Domesticated
05-26-2009, 02:13 AM
The biggest thing to be careful when using a proper built and tuned turbo system is the cooling and lubrication of the turbo itself. Turbos go bad because of choking. Choking is when there is such a buildup of burnt oil residue that the bearing will wear out causing “shaft play” and eventually lock up or break. Things that cause choking is the oil being unable to operate at the turbo temperature, oil with a too wide multi viscosity range, i.e. 10w-50, 10w-40, too high of shaft temperature, and not changing oil often enough. A good turbo oil will have a lower range like 10w-30 or even 5w-20, as long as your operating temp is pretty constant. You wouldn’t want such a small range if you car starts at 10 degrees in the winter and the oil gets up to 400 degrees in the turbo. A proper warm up can help that situation though. Reason you want a small range viscosity is because the additives that oil makers put in the oil to widen the range, are the same chemicals that break down, burn out, and cause choking. Also oil that has a high ant oxidizing rating and a high detergent rating makes for a good turbo oil.
Since this is my write up I will give my opinion, Schaffer 9000 full synthetic is the best oil out there, I’ve researched torture test on all the popular oils and it outperformed Royal Purple and it’s a couple bucks cheaper. When I switched from RP to Schaffer 9000 my engine temp dropped about 15 degrees and my power band went up 300 RPM. Its also green and looks really cool.
Water cooled turbos has pretty much ended the problem of choking, it allows the turbo to be cool enough to prevent the oil from breaking down, but all oils break down over time so choking can occur with improper oil changes. Depending on the oil choking usually occurs at around 300 degrees. Oil cooled turbos can reach up to 400 degrees at the exhaust end and about 200 degrees at the intake side. So obviously choking can occur. Now a water cooled turbo will generally be just under 300 degrees at the exhaust side and as low as 100 degrees on the intake side depending on the car and cooling system. It is especially important to keep ball bearing turbos oiled and cooled properly because, though they have better performance, they can break down easier. Oil coolers are thought to be required, but that’s not always true. Oil operates best at the temperature its designed to operate at, therefore oil that’s too cool will not lubricate properly. Its best to look at your oils recommended operating range and cool if necessary. Now those of you with money and want a truly well designed system will install a thermostat system where when the oil reaches a certain temperature, it diverts the oil to a cooler, keeping the oil at proper temperature all the time.
Oil pressure is also important. Most engines have enough extra oil pressure and flow to account for a turbo because turbos don’t actually need that much flow. Every turbo is different, but it’s a rule of thumb that oil pressure from 60-80psi will actually push oil past the seals in a turbo. This cause smoking and eventual failure. Find out what pressure maximums your turbo operates at make sure the pressure doesn’t exceed it. Now an oil pressure gauge in your motor will not read the correct oil pressure at the turbo. The line to the turbo and the path through the turbo may be larger or smaller than that by your oil sensor, which in turn increases or decrees pressure. If pressure at the turbo is too high, us a restrictor in the oil line.
Designing the turbo lube system is very important, and when done right looks awesome. I would use only steel braided lines and make sure to anchor them when possible because the steel lines can wear through even aluminum. Most turbos can be “clocked”, meaning the compressor housing can be rotated on the exhaust housing, and the oil line should be straight up and down because the oil pressure is lost at the shaft bearing and only gravity drains the oil. A steel braided line should be used and a proper fitting should be installed on the oil pan.
That concludes all I can think of when lubricating a turbo motor, one thing that I would highly recommend and almost require is a turbo timer. It keeps the motor running for a set amount of time after the car is turned off to allow the turbo to get a nice fresh and cool supply of oil before its stops turning.
Since this is my write up I will give my opinion, Schaffer 9000 full synthetic is the best oil out there, I’ve researched torture test on all the popular oils and it outperformed Royal Purple and it’s a couple bucks cheaper. When I switched from RP to Schaffer 9000 my engine temp dropped about 15 degrees and my power band went up 300 RPM. Its also green and looks really cool.
Water cooled turbos has pretty much ended the problem of choking, it allows the turbo to be cool enough to prevent the oil from breaking down, but all oils break down over time so choking can occur with improper oil changes. Depending on the oil choking usually occurs at around 300 degrees. Oil cooled turbos can reach up to 400 degrees at the exhaust end and about 200 degrees at the intake side. So obviously choking can occur. Now a water cooled turbo will generally be just under 300 degrees at the exhaust side and as low as 100 degrees on the intake side depending on the car and cooling system. It is especially important to keep ball bearing turbos oiled and cooled properly because, though they have better performance, they can break down easier. Oil coolers are thought to be required, but that’s not always true. Oil operates best at the temperature its designed to operate at, therefore oil that’s too cool will not lubricate properly. Its best to look at your oils recommended operating range and cool if necessary. Now those of you with money and want a truly well designed system will install a thermostat system where when the oil reaches a certain temperature, it diverts the oil to a cooler, keeping the oil at proper temperature all the time.
Oil pressure is also important. Most engines have enough extra oil pressure and flow to account for a turbo because turbos don’t actually need that much flow. Every turbo is different, but it’s a rule of thumb that oil pressure from 60-80psi will actually push oil past the seals in a turbo. This cause smoking and eventual failure. Find out what pressure maximums your turbo operates at make sure the pressure doesn’t exceed it. Now an oil pressure gauge in your motor will not read the correct oil pressure at the turbo. The line to the turbo and the path through the turbo may be larger or smaller than that by your oil sensor, which in turn increases or decrees pressure. If pressure at the turbo is too high, us a restrictor in the oil line.
Designing the turbo lube system is very important, and when done right looks awesome. I would use only steel braided lines and make sure to anchor them when possible because the steel lines can wear through even aluminum. Most turbos can be “clocked”, meaning the compressor housing can be rotated on the exhaust housing, and the oil line should be straight up and down because the oil pressure is lost at the shaft bearing and only gravity drains the oil. A steel braided line should be used and a proper fitting should be installed on the oil pan.
That concludes all I can think of when lubricating a turbo motor, one thing that I would highly recommend and almost require is a turbo timer. It keeps the motor running for a set amount of time after the car is turned off to allow the turbo to get a nice fresh and cool supply of oil before its stops turning.