Michael Knight
Totally Hooked
- Thread starter
- #81
flaps felt kind of sturdy but who knows how long they last.
GR Yaris GR Yaris and oil pressure (in track use)
- Thread starter Michael Knight
- Start date
there is a couple of people (including me, and I am at 34k miles with ~2k track miles) who regularly overfill by 0.4-0.5 litres with no issues, my Toyota service is aware and approves.
My guess is it helps more on keeping the temps a few percent down and I haven't got a <1bar oil pressure yet, but it sure doesn't solve the issue.
Are you using wider/more sticky tires on track?
Maybe time to make a poll?
- Overfill tracking - no related issues
- Overfill no tracking - no related issues
- Overfill - issues, please comment
- No overfill - issues with oil/pressure, please comment
Something like that?
Michael Knight
Totally Hooked
- Thread starter
- #84
also add track and tyre variables.
just kidding but they do play a role in terms of how many G's are generated.
I think Toyota accepting overfill is kind of strange as manual states clearly there should not be overfill. so they are kind of voiding their own instructions in the manual.
doabackflip
Devoted member
I should have said, I already have the baffled sump, and sticky 255/35 a052 tyres. I was having issues, so I overfilled by half a litre, and it was fine for a few hours, then the syvecs tripped again later in the day, so I gave up and went home. I don’t know if I was getting faster during the day or if it had blown some oil out, so I have a catch can now to see if that was what happened. I didn’t have a laptop with me, and the syvecs had overwritten its logs by the time I got home. There is a 5w40 api sp option which I am considering, but I might just change one thing at a time, and take the laptop with me so I can look at the logs. I have an oil cooler and big intercooler, and no temp issues.
Michael Knight
Totally Hooked
- Thread starter
- #86
Some additional topics to consider - bearing clearances in the engine.
the thinner the oil, the less hp loss and better cooling.
what is the main and conrod bearing clearance for GR in standard size?
Didnt remember car has aluminum pistons and aluminum crankshaft bearings. Pretty epic.
This had some data in it - std clearance 0.012-0.016 then?
Specifications for STD size only
Similar chart for std rod bearing
3B8532H-STD
Specifications for STD size only
the thinner the oil, the less hp loss and better cooling.
what is the main and conrod bearing clearance for GR in standard size?
Didnt remember car has aluminum pistons and aluminum crankshaft bearings. Pretty epic.
This had some data in it - std clearance 0.012-0.016 then?
Specifications for STD size only
| Sizes | STD, .025, .25 |
| Oil Clearance | |
| Half Type | Upper & lower |
| Material | F780 |
| Min. Std Shaft Size | 55,988 mm / 2.2042 in |
| Max. Std Shaft Size | 56 mm / 2.2047 in |
| Min. Std Tunnel Size | 60 mm / 2.3622 in |
| Max. Std Tunnel Size | 60,016 mm / 2.3628 in |
| Max Wall at Crown | 2,002 mm / 0.0788 in |
| Max Overall Length | 17,25 mm / 0.6791 in |
Similar chart for std rod bearing
3B8532H-STD
Specifications for STD size only
| Sizes | STD, .025, .25 |
| Oil Clearance | |
| Half Type | Identical halves |
| Material | F781 |
| Min. Std Shaft Size | 47,992 mm / 1.8894 in |
| Max. Std Shaft Size | 48 mm / 1.8898 in |
| Min. Std Tunnel Size | 51 mm / 2.0079 in |
| Max. Std Tunnel Size | 51,024 mm / 2.0088 in |
| Max Wall at Crown | 1,496 mm / 0.0589 in |
| Max Overall Length | 17,25 mm / 0.6791 in |
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Good find!
One thing though, not really saying why thicker oil can dissipate less heat, it reads as an inherent property?
To my understanding, thicker oil will heat up more because of the higher internal friction, also manifested in the higher oil pressure (=more power put into the oil by the oil pump at similar flow*), and hotter oil can obviously cool less as there is less temperature delta. And so, in part, nullifies the reason to go thicker in the first place as being hotter will reduce viscosity.
So as before, going thicker isn't a very good solution in solving high oil temp issues...
*Here assuming the actual flow rate isn't reduced which makes sense as the oil pump will be more effective on higher viscosity, while at the same time flow losses increase too, evening things out more or less flowwise but resulting in a higher overall pressure.
One thing though, not really saying why thicker oil can dissipate less heat, it reads as an inherent property?
