Accusump oil level?

[ZDan]

Successfully installed Accusump, thanks Ansix Auto!

I may have overfilled though, I'm seeing +1/4 quart overfill at 100psi and +1.25 qt overfilled at 20psi! OK to track or not? Kind of assuming that any overfill will be dealt with by PVC but let me know if I need to take oil out before tracking at Mosport in a few days.

Thanks!

[blsfrs]

Have you looked up Boyles Law yet? I found it helpful to calculate the amount of oil in the accumulator at a given pressure.

I'm not a fan of the electronic switches. When deactivated, they still allow oil flow into the accumulator. On a cold start with 100+ psi you push a lot of oil into the accumulator. Also, they are slow to react to a drop in OP. From what I have seen, the drop in OP is momentary. By the time the switch would activate, the pressure is already coming back up.

I use a manual valve with a PTO cable. When the engine is warm, I open the valve, hold rpms so the OP is around 70 psi and then close the valve. I then top off the oil in the engine.

[ZDan]

Originally Posted by blsfrs

Have you looked up Boyles Law yet? I found it helpful to calculate the amount of oil in the accumulator at a given pressure.

Linear relationship, so lower initial charge pressure = greater oil volume into Accusump.

I'm not a fan of the electronic switches. When deactivated, they still allow oil flow into the accumulator. On a cold start with 100+ psi you push a lot of oil into the accumulator. Also, they are slow to react to a drop in OP. From what I have seen, the drop in OP is momentary. By the time the switch would activate, the pressure is already coming back up.

I have the electric valve but not using a pressure switch, I just have an on/off switch in the cockpit. On the street, I open the valve to pre-oil before starting and leave it open until the oil warms up, the close it at ~4000-5000rpm to have a decent pre-charge for next startup. At the track I will leave the valve open for a stint, then close it on the cool-down lap or in the pits, again at ~5000rpm for pre-oiling.

I use a manual valve with a PTO cable. When the engine is warm, I open the valve, hold rpms so the OP is around 70 psi and then close the valve. I then top off the oil in the engine.

OK, we are doing the same thing. I intended to have it a little bit over-filled at 60ish psi but I unintentionally overfilled a bit more then I meant to...

[autoracer86]

Originally Posted by ZDan

I have the electric valve but not using a pressure switch, I just have an on/off switch in the cockpit. On the street, I open the valve to pre-oil before starting and leave it open until the oil warms up, the close it at ~4000-5000rpm to have a decent pre-charge for next startup. At the track I will leave the valve open for a stint, then close it on the cool-down lap or in the pits, again at ~5000rpm for pre-oiling.

What sort of changes are you seeing to oil pressure when doing this ? Does the accusump eliminate oil pressure loss in corners or just helps for quicker recovery.

Thanks

[ZDan]

Originally Posted by autoracer86

What sort of changes are you seeing to oil pressure when doing this ? Does the accusump eliminate oil pressure loss in corners or just helps for quicker recovery.

Thanks

Only just installed it, and stupidly enough I have no way of measuring pressure (should have installed pressure sensor in the electric valve...).
First track days with it Monday/Tuesday.

I am 100% relying on the testing of others on this. Ansix Auto (great deal on the whole kit btw), 900BRZ, BTR Justin, etc. There's lot's of great test info out there.

From everything I can tell, the Accusump greatly reduces pressure drops and recovers from them sooner.

From Ansix:

[blsfrs]

Correct me if I am wrong, (my wife does it all the time) but the electronic valves allow the accumulator to fill with oil even when "off".. Yes? It makes it harder to get to correct oil level in the engine.

Years ago, I graphed pressure vs volume. It seems to follow a slope not a straight line.

[ZDan]

Originally Posted by blsfrs

Correct me if I am wrong, (my wife does it all the time) but the electronic valves allow the accumulator to fill with oil even when "off".. Yes? It makes it harder to get to correct oil level in the engine.

Years ago, I graphed pressure vs volume. It seems to follow a slope not a straight line.

Should be a linear slope, no?

Yeah I have a hard time reading oil levels anyway, one side of dipstick says full, other side says 1/2-qt overfilled…

[blsfrs]

Sorry, my last trig class was many moons ago so my grasp of terminology is foggy at best. If you plot the volume v pressure the line is curved not straight. Parabolic might be what I'm trying to describe.

[ZDan]

Originally Posted by blsfrs

Sorry, my last trig class was many moons ago so my grasp of terminology is foggy at best. If you plot the volume v pressure the line is curved not straight. Parabolic might be what I'm trying to describe.

P1V1 *should* = P2V2. I doubt the dipstick scale is linear...

[smackrel]

Originally Posted by ZDan

Should be a linear slope, no?

Yeah I have a hard time reading oil levels anyway, one side of dipstick says full, other side says 1/2-qt overfilled…

Right?!?

Is there a consensus on this? Average out the 2 sides? Always go by the lower? The higher? Keep adding till it comes out the breather?

[blsfrs]

Originally Posted by smackrel

Right?!?

Is there a consensus on this? Average out the 2 sides? Always go by the lower? The higher? Keep adding till it comes out the breather?

Never check you oil when there's a full moon. The tidal forces pull the oil to one side of the pan.

[smackrel]

Makes sense. Ill make sure to check my Lunar calendar before I schedule a oil check next time.

[GrandSport]

Originally Posted by ZDan

Successfully installed Accusump, thanks Ansix Auto!

I may have overfilled though, I'm seeing +1/4 quart overfill at 100psi and +1.25 qt overfilled at 20psi! OK to track or not? Kind of assuming that any overfill will be dealt with by PVC but let me know if I need to take oil out before tracking at Mosport in a few days.

Thanks!

What PSI does it open at?

Of course it's going to be high at low pressures- the accusump is pumping in oil!

Prior to accusump we ran with about a quart over full and it was fine.

[ZDan]

Originally Posted by GrandSport

What PSI does it open at?
Of course it's going to be high at low pressures- the accusump is pumping in oil!
Prior to accusump we ran with about a quart over full and it was fine.

I am running it on track with the electronic valve open all the time. For "normal" usage, I'll open the valve before startup, then close it after it has warmed up a bit.