| Re: To dry sump or not to dry sump that is the question |
Subject: Re: To dry sump or not to dry sump that is the question by rklessdriver on 2011/10/25 23:19:59 I'd like to add some more basic tech info for those that don't know what we are talking about. There are lots of benefits to dry sumps and the only real draw back is the cost. Dry sumps are a more efficient oiling system because they have at least a 2 stage pump (pressure and scavenge). Some pumps are multi stage with lots of scavenges. We run between a 4-6 stage pump depending on type of engine and application. The scavenge stage(s) pump oil out of the engine and into a holding tank. This action keeps the pan practically dry so there is far less windage in the crank case for the rotating assy to contend with. When you step up to multi stage pumps you can compartmentalize your oiling system. You can scavange oil from the cyl heads, the lifter valley and the crank case all seperatly. First not only does this make more HP, secondly it makes the engine more reliable and third easier to repair in the event of a failure. Some of these pumps are so efficient that we can even use a dedicated stage off the pump to pull a vacuum in the crank case which free's up a little more HP. Oil is a liquid and it's heavy. Most endurance race cars can run a couple gallons of oil. With a dry sump you can place the oil holding tank where it will best benefit the weight distribution of the car. On most modern dry sump systems the pump runs off the crankshaft via a belt drive. This alone has alot of advantages over the cam driven wet sump a stock engine has. Belts are very efficient and have very little frictional loss. No gear to gear contact which means less heat and metal in the oil. Less torsional stress on the camshaft, which lessens some valve train harmonics. Lasty on an engine like the SBC/BBC/BBF/SBF which uses the distributor as an intermediate drive for the oil pump - the oil pump load can effect the ignition timing... no more with a belt driven dry sump system. Hope that helps those that need info out. Will |