To my understanding, thicker oil will heat up more because of the higher internal friction, also manifested in the higher oil pressure (=more power put into the oil by the oil pump at similar flow*), and hotter oil can obviously cool less as there is less temperature delta. And so, in part, nullifies the reason to go thicker in the first place as being hotter will reduce viscosity.
So as before, going thicker isn't a very good solution in solving high oil temp issues...
*Here assuming the actual flow rate isn't reduced which makes sense as the oil pump will be more effective on higher viscosity, while at the same time flow losses increase too, evening things out more or less flowwise but resulting in a higher overall pressure.
GR- FOUR
Absorbed member
- Mar 20, 2024
- 43
- 67
Really interested in this problem with the G16-GTS engine and oil pressure issues.
The baffled sump design from Lamspeed looks fine, not sure about the rubber trap doors ?
My thoughts are would it be possible to add a 10 or 15mm billet sump packer to gain oil capacity with longer bolts, obviously you then need extend the oil pick - up the same amount and the same with the baffles if that's possible .
I ' ve also read on a previous thread that the oil pump is running lower pressure than most other engines, can this be increased as some of this pressure is going to the Piston cooling jets as these are quite large.
I do watch a channel called oil geek on YT, and he is a mine of information, stating oil overfill is not a good idea and showing results on a Dyno engine, it is american based but all his analysis is valid and he is thorough .
I must admit with all Toyotas development on this car and engine that it has no baffle or windage tray, knowing this is going to be tracked by a lot of people .
Regards Russ...
The baffled sump design from Lamspeed looks fine, not sure about the rubber trap doors ?
My thoughts are would it be possible to add a 10 or 15mm billet sump packer to gain oil capacity with longer bolts, obviously you then need extend the oil pick - up the same amount and the same with the baffles if that's possible .
I ' ve also read on a previous thread that the oil pump is running lower pressure than most other engines, can this be increased as some of this pressure is going to the Piston cooling jets as these are quite large.
I do watch a channel called oil geek on YT, and he is a mine of information, stating oil overfill is not a good idea and showing results on a Dyno engine, it is american based but all his analysis is valid and he is thorough .
I must admit with all Toyotas development on this car and engine that it has no baffle or windage tray, knowing this is going to be tracked by a lot of people .
Regards Russ...
- Dec 21, 2021
- 134
- 497
I have perhaps a basic question for someone who knows more than I, when doing time attack I'm seeing the oil pressure drop as low as 0.8bar for a fraction of a second (at low rpm not high) typically when starting a cooldown lap and I might dip the clutch to let the revs drop while I jump up a few gears from say 3rd to 6th gear. Since I noticed that happening on my alarms (I have an OBD device that plugs in) I have stopped doing it, however my question is, under low load and rpm, is oil pressure as low as an 0.8 bar dip before it bounces back to over 1bar going to cause damage?
Gr Yaris cup cars on certain countries run without baffled sump with no issues, on rally stages and also have done loads of on track testing… on rally slicks.
I’m not sure fitting a baffled sump will really help reliability or otherwise, specially when they still ask you to overfill.
I’m not sure fitting a baffled sump will really help reliability or otherwise, specially when they still ask you to overfill.
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Could be also interesting option, but maybe overfill is enough.
Accusump Oil Accumulators - how do they work?
Quality parts, spares & racewear for all Motorsport needs. Huge stocks supplied worldwide. Fast delivery. Professional service. Call us for technical helpwww.merlinmotorsport.co.uk
I know this is an old thread, but sorry for digging up, I only came it across it the other day. Very interesting inputs from various knowledgeable people here, appreciated.
All this to say that I have an accusump on my track car which is equipped with an Hayabusa engine without a baffled sump. It's much cheaper than a dry sump system and works really well. When the oil pressure from the engine oil pump drops lower than the pressurized air in the accusump (I set it to 1.8 bars in mine), the accusump releases it's oil, thus lubricating the engine until the engine's oil pump can catch oil again to do it's job,. Max time it can release oil, is approx 20s but that figure increases with the larger capacity ones.
I'm not sure where an accusump could be conveniently installed in the GRY engine bay, I see only above the GB, under & in front of the air box. And even so, seems a bit tight. Other option would be to run the hose all the way to the rear and install the accusump in the boot.
Michael Knight
Totally Hooked
- Thread starter
- #92
accusump can take away critical psi when on power so not sure if that's best option either. It needs to get its pressure somewhere.
- Dec 27, 2021
- 1,738
- 2,880
My understanding is that you can configure it to only fill at a specific pressure/rate. Something like 3.7 bar vs 4.0 bar when you are at WOT isn’t going to make any difference.
