[This message has been edited by lou_dias (edited 09-19-2022).]

I've been considering adding an accumulator to my oil system as well. I'd rather it be mounted to the powertrain and/or cradle as opposed to in the driver compartment so that in the event of a failure of the accumulator, or the lines, I don't have potentially hot oil spraying inside of the car. simple cloth spray guards made of shop rags and zip ties can go a very long way to limiting the ability of the oil to travel, and spray in the event of such a failure, and have almost no weight penalty. I would also recommend a hose restraint of some kind to ensure that in the event of a hose end failure, the hose cannot "whip" in the driver's compartment.

quote Originally posted by Patrick: Interesting. I take it then that the extra 1-1/2 quarts of oil that are "injected" into the engine's oil system (when the accumulator temporarily empties) at startup isn't an issue at all?

I'm not sure I would add the entire working volume of the accumulator to the oil pan, it's been dyno proven that oil aeration removes power from an engine, and frequently, a somewhat lower oil fill, will actually produce more power than a standard fill, even on engines with solid camshafts. obviously you need to be careful about how much oil you have in the pan, too little and the pump cavitates, or you suck the pan dry too much and the rotating and reciprocating components aerate it. My thought would be to add an additional pressure gauge, and if not already done, a check from the oil pump, to the accumulator.



here we have the oil pump, the pickup in the pan, a check valve, and the accumulator, obviously an engine will have a filter and maybe a cooler, but you get the idea. by instrumenting oil pressure both post pump(red circle), and post accumulator(blue circle), excessive aeration, or cavitation of the pump can be seen by a loss of pump discharge pressure, the accumulator however, should maintain oil pressure to the lubricated components of the engine. now that we have data, we can carefully adjust oil fill such that aeration is minimized, yet cavitation also does not occur. When I get around to adding an accumulator, I will start by using a oil fill level slightly above stock fill, but probably less than stock fill+ working volume of the accumulator, then monitor datalogs for indication of lowering pump discharge pressure and add/remove oil to determine the optimum fill

Obviously a dry sump would be ideal, but a vacuum pump should also help minimize oil aeration, because the oil can't mix with the air if it isn't there. this should increase the oil return rate to the pan as well. but I would probably develop my optimum fill around no vacuum, so that if a loss of vacuum is experienced, oil control is still somewhat maintained.

it's also worth mentioning that monitoring the air side of the accumulator is critical, if it loses pressure, it will fill completely, and not discharge. at a minimum, it would be very wise to check the pressure before every race event, and maybe even on each pit at least until a baseline for leak down is established. installing a low pressure warning light switch might not be a bad idea.

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"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

I invited Lou Dias to trash me in my own thread, he refused. sorry. if he trashes your thread going after me. I tried.

No pushrod 60V6 Fiero has been faster according to the 1/4 mile list.

[This message has been edited by ericjon262 (edited 10-12-2022).]