Just wondering if anyone ever thought of / or did use a setup where the oil, before being sent to the turbo, is run through an engine oil cooler? Thinking that would help the turbo... See image attached. The loss of pressure from the oil radiator could be compensated by using a high-volume oil pump...?
Cooling oil before sending it to turbo...?
- Thread starter gdouaire
- Start date
Buick Mark
Active Member
- Joined
- Sep 12, 2001
I imagine you could, but what would be the benefit?
Ideally the oil should get up around 180-190 degrees so that the moisture vaporizes out of it. Typical hot cruises or towing situations may see oil get into the mid 200's for periods. Having clean pressurized oil is more important than cool oil. Cool poor flowing oil may actually cause a lot of heat to build up in the turbo because there isnt enough flow through the cartridge to cool it. So 180-190 oil at 30+psi should suit your turbo just fine as long as it is clean and uninterrupted.
You should see how hot the oil is leaving the turbo. .. I suppose putting a temp gauge on the discharge to gather data couldnt hurt....
Then you could better determine if this would be beneficial. ...
Or even better put one pre and another post turbo... This way you could determine temp increases and delta's for your oil. ..
Sent from my SPH-L900 using Tapatalk 2
Then you could better determine if this would be beneficial. ...
Or even better put one pre and another post turbo... This way you could determine temp increases and delta's for your oil. ..
Sent from my SPH-L900 using Tapatalk 2
If you cool the oil excessively it gains viscosity and flows less volume and pulls less heat away therefore cooling is compromised. 180-190 degrees is where the oil is happy.
A bigger pump won't move more oil. Oil flow is a factor of pressure, orifice size and viscosity.
I kinda see where you're going but turbos routinely last for hundred of thousands of miles as they're set up now.
I guess if you really really wanted to send cooler oil you could get an aluminum extrusion with heat sink fins to replace the stock feed line. Run a duct from behind the grill to send ambient air to the new cooler feed line then exhaust it at a low pressure area under the car. I also wouldn't expect any benefit from doing that. Keep in mind even really hot oil is still cool from the turbo's point of view.
Cooler oil will have higher viscosity (thicker). Thicker oil going through the high speed journal bearing will cause two things...
1. There will be more fluid friction in the journal bearings. This will cause the temperature increase of the oil flowing through the bearings to be higher. One could argue that turbo efficiency and spool up will be slightly lower.
2. The volume of oil flowing through the turbo will be lower. Thus, it will remove less heat.
These two effects will offset the temperature gains you are trying to get by cooling the oil.
Granted, I usually run 20W50 in my car, so I already have done something to create the above two issues, anyway :-(
Posted from the TurboBuick.Com mobile app
1. There will be more fluid friction in the journal bearings. This will cause the temperature increase of the oil flowing through the bearings to be higher. One could argue that turbo efficiency and spool up will be slightly lower.
2. The volume of oil flowing through the turbo will be lower. Thus, it will remove less heat.
These two effects will offset the temperature gains you are trying to get by cooling the oil.
Granted, I usually run 20W50 in my car, so I already have done something to create the above two issues, anyway :-(
Posted from the TurboBuick.Com mobile app
The sandwich adapter (oil feed) has a bimetal thermostat in it. This opens and closes to divert oil to the cooler for the exact purpose of keeping it at the ideal temperature. That's the whole point.
But get a "heavy duty" cooler, like for a performance SBC. There is no loss of pressure. And run all the oil through it, not just for the turbo. Keeping all the oil at the right temperature will help cool the entire motor.
BTW, it's supposed to go through the filter after the cooler.
Finally, the high volume mod only helps at lower RPMs, where you don't need it. At higher RPMs, the pressure relief limits volume along with pressure.
And according to engine rebuilders (not my personal knowledge), you should avoid the high pressure 60 lb spring, as that will wear the front camshaft bearing and distributor drive; stick with the stock pressure 40 lb spring.
But get a "heavy duty" cooler, like for a performance SBC. There is no loss of pressure. And run all the oil through it, not just for the turbo. Keeping all the oil at the right temperature will help cool the entire motor.