Yes & no. Once it's filled with oil, especially cold, that reserve 1 liter oil is stored @6 to 7 bars. (Pressure reading on the air side of the accusump, not the oil side of the piston ofcourse)
Yes, there has to be that first time to fill & pressurize it, (only takes a few seconds) and that's at every oil change, where you overfill to compensate the volume of your accusump, in my case 4 liters for the Busa engine + 1 liter for the accusump. Those few seconds could be the moment where less oil pressure is reaching the top engine because of the accusump taking away pressure generated by the oil pump. Is that what you meant @Michael Knight ?
But this is not at high power, it's only on start up, and remember, at that moment your sump is over filled, your engine is still warm with oil everywhere because it ran until warm prior to the oil change.
When the engine is shut off, the valve closes (if electronic) and keeps the oil in the accusump, at the pressure the oil pump was giving at idle or a little higher if you choose to do so.
No, because once you switch on the ignition, the contact toggle switch or whatnot (depends on how you wired it to energize the valve), when that valve opens, the accusump having a positive pressure in it, releases it's oil through the engine, thus pre-lubricating it, before you start the engine. Nothing obliges you to start the engine before the 20s or so of prelubrification is depleted, thus the oil pump taking over to re-establish normal oil pressure in the engine, and refilling the accusump until the pressures between the air side of the accusump and the engine lube oil pump equalize.
At high RPM, the oil pump delivers approx 6-7 bars @ 10 000 RPM, heaps enough for the accusump to stay full and the orignal 4 liters of oil circulating in the engine.
Ofcourse, each down shift results in lesser RPM for a second or so then rev-matching increases again the RPM and as the RPM goes up & down around the track, the accusump releases and absorbs oil non stop due to oil pressure equalizing.
If for some reason (track configuration heavy braking point, long curve, anything generating high G-forces possibly resulting in moments of oil starvation and the oil pressure were to drop below the set pressure, the accusump will release all it's oil to compensate for the oil pump for 20s or so. If the oil starvation were to last longer than that, then yes, possible damage to the engine may occur I suppose.
Anyhow, I've been hammering this car on track since 2015, and haven't had any issues whatsoever with the engine so far.
I agree that we can't compare a 1340cc NA four cylinder engine with max RPM @ 11000 RPM to the GRY engine. Obviously, more data will be needed before installing an accusump on the GRY, especially oil pressures from the oil pump and how much air pressure to initially set in the accusump for it to work efficiently.
Hope no one fell asleep !
Yes, there has to be that first time to fill & pressurize it, (only takes a few seconds) and that's at every oil change, where you overfill to compensate the volume of your accusump, in my case 4 liters for the Busa engine + 1 liter for the accusump. Those few seconds could be the moment where less oil pressure is reaching the top engine because of the accusump taking away pressure generated by the oil pump. Is that what you meant @Michael Knight ?
But this is not at high power, it's only on start up, and remember, at that moment your sump is over filled, your engine is still warm with oil everywhere because it ran until warm prior to the oil change.
When the engine is shut off, the valve closes (if electronic) and keeps the oil in the accusump, at the pressure the oil pump was giving at idle or a little higher if you choose to do so.
No, because once you switch on the ignition, the contact toggle switch or whatnot (depends on how you wired it to energize the valve), when that valve opens, the accusump having a positive pressure in it, releases it's oil through the engine, thus pre-lubricating it, before you start the engine. Nothing obliges you to start the engine before the 20s or so of prelubrification is depleted, thus the oil pump taking over to re-establish normal oil pressure in the engine, and refilling the accusump until the pressures between the air side of the accusump and the engine lube oil pump equalize.
At high RPM, the oil pump delivers approx 6-7 bars @ 10 000 RPM, heaps enough for the accusump to stay full and the orignal 4 liters of oil circulating in the engine.
Ofcourse, each down shift results in lesser RPM for a second or so then rev-matching increases again the RPM and as the RPM goes up & down around the track, the accusump releases and absorbs oil non stop due to oil pressure equalizing.
If for some reason (track configuration heavy braking point, long curve, anything generating high G-forces possibly resulting in moments of oil starvation and the oil pressure were to drop below the set pressure, the accusump will release all it's oil to compensate for the oil pump for 20s or so. If the oil starvation were to last longer than that, then yes, possible damage to the engine may occur I suppose.
Anyhow, I've been hammering this car on track since 2015, and haven't had any issues whatsoever with the engine so far.
