Questions about accusump/ accumulators
 

I just got my 2019 BRZ back from my mechanic with a brand new engine. The previous engine exploded at the track (threw a rod, basically grenaded my engine). Probable cause was oil starvation despite using 5W40, an oil cooler, and a 0.5 quart overfill.

I track my car regularly, use 200 TW tires, and run in the advanced/ instructor groups. I am concerned about my new engine, as my home tracks (NJMP) have some big right sweepers.

I am considering installing a 2 Quart accusump (larger because we have some looooong right corners). It looks pretty straightforward, but I have a few questions. I will probably use an electronic switch which should allow the accusump to fill even when it is off.

If I have the switch on while the engine is idling, the oil pressure during idle is pretty low (10-15 PSI?) so the accusump would fill the engine with oil until the pressure in the accusump is equal to the idle pressure, and would result in most of the oil going into the pan. If I have the engine slightly overfilled before the accusump empties, then this would create an even greater overfill, probably with some foaming, and other bad results.

Pressure-triggered switches would probably be just as bad, as they would also open and dump oil into the gallery when the engine is idling.

Should I keep the switch off most of the time and then only open it when the car is moving and the RPMs are above idle (and oil pressure is higher)? Then make sure to switch it off before letting the engine slow to idle?

How can I keep from seriously overfilling the pan with oil when the engine is at idle and the switch is open? A manual switch would be worse, as I would have to turn it on while the engine is idling, then get into the car and drive.

Suggestions? Thoughts? Do I have an appropriate understanding of how things work??

Thanks.

Glenn

You're right on pretty much all regards.

You'd want an electronic switch to activate the Accusump when the car is moving and above discharge pressures (IE Out Lap). and deactivate while on cool down (IE Cool Down Lap)

https://www.ft86club.com/forums/showthread.php?t=153935
https://www.ft86club.com/forums/show....php?p=3570279
These are just a couple of links. A little more googling will yield more answers

I wouldn't worry about the overfill while the engine is running. there's enough gap in the bottom of the engine that you can fill it with all 6-7-8qts necessary and then start the car and fill the accusump without sloshing against the bottom of the crank.

also, the accusump electric valve works as a 1-way valve when you have it powered off. the tank will fill when powered off as the oil pressure builds.

I simply have a switch on the dash for mine and I turn it on during my out lap. I often forget to turn it off post-race, so will cruise around the pits at idle with it on and no problems with excess oil in the engine.

Eventually, I plan to hook that switch to a relay on my AIM dash so it only runs when I'm logging data, but I've been too lazy to do that work. (the AIM is configured so it automatically starts logging when the engine is above 2500RPM and a couple other variables. but essentially any time I'm moving fast enough to need the accusump, the logger is running. therefore it's an easy trigger.

Thanks.
Planning to install this way. but try to remember to turn it off as I come in to the paddock

This guy is doing some nice Accusump testing on his Gen 2.

https://www.ft86club.com/forums/show...=153798&page=3