Cooley On Cars
Car Tech 101: Inside dry-sump systemsBrian Cooley explains the nuts and bolts of dry-sump lubrication systems and how they benefit high-performance engines.
[MUSIC] Now most cars, including very likely yours, have what's called a wet sump. Sump being the old German That's a word for a muddy, wet bog or marsh. Which is actually a pretty good analogy for what happens down here, at the bottom of your engine. It's what's know as the oil pan or crank case, also known as the sump. The heart of the lubrication system is the oil pump. The two revolving gears create a As the teeth move apart, this suction draws oil from the storage reservoir or oil pan. [MUSIC] When this is a wet sump that means basically all your oil lives down here except when it's being pumped out, circulated around the engine through little passages where it gets all the things that need lubrication lubricated And then it drips back down here to do the cycle all over again. [SOUND] The problem with that design are probably many. First of all, look at this pan down here or on this V8 to my right, they're both big and tall. That means the engine has to sit higher in the car. To not scrape the ground, or bump into suspension, that means a higher center of gravity, a higher hood nose what have you, the auto makers don't like that. Secondly the oil keeps coming back to the same hot place, so it's hard to cool the oil Third, because this can only be a given size to fit in an engine bay, you can only have so much oil, and engines would like to have more oil, fresher oil, and cooler oil. And fourth, you get oil starvation in a design like this. The oil is just kind of down there by luck and by gravity, and [UNKNOWN] sometimes it moves to one side And the pick-up where the oil is sucked up goes dry once in a while. When that happens, the bearings go dry. Not good for high performance engines. A dry stump seeks to cure all that. [NOISE] The first high performance sports car with dry sump lubrication for a lower center of gravity. [MUSIC] A dry sump engine still has a pan at the bottom of the engine but it's much smaller. It catches oil and it's immediately then pumped out to a reservoir somewhere else on the car where typically another pump then moves it back to the engine. It's all very controlled and done under positive pressure You end up getting a lower engine and lower center of gravity because you don't have a great big pan to to protect down at the bottom. You have no oil starvation and hard cornering cuz everything is done under positive pressure. And you end up likely with cooler oil because it gets a vacation from being in the engine all the time. And you can have a lot more of it, because the oil reservoir can be as big as you have room to fit. The downside of a dry sump design is basically cost and complexity. You've got a pump or two that are external to the engine, you've got some very critical plumbing, and you've got that reservoir to hold all that oil, has to go somewhere else in the car, so they're only justified in high performance situations today. But if you look at a high performance car, look at our reviews of them You're going to increasingly see the dry sump design making its way into vehicles that are not just track cars. That are high performance road cars. [MUSIC] More car tech, demystified, right now at CNETOnCars.com. Click on CAR TECH 101. [MUSIC] [BLANK_AUDIO]