspect mods that could have contributed to oil starvation. Lots of theories out there, but again, I dont think Im lucky. I keep the oil full, I shift at 6500rpm, and dont run around sweepers at costant high rpm, and dont sacrafice speed or lap time, by doing so. I dont over rev the motor and try and be smooth.
There could be some differences on the tracks I visit, but I dont think any of them are that much different, except, I dont visit Willow springs that often anymore and I bet that track could cause my stock set up some problems, depending on my speed and rpm around turn 8-9.
mk
Since I resurrected this thread here is my .02
1: There is numerous design FLAWS in the 928 oiling system
1a: These are only apparent under track conditions at sustained high RPM (with corners NOT ORR)
2: The oil starvation problem is common to many wetsump track driven cars, not just 928's..
3: It appears the magic "RPM" limit is around 6,000rpm...above that oil consumptions goes up
Running a quality oil HELPS....yes Amsoil is good, but so is Royal Purple or Redline...
Yes there are some track driven 928's that are entirely stock (think MK) that live a long life...but there are FAR MORE that die a classic 2-6 starvation death....dry sump is the best, but pricey option....it appears a good low cost solution is an accusump, retro oil pan + spacer or both....
Speaking as the owner of track driven 928's that have died on track between 10-16 hours with the stock (S4 style) system vs the Lemons (3/8th spacer with a retro oil pan) that has over 43 hours on track with GREAT OIL PRESSURE & it doesn't even have an oil cooler!!!
One glaring weakness in this debate is DATA...other than blown engines....we really need an dedicated oil pressure gauge installed in an otherwise stock car to see the true drops...since the stock gauge is iffy at best... I have video after video of the lemons racer on street tires and R comps taking corners at over 1g where you can SEE the oil temp and pressure.... We need MK to find a way to link a Gopro to his stock pressure gauge AND an autometer to see the differences....
1: There is numerous design FLAWS in the 928 oiling system
1a: These are only apparent under track conditions at sustained high RPM (with corners NOT ORR)
2: The oil starvation problem is common to many wetsump track driven cars, not just 928's..
3: It appears the magic "RPM" limit is around 6,000rpm...above that oil consumptions goes up
Running a quality oil HELPS....yes Amsoil is good, but so is Royal Purple or Redline...
Yes there are some track driven 928's that are entirely stock (think MK) that live a long life...but there are FAR MORE that die a classic 2-6 starvation death....dry sump is the best, but pricey option....it appears a good low cost solution is an accusump, retro oil pan + spacer or both....
Speaking as the owner of track driven 928's that have died on track between 10-16 hours with the stock (S4 style) system vs the Lemons (3/8th spacer with a retro oil pan) that has over 43 hours on track with GREAT OIL PRESSURE & it doesn't even have an oil cooler!!!
One glaring weakness in this debate is DATA...other than blown engines....we really need an dedicated oil pressure gauge installed in an otherwise stock car to see the true drops...since the stock gauge is iffy at best... I have video after video of the lemons racer on street tires and R comps taking corners at over 1g where you can SEE the oil temp and pressure.... We need MK to find a way to link a Gopro to his stock pressure gauge AND an autometer to see the differences....
04-26-2010, 07:12 PM
#112
Race Director
Oil level is a contributing factor...no doubt about that....the stock breather injecting oil into the intake doesn't help keep the oil level high either....
I'd like to ride in your racer just to watch the pressure gauge....but a real autometer gauge is better...
Maybe Friday with NCRC? The weather looks good? I'm thinking about racing with them...you should come out!
I'd like to ride in your racer just to watch the pressure gauge....but a real autometer gauge is better...
Maybe Friday with NCRC? The weather looks good? I'm thinking about racing with them...you should come out!
04-27-2010, 01:22 AM
#113
Man of many SIGs
Rennlist Member
Rennlist Member
The solution set has been expanded to include a commercially-available windage and scraper set from Ishihara-Johnson.I-J Scrapers More racers are using dry sump systems. There's still not a commercial option for that. Each one is custom. 928 Specialists offer a separator for the blow-by which is popular. Some guys are using an accusump as well. A solid solution is dry sump with drilled crank. Each owner seems to have his own set-up.
There are a few other long, involved and vigorous discussion on bearing failure, crank drilling, dry sumps and windage systems. Look for those.
There are a few other long, involved and vigorous discussion on bearing failure, crank drilling, dry sumps and windage systems. Look for those.
