Just stumbled upon this random piece of information - the M4 GTS has increased oil quantity:
Yeah, basically overfill the pan by 1/2qt when racing lol.
It finally stopped raining and I was able to get out to run another autocross yesterday with some sticky Hoosier A7 (17/225's). No Accusump installed. I have been messing with a few things and didn't have time to re-install it. The results were not good... I don't have any video since I was getting data, but, there are multiple points in the log where I was seeing low 20's psi oil pressure. As posted earlier, anything over 3,000rpm and I should be seeing 60psi still. This screenshot below was a sweeping left hand turn. I saw a minimum of 26.5psi and then again in a sweeping right hand turn I was seeing as low as 23.5psi.
I came in 9/77 overall in terms of raw time which was about 1s off the FTD times of the Street modified Subaru drivers that are all on Hoosier's as well. I was really in 6/77 if you don't count the 2-stroke F1 car that 3 different people were sharing. No chance of ever beating their times.
I think I am going to go change my oil and look for metal LOL
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screaminfast
Sergeant
I LOVE the accusump idea. I think I might incorporate that into my build. I didn't even realize that the N54's didn't have oil pressure sensors. I think I'll be adding that to my gauge pack as well. Is it overkill to do a pump from front of pan to rear in addition to accusump? Would I be ok with just an accusump plumbed in? I really like the idea of cold start-oiling. My car is mostly a fun highway car with occasional drag/drift days and some HPDE's.
There is a guy at autocross that races a classic mustang. Like, full-blown prep. He runs an Accusump. The guy who runs the race shop who builds his engines was actually there yesterday hanging out...
I asked them both just how much I should rely on the Accusump as I am seeing signs of oil starvation without it installed. They both swore by using it. He says they've been using them at the drag strip for decades. He was telling me about how the old closed-down drag strip out here on long island used to have a sharp right-hand bend at the end of the run-off that old school hot-rods would oil starve on. The pans were only set up to take left-hand turns and had 0 oiling provisions back then to handle heavy braking...
So yeah, it seems they really do work based on first hand-testimony I've heard and the fact that Lotus uses them on their cars.
I do still think the pump idea is pretty ingenious. It's a ghetto dry-sump system and it serves BMW well on their Motorsports applications. I am still tempted to do it but I've honestly spent so much time working on the car that it's going to have to wait for now. It does still kind of bother me that aerated oil is making it through the oil pump... Accusump feels like it's just masking that pressure loss. Not exactly sure about the fluid dynamics/science behind how it all works at that point lol but apparently it saves bearings.
https://www.optimabatteries.com/en-us/experience/2013/08/ousci-invitee-ken-edwards-1966-ford-mustang
This car screams. It sounds as brollock as it looks.
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Man, I really need to find time to mount my accumulator. I can't decide where I want to mount it. I'm thinking under the rear parcel shelf. My rear interior is gutted. I was also thinking about removing the storage bin in the trunk and using the Hard motorsport sheet to close the hole and mounting it on the underside of that above the muffler. But that seems less than ideal for a number of reasons.
The mustang above runs a 3qt in the trunk. He acknowledge that isn't the best place for it. They both advised to keep the lines as short and large as possible (8AN+). Luckily mine fits right over the intake manifold on my N55 as seen back in the original post. I think you said you're N54 though and it wouldn't work there. It does take up a lot of space. Trunk might be the best bet. Or, find a way to tuck it into the engine bay somehow.
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screaminfast
Sergeant
I'm thinking I might have room for it on the drivers side where the coolant res was since I have relocated inlets.
I've definitely hit an issue with gravity-induced oil starvation. Had some r-comps on and took a corner on the street decently fast + high rpm and it threw my engine into limp mode. Took ~15secs to re-crank it, no issues after and it never returned so there's definite proof of all this in my book even for those of us who don't track the cars. Sigh, another thing to add to the wishlist.
are you sure that wasn't fuel starvation? Have a bucketless pump?
We installed an oil pressure gauge Tuesday and today I managed to do some video logging of the gauge to see how well the semi-dry oil sump system works on my car. In conclusion it can be rated for 1.0Gs but not for over 1.3Gs. Where the exact line is I am not sure of, but the problem is only there on left turns.
Basic data
Normal acceleration: 100-120psi
Idle: 40psi depending on temperature
Driving in circles:
Driving on track running Pirelli DM slicks
No problems during right turns. Saw as low as 50psi going through left turns when pulling high Gs.
Example from one lap (not the worst in terms of oil pressure, but the fastest of the test)
Manually filled datalog from that lap. I just put in 100psi whenever the gauge showed above 100psi.
The gauge has some delay, so it is unknown if the peak values are worse than what I am able to report from the video log.
Let me know your thoughts. Do I need to stop running slicks? The M4 GT4 uses a standard S55 engine in combination with slicks I believe.
Basic data
Normal acceleration: 100-120psi
Idle: 40psi depending on temperature
Driving in circles:
| Avg speed: 100km/h | 60mph | Oil pressure turning left | Oil pressure turning right |
| AD08r tires avg 1G Semi-dry oil sump turned off | +80psi | +100psi |
| AD08r tires avg 1G Semi-dry oil sump turned on | +100psi | +100psi |
| Pirelli DM slicks more than 1.3Gs Semi-dry oil sump turned on | Stopped when pressure dropped below 80psi which took less than one circle | +100psi |
Driving on track running Pirelli DM slicks
No problems during right turns. Saw as low as 50psi going through left turns when pulling high Gs.