I agree that we can't compare a 1340cc NA four cylinder engine with max RPM @ 11000 RPM to the GRY engine. Obviously, more data will be needed before installing an accusump on the GRY, especially oil pressures from the oil pump and how much air pressure to initially set in the accusump for it to work efficiently.
Hope no one fell asleep !
Michael Knight
Totally Hooked
- Thread starter
- #95
Yes that was the concernYes & no. Once it's filled with oil, especially cold, that reserve 1 liter oil is stored @6 to 7 bars. (Pressure reading on the air side of the accusump, not the oil side of the piston ofcourse)
Yes, there has to be that first time to fill & pressurize it, (only takes a few seconds) and that's at every oil change, where you overfill to compensate the volume of your accusump, in my case 4 liters for the Busa engine + 1 liter for the accusump. Those few seconds could be the moment where less oil pressure is reaching the top engine because of the accusump taking away pressure generated by the oil pump. Is that what you meant @Michael Knight ?
But this is not at high power, it's only on start up, and remember, at that moment your sump is over filled, your engine is still warm with oil everywhere because it ran until warm prior to the oil change.
When the engine is shut off, the valve closes (if electronic) and keeps the oil in the accusump, at the pressure the oil pump was giving at idle or a little higher if you choose to do so.
No, because once you switch on the ignition, the contact toggle switch or whatnot (depends on how you wired it to energize the valve), when that valve opens, the accusump having a positive pressure in it, releases it's oil through the engine, thus pre-lubricating it, before you start the engine. Nothing obliges you to start the engine before the 20s or so of prelubrification is depleted, thus the oil pump taking over to re-establish normal oil pressure in the engine, and refilling the accusump until the pressures between the air side of the accusump and the engine lube oil pump equalize.
At high RPM, the oil pump delivers approx 6-7 bars @ 10 000 RPM, heaps enough for the accusump to stay full and the orignal 4 liters of oil circulating in the engine.
Ofcourse, each down shift results in lesser RPM for a second or so then rev-matching increases again the RPM and as the RPM goes up & down around the track, the accusump releases and absorbs oil non stop due to oil pressure equalizing.
If for some reason (track configuration heavy braking point, long curve, anything generating high G-forces possibly resulting in moments of oil starvation and the oil pressure were to drop below the set pressure, the accusump will release all it's oil to compensate for the oil pump for 20s or so. If the oil starvation were to last longer than that, then yes, possible damage to the engine may occur I suppose.
Anyhow, I've been hammering this car on track since 2015, and haven't had any issues whatsoever with the engine so far.
I agree that we can't compare a 1340cc NA four cylinder engine with max RPM @ 11000 RPM to the GRY engine. Obviously, more data will be needed before installing an accusump on the GRY, especially oil pressures from the oil pump and how much air pressure to initially set in the accusump for it to work efficiently.
Hope no one fell asleep !
BarShushan
New member
- Apr 8, 2024
- 20
- 6
how's the oil temps after changing to 5/30?
did you change to 5/30 before putting an oil cooler?
BarShushan
New member
- Apr 8, 2024
- 20
- 6
Have you find anything that says it helps with oil pressure?Pardon my ignorance, but noticed the pan was revised, not sure if it has anything to do with oil pressure though?
View attachment 19239View attachment 19240
Seems the 12101-18050 is 50% more expensive at Toyota
Michael Knight
Totally Hooked
- Thread starter
- #98
assuming the pan is close to same form finding it quite difficult to believe it would make any difference. its the problem of oil pickup + actual oil chamber where the pan itself does little if the form is the same.
This should help
Lamspeed Racing Toyota GR Yaris / Corolla G16E-GTS Baffled Oil Pan
Details: It's been a long time coming, but it is here! Developed by NA Autosport exclusively for us at Lamspeed Racing. These are essential any type of racing in general where you have high lateral G forces and are hard on the brakes. A common issue on the G16E-GTS is low oil pressure under hard...
lamspeedracing.com
Michael Knight
Totally Hooked
- Thread starter
- #100
I didn't see similar pressure drops on track with baffles installed. my camera angle was not best so can do the retest next week thu once back on race track.This should help
but didnt see any testing results yetLamspeed Racing Toyota GR Yaris / Corolla G16E-GTS Baffled Oil Pan
Details: It's been a long time coming, but it is here! Developed by NA Autosport exclusively for us at Lamspeed Racing. These are essential any type of racing in general where you have high lateral G forces and are hard on the brakes. A common issue on the G16E-GTS is low oil pressure under hard...
