CK_32

iTrader: (1)

Ok so I understand the process and need for oil circulation from the pan into the turbo and I slightly understand water cooling (honestly haven't taken the time to look at it in depth yet)




But my question is, oil temps and turbo cooling is a semi big issue with turbos. Mostly due to the fact kits tend to drain oil from the pan and motor to circulate around the turbo. I get that.




But why don't people/kits have a self circulating oil system for the turbo separate from the already heat filled engine oil?


Wouldn't it make more sense to have a separate oil feed to circulate cooler oil around the turbo. Than to take hot oil to cool down something hotter and send that back into the engine which is already trying to stay cool and dissipate the heat that's already present?


To me that's like adding water to a flood.




Am I missing it? Or why aren't people using self circulating separated turbo dedicated oil systems to help keep excess heat from heating both turbo, and motor more than they already are on their own?!

iideadeyeii

iTrader: (6)

The oil would be hotter if it had it's own system. /end thread

CK_32

iTrader: (1)

How is that? Even if it had its own dedicated oil cooler?

2one8

iTrader: (1)

You could, but that's added cost, maintenance, complexity. Plus turbos get hot, much hotter than most areas of the engine, so the engine acts as a cooler compared to the temps of the turbo, and by having a large capacity of oil and cycling it through the engine that is also being water cooled, it brings oil temps down more that if it was a smaller capacity self contained system with a single cooler. Add an oil cooler to the pre-existing system and temps are even lower.

iideadeyeii

iTrader: (6)

^^ This ^^ Didn't want to explain it, haha

ge35es

also...
the what comes out of the bottom drain of a turbo is closer to being like a milkshake so you want at least 1/2 to 5/8 (or more) of a direct gravity fed drain to the hi and dry area of the oil pan. Putting any kind of a cooler in line will back up the drain and probably cause the oil to cook the bearings in the turbo. Safest bet is to add an oil temp gauge and monitor it under heavy use then if necessary add a proper oil cooler setup to the engine and call it a day.

rcdash

iTrader: (18)

^ The cooler would be pre-turbo, not post-turbo. That said, for ball bearing turbos, the volume of oil is so small, it does not matter. For journal bearing turbos, the oil does the cooling work, but if you have an oil cooler pre-turbo, it will work just fine. No need for extra parts.

TT03Z

2one8 said it right. If you're worried about the oil heating to much add an oil cooler preferably a thermostatic oil cooler so the oil reaches operating temp before it's cooled. As far as the water cooled turbos go all ball bearing turbos are water cooled and oil lubricated. Journal bearing turbos can also be water cooled but most are oil lubricated and oil cooled. Journal bearing turbos are what turbo timers are made for. Most water cooled turbos don't require cooling time like the oil cooled turbos do because the water will cool the turbo enough so that the oil doesn't coke up in the turbos. Either turbo is good ball bearing turbos generally spool a little quicker but are also more expensive.

bealljk

iTrader: (13)

I think everyone touched on it ... but complexity ...

Also - heated oil isnt necessarily a bad thing ... oil lubricates best in the 190 to 210 degree range ... it's possible to under-heat your oil.

I run a small oil cooler spliced in between my block and my feed lines ... but I'm bat **** crazy...

To add some validity to the initial post - ATI Procharger (yea, a supercharger) and the STS turbo kit are self contained / engine oil-less systems...

Final thought/something to consider ... turbos are subject to heat but if you control your exhaust temperature before it gets to the turbo (via conservative fuel tuning, a reasonably cool intake charge, running your turbos in their peak efficiency range and ample engine cooling) you can eliminate the problem before it becomes a problem...

Resmarted

iTrader: (2)

Because you'd want two exa (gear driven electric oil pumps) to make sure you had constant pressure. The engine is going to be much stronger for pushing oil than anything else you can imagine (it's literally crank driven). And flow is critical to dissipating heat. Basic thermo dynamics, the two ways you can increase heat transfer, is by increasing flow, or increasing the temperature difference (in this case cooler outside air).

Beyond that, turbo's are designed for specific oil pressure out put. I basically had designed a stand alone oil system and ditched it before I even tried. And there are people who run it. But then you run into issues with making sure the turbo has constant *Correct* oil pressure. The turbo doesn't like super high oil pressure at low turbine speeds (can cause premature leaking/failure), and if the pressure isn't high enough at high turbine speed, the turbo will sheet the bed.

So it's just not a practical idea unless you have a remote mounted turbo (ie rear mount specifically and have a lot of room). Takes more parts, more likely to fail, more weight, and is a headache to get right.

If it's a concern, you're far cheaper option is to just get an "oil-less" turbo. They've come a long way even since I started messing with my car.


You're going to be in for it, if you can't figure this much out on your own pal, so better start doubling up on your research.

finewayne

turbos make the oil hotter..