BTW, it's supposed to go through the filter after the cooler.
Finally, the high volume mod only helps at lower RPMs, where you don't need it. At higher RPMs, the pressure relief limits volume along with pressure.
And according to engine rebuilders (not my personal knowledge), you should avoid the high pressure 60 lb spring, as that will wear the front camshaft bearing and distributor drive; stick with the stock pressure 40 lb spring.
I like that idea. And there are a lot of other things that were posted by other people here on this thread. Thanks. There are things to evaluate for sure before going for this
The stock spring isn't a 40psi spring and I wouldn't follow this advise. If you have a 6000rpm engine you don't want pressure relief until 70-75psi. I've been running a blue spring or in some instances blocking the relief circuit and not had cam bearing or distributor drive failure. Using the correct oil viscosity making sure the oil is hot before revving, and having a properly setup cover are what's important.
Posted from the TurboBuick.Com mobile app
^What bison said. That's an overly simplistic statement with specifics. They never get it right 100% of the time.
If you're really interested in logging in and out temps, that's easy. Get this, thermally couple it to the feed line and the drain line. Hook it to a powerlogger or some mini volt meters and you can see the DeltaT in real time under all conditions.
http://turbobuick.com/forums/thread...-probe-for-powerlogger-or-freestaning.396926/
I have a feeling you will be surprised just how uneventful the data would be.
I like that idea. And there are a lot of other things that were posted by other people here on this thread. Thanks. There are things to evaluate for sure before going for this
If you're really interested in logging in and out temps, that's easy. Get this, thermally couple it to the feed line and the drain line. Hook it to a powerlogger or some mini volt meters and you can see the DeltaT in real time under all conditions.
http://turbobuick.com/forums/thread...-probe-for-powerlogger-or-freestaning.396926/
I have a feeling you will be surprised just how uneventful the data would be.
Rebuild kits come with a 40 lb spring for stock replacement, which gets about 38 lbs. The stock pressure was specified at 38 lbs.
I won't quibble with the rest. I don't know what his goals are. Buick did revise the front camshaft bearing for better lubrication in later blocks. I forget what block he's working with.
The stock pressure relief is not 38psi. It's closer to 60psi. Anyone who uses a 40psi pressure relief jn a 5000+rpm engine is foolish. The cam bearing is oiled the same way in all years. The later cams had no grove and the blocks are grooved behind the bearing.
Posted from the TurboBuick.Com mobile app
You must mean cold startup. When you start up cold, during initial fast idle the pressure shoots way up. With a stock spring it runs well over 50, with a 60 lb spring it's over 70.
Buick specified 38 lbs at 2400 RPM with the motor completely warmed up, oil at operating temperature. That's what I was referring to.
I looked at a video clip I took. Warmed up, with the 40 lb "stock replacement" spring from a kit, it shows about 42 lbs at 2400 RPM. But cold it was, like you say, closer to 60.
Buick specified 38 lbs at 2400 RPM with the motor completely warmed up, oil at operating temperature. That's what I was referring to.
I looked at a video clip I took. Warmed up, with the 40 lb "stock replacement" spring from a kit, it shows about 42 lbs at 2400 RPM. But cold it was, like you say, closer to 60.
Uh, that's what I was referring to. Not exactly "the same way in all years" is it?
Thanks for the feedback, guys.
My conclusion is:
1) will not run a cooler on the path of the turbo oil feed line
2) will run a standard engine oil cooler, however
3) and because i'm running an oil cooler plus turbo, will get a HV oil pump rebuild kit.
4) eventually will monitor oil temp before/after it's routed through the turbo as an "educational" activity.
Posted from the TurboBuick.Com mobile app
My conclusion is:
1) will not run a cooler on the path of the turbo oil feed line
2) will run a standard engine oil cooler, however
3) and because i'm running an oil cooler plus turbo, will get a HV oil pump rebuild kit.
4) eventually will monitor oil temp before/after it's routed through the turbo as an "educational" activity.
Posted from the TurboBuick.Com mobile app
