RPM EXCLUSIVES
ACCUMULATOR MAGIC
>>Kill a little windage and protect your motor from dry starts and momentary oil starvation with a simple oil accumulator
Y
ears ago a local 10.5 Outlaw racer clued me into the advantages of an oil accumulator. I had never even heard of one at the time but it didn’t take me long to find a used one for my car. I had good success with it and saw firsthand the advantages. When you get on the brakes hard or pull the chute at the end of a run, your oil rushes to the front of the pan, momentarily uncovering the oil pump pickup. This will cause the engine to lose oil supply until the oil falls back down to the sump when the car’s deceleration slows. A good oil pan like the Jeff ohnson pan on Project 4-Lug helps prevent or lessen the severity of this flaw to a wet sump oiling system, but an accumulator can be your best line of defense.
An oil accumulator is just a pressurized reservoir that can hold extra oil and give it to your motor if oil pressure drops lower than the air pressure in the other end of the accumulator. It is basically a cylinder with a piston that separates the side pressurized with air and the side that is pressurized by your oil pump. You charge the air side with standard shop air by the common air valve like used on tires. The oil from your engine gets pumped into the accumulator by the running engine and overcomes the lower pressure of the air side. The air is compressed until it raises to the equivalent of your engine oil pressure. You can adjust the amount of oil the accumulator will hold by how much initial air charge you give the accumulator. Less air pressure will allow
more oil into the cylinder but the tradeoff is the oil moves back to your motor slower if ever the engine oil pressure drops. More initial air pressure will get you a faster blast of reserve oil when you lose momentary oil pressure, but the accumulator holds less oil in reserve. Oil is fed to the accumulator by tapping a pressure source of the engine. This can be done by adding an adapter between the block and oil filter or teeing a feed line to an oil cooler or filter relocation kit. The Dart block in the project car has a priority oil port on the back of the block that is the ideal place to connect the accumulator line. Not only does it provide a nice place to feed oil to the accumulator, when the accumulator feeds back to the engine, the oil goes to the most-needed areas
by
Chuck Scott
1 1: We picked up a new 3-quart accumulator from CVR with a set of optional 1.5-inch round tube bracket clamps. The CVR is the best made accumulator I have found with its billet end caps and integrated brackets. It is sturdy enough for any pressure your engine can give it. Plus it looks awesome.
cvrproducts.com For more information visit
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may 2016 | RPM Magazine
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www.cvrproducts.com