Example from one lap (not the worst in terms of oil pressure, but the fastest of the test)
Manually filled datalog from that lap. I just put in 100psi whenever the gauge showed above 100psi.
The gauge has some delay, so it is unknown if the peak values are worse than what I am able to report from the video log.
Let me know your thoughts. Do I need to stop running slicks? The M4 GT4 uses a standard S55 engine in combination with slicks I believe.
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We installed an oil pressure gauge Tuesday and today I managed to do some video logging of the gauge to see how well the semi-dry oil sump system works on my car. In conclusion it can be rated for 1.0Gs but not for over 1.3Gs. Where the exact line is I am not sure of, but the problem is only there on left turns.
Basic data
Normal acceleration: 100-120psi
Idle: 40psi depending on temperature
Driving in circles:
Avg speed: 100km/h | 60mph Oil pressure turning left Oil pressure turning right AD08r tires
avg 1G
Semi-dry oil sump turned off+80psi +100psi AD08r tires
avg 1G
Semi-dry oil sump turned on+100psi +100psi Pirelli DM slicks
more than 1.3Gs
Semi-dry oil sump turned onStopped when pressure dropped below 80psi which took less than one circle +100psi
Driving on track running Pirelli DM slicks
No problems during right turns. Saw as low as 50psi going through left turns when pulling high Gs.
Example from one lap (not the worst in terms of oil pressure, but the fastest of the test)
Manually filled datalog from that lap. I just put in 100psi whenever the gauge showed above 100psi.
The gauge has some delay, so it is unknown if the peak values are worse than what I am able to report from the video log.
Let me know your thoughts. Do I need to stop running slicks? The M4 GT4 uses a standard S55 engine in combination with slicks I believe.
Can't speak to it all that much since i don't have an n54 to log and compare to. The n55 has a map controlled bypass valve to reduce oil pressure at low rpms and load so it's normal to see ~60psi+ at >3,000 rpms, 80psi at full load/rpm, and 40psi at idle... I would imagine the N54 would sit a little higher at all rpms. When the N55 is in "emergency mode" I sit at close to 48psi at idle and 100psi or so at full load. That sounds pretty similar to what you're showing. Makes sense since both cars run the same style sliding vane oil pump.
I see the oil pressure dips occur as you start dipping below 3,000rpm so it might just be normal but then that doesn't agree with you finding it to only occur on left hand turns. I am pretty surprised to see the N54 is running 100psi+ at pretty much all times that seems excessive lol.
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We installed an oil pressure gauge Tuesday and today I managed to do some video logging of the gauge to see how well the semi-dry oil sump system works on my car. In conclusion it can be rated for 1.0Gs but not for over 1.3Gs. Where the exact line is I am not sure of, but the problem is only there on left turns.
Basic data
Normal acceleration: 100-120psi
Idle: 40psi depending on temperature
Driving in circles:
Avg speed: 100km/h | 60mph Oil pressure turning left Oil pressure turning right AD08r tires
avg 1G
Semi-dry oil sump turned off+80psi +100psi AD08r tires
avg 1G
Semi-dry oil sump turned on+100psi +100psi Pirelli DM slicks
more than 1.3Gs
Semi-dry oil sump turned onStopped when pressure dropped below 80psi which took less than one circle +100psi
Driving on track running Pirelli DM slicks
No problems during right turns. Saw as low as 50psi going through left turns when pulling high Gs.
Example from one lap (not the worst in terms of oil pressure, but the fastest of the test)
Manually filled datalog from that lap. I just put in 100psi whenever the gauge showed above 100psi.
The gauge has some delay, so it is unknown if the peak values are worse than what I am able to report from the video log.
Let me know your thoughts. Do I need to stop running slicks? The M4 GT4 uses a standard S55 engine in combination with slicks I believe.
@Asbjorn good info. Love the data driven approach.
@sirdaft1 maybe something to discuss with E-Fab regarding your build? You're running some pretty meaty tires.
I saw several dips happening at around 4000rpm as well. I would say it is definitely lateral G force related, as well as directional with my setup.
I also double checked the pressure at high rpm. It does indeed stay above 100psi at 6500rpm.
That's not to say the gauge can't be inaccurate though. Unfortunately my AiM device only supports DME logging.
This looks like a great solution. Several questions:
1. Does the banjo bolt touch the hood?
2. Can you be more specific on how you secured the Accusump in that spot?
3. What is the parts list...looks like:
- Mishimoto 90 deg banjo
- X feet of AN10
-one 90 deg AN10 fitting
What brand do you recommend?
TIA!
1. No. This banjo bolt is perfect for that exact reason. Hood clearance.
2. I strapped it to the chargepipe lol It's pretty janky setup but it works. I zip tied it to the front bump support too.
3. Yep, pretty basic. I think I used 3 or 4 feet of AN line. I also ran some small gauge wire to a switch and light in the cabin. this allows me to see when the accusump discharges via the light. The switch allows me to active/deactivate the accusump at any time. So, sitting in the pits I keep it switched off since oil pressure is below the 55psi set point. I can also use it to prime the engine prior to cranking.
Brand? Accusump and Moroso are the only two I know of. I am partial toward the Canton product because I have one. Feel free to call them and discuss. They will be happy to exchange information and experience with customers.
Thx! Sorry for not being clear, for brand I was referring to AN hose, since the cheap stuff you bought broke.
