1gary

In my case a N/A OEM BBC wet sump.Anyone use one and what are you using for the entry back into the block??.

AlkyIROC

I use a Moroso accumulator.

Remote mounted filter with anti drainback. Accumulator is teed into outlet of remote filter.

On the older Dart big M blocks, they had a large port plug beside the filter boss. A single line from that port to the accumulator worked perfectly. With the new Dart Big M, if you want that port, you need to drill and tap it out yourself. I didn't bother and just went off the remote filter.

Any large gallery port such as a 1/2" or 3/4" pipe plug preferably beside the filter housing is good enough to run an accumulator.

Minimal air pressure behind the piston in the accumulator. When the engine is fired up, oil pressure fills the accumulator pushing against the piston. If oil pressure drops below the minimal air pressure, the air pressure will push the oil back into the galleries until the pump can pick up oil to make pressure again which will fill the accumulator.

If there's enough oil in the sump, the oil in the accumulator will change very little. If you're drag racing and at the top end of the track, there may be very little oil left in the sump and the accumulator will keep the bearings fed until oil gets back into the sump.

In road course or oval racing, oil is constantly being pushed to other parts of the pan and the accumulator will help keep a more stable oil pressure.

If you don't have an oil pressure issues for the type of driving you do, you don't really need an accumulator but it's good insurance to protect the engine if something unexpected happens.

1gary

Are you also using a low/no oil pressure sensor??.If so,which one??.

AlkyIROC

I use a 25 psi sensor to turn on a warning light. I only run 15 psi air pressure in the accumulator. The warning light will come on before pressure gets low enough that the accumulator starts working. Hopefully the warning light will catch my attention to look at the pressure gauge to decide if the engine needs to be shut down or not.

I've seen the light come on in the shutdown area as oil in the pan moves forward. Pressure never dropped to zero. Just low enough to turn on the light before the accumulator pushes oil back into the galleries.

Oil moves freely in and out of the accumulator. There's a manual ball valve on it but I normally keep it open all the time. I use an electric shutoff valve to trap oil in the accumulator when the engine is off. Makes checking the oil level in the engine much easier. As soon as the ignition is turned on, the valve opens and the engine gets a bit of a prelube before it starts. When the engine starts, the accumulator fills back up.

572_Rat

I have been looking into the accumulator, I have 2 question for you, the instructions says to have unit set at 6psi you have yours at 16, can you tell me why the difference, also you have the electric solenoid, do you have the one with the set pressure switch, or just on or off, if so why. Thanks

AlkyIROC

It works on pressure differential. High pressure will always push the piston towards low pressure.

If the accumulator pressure is set to 6 psi then it won't start pushing oil into the galleries until gallery pressure is less than that. With a high HP, high rpm engine if my pressure dropped to 5 psi while at 7000 rpm, it would already be too low.

Setting the accumulator pressure higher it will maintain oil to the galleries and bearings long before any damage can be done. With a higher pressure warning light, I will see the warning light come on before the accumulator starts working. If I see any serious issue on the pressure gauge, I can shut the engine down and let the accumulator fill the galleries until the engine rpm comes down to zero.

As nice as having a pressure gauge is, you don't have time to watch it during a run. I'll let the oil warning light give advance warning that something may be wrong. Hopefully the accumulator won't even be used but it's there just in case.

I've had the accumulator pressure set lower before. Slowing down hard at the top end, I would see the warning light come on. Pressure had dropped to 10 PSI but the accumulator was set to 5 PSI. Easing off on the brakes allowed oil to drain to the back of the sump and the pump started picking up oil again which filled the galleries and brought pressure back up.

Setting the accumulator pressure higher means gallery pressure never gets that low unless there's a major failure with the oiling system or the engine has stopped.

I've been tempted to install an oil pressure cutout switch. If oil pressure hits 3-5 PSI, switch contacts open and ignition is disconnected killing the engine. Just another safety feature to protect your investment.

The electric solenoid is powered from my main power switch. It prevents the oil from draining into the engine when the engine is off. Makes it easy to check the oil level on the dipstick. You can also use it as a prelube. Turn on power, the solenoid opens and oil galleries start to fill. You can watch the pressure gauge start to climb. Turn on ignition and start cranking over the engine. When it starts, accumulator gets refilled. If I kill the engine with the ignition switch, the solenoid stays open and oil fills the galleries. If I kill the engine with the main power switch, the solenoid closes trapping the oil in the accumulator. Both switches are beside each other and when I normally shut the engine down, I hit them both at the same time or one right after the other. If I kill it with the main power, it also kill my data logger so I need to make sure it's done saving the data first or the data gets lost. Driving around the pits, in or out of my trailer or garage, I'm not logging data. Any emergency kill while going down the track has to be ignition switch only. That way data is still being logged and accumulator still feeds the engine until it's empty.

Twin_Turbo

iTrader: (25)

You are confusing the pressure differential over the piston with the initial setting. If you set it @ 6psi, it takes 6psi of oil pressure to start moving the piston to the closed end of the accumulator, moving oil volume into the accumulator. At a steady pressure of say 50psi there is 50psi on boith sides of the piston. One side engine oil pressure, the other side initial air pressure + whatever it took to attain an equillibrium over the piston. Now, if your oil pressure drops in the engine pressure drops, volume is moved out of the accumulator into the gallieries until pressure equalizes over the piston. If engine pressure rises, the piston moves, more volume is entered into the accumulator and air pressure on the other side builds to equal oil pressure. This is a constant (dynamic) process. However, it means that it does not take until the initial set pressure to move any oil What it does mean is, it takes an oil pressure BELOW the initial setting to move ALL the oil out of the accumulator.

572_Rat

From what I am understanding, as soon as engine oil pressure drops the accumulator will start pushing oil out. Moroso has electronic solenoids, they have two types, one with pressure switch and the other without. Is there one that has and advantage over the other

AlkyIROC

OK, think of it this way then. My warning light comes on at 25 psi. Accumulator is empty at 15 psi. If there's still an oiling issue, I should be able to get the engine shut off before pressure hits zero or very shorty after.

All the racing I've done with the accumulator set up like this, I have not seen the oil warning light come on during normal runs. If my pressure drops below 25 psi, I have issues. The light did come on during my second sky high wheelie. When the car came back down, the pump drive disengaged from the distributor. An adjustable collar distributor has fixed that problem. The only damage done was some scuffed bearings. I was too concerned with the rest of the car to notice the oil light. I got an awesome high intensity strobe mounted in the dash for an oil warning light now. Can't miss it flashing. That's also why I'm considering an oil pressure switch for the ignition.

572_Rat

Thanks for all your help, I bought the Moroso unit, talked to both Canton and Moroso and feel the Moroso unit is better especially after talking to a tech at Moroso that worked at canton