Question for a mate of mine.

Would the coolant diverted from the throttle body into a Y piece. Be substantial enough in speed and volume (or flow Q=Av) to cool 2 turbo's.

Also how much would it be to get oil lines custom made for the same set up? ie drill into pan 2 feed 2 returns.

Thanks

i always was under the impression that it was the oil that cooled turbos
not coolant as in the coolant in the radiator?

but in saying that - i dont have a turbo nor any experience with them so im probably wrong.

the subject of oil and water cooled turbo's is a much of muchness, for instance Garret have water and oil CHRA (bearing housings) on all their turbo's, yet Turbo Giant Trust, still use to this very day, plain journal bearing oil cooled and lubricated only, such as the turbos on evos and the like.

has your mate sorted the oil feed for the turbos yet? that would be the hardest job, as coolant isnt really required, even if the turbo charger comes water cooled, its more likea buffer. Anyways, getting feed and return from the heater hoses is suitable, and factory locations for alot of Nissan factory turbo engines.

the returns are easy, just plumb into the sump

good luck

the returns are easy, just plumb into the sump

good luck

Yep, easy as. Drill into the sump, weld some bits of pipe on, attach rubber / braided hose from oil return on turbo to the pipes you just welded to the sump.

Now that I think about it - I'm not even sure mine have the water hooked up :confused: . I know where the oil comes from and goes to...... but can't picture the water. Will have to look at that tomorrow.

cool beans thanks

Yeah coolant lines are just a good idea as no turbo timer will be used.

Might have a look at yours from underneath mike before holes are drilled.

thanks
That is all

Just for the record of stupid questions. No, you cant just oil cool a turbo that was designed to be water cooled.

Just for the record of stupid questions. No, you cant just oil cool a turbo that was designed to be water cooled.

Its not a stupid question.

Also, disregarding the fact that it has coolant galleries and fittings for water cooling, what are you basing your opinion on?

for the op's peace of mind that is.

Okay - for peace of mind, I just checked. The front turbo definitely has water and oil going thru it, and I assume the back one does too, I just can't see it.

Just for the record of stupid questions. No, you cant just oil cool a turbo that was designed to be water cooled.


Simple answer, yes you can run a turbo without water hooked up. they have been doing it for years....... Just not as efficient because it gets hotter, and cuts its life down.

techincally you can run your motor without coolant also. :nuts:

I reckon its alot more important for a bush-type turbo rather than a roller (as they generate more heat anwyay, and a roller is much more precise), but if the provisions for it are there. you run it, its as simple as that. I know for a fact (checked it with an infrared temp thingy)on my turbo, the centre housing where the oil/coolant galleries are never gets over 100degrees. Whereas the exhaust housing sits at 280degrees C just at idle. Turbo's can get RED HOT, so we're talking over 700+degrees C. Anyone know the thermal expansion rate of the materials used for the bush/shaft if the centre housing temps were not maintained?
I think you'd get some effect on the strict tolerances that they are manufactured to, leading to premature failure. when your turbo is spinning at 60,000 - 150,000rpm you do not want the shaft flopping around like a **** in a sock.

techincally you can run your motor without coolant also. :nuts:

I reckon its alot more important for a bush-type turbo rather than a roller (as they generate more heat anwyay, and a roller is much more precise), but if the provisions for it are there. you run it, its as simple as that. I know for a fact (checked it with an infrared temp thingy)on my turbo, the centre housing where the oil/coolant galleries are never gets over 100degrees. Whereas the exhaust housing sits at 280degrees C just at idle. Turbo's can get RED HOT, so we're talking over 700+degrees C. Anyone know the thermal expansion rate of the materials used for the bush/shaft if the centre housing temps were not maintained?
I think you'd get some effect on the strict tolerances that they are manufactured to, leading to premature failure. when your turbo is spinning at 60,000 - 150,000rpm you do not want the shaft flopping around like a **** in a sock.


Not getting in a **** flinging comp.... Bush type turbos are alot more robust than you think.
As i said befor. TURBO's have been run without water for manny manny years. I have known people to plug up thier turbo water inlet/ outlets because they are not needed, Yes if it has provissions it shoud be run, it will keep it cooler and last longer in aswell. The oil is sufficient to keep the center housing cool and bushes lubed.
TRUCKS have used this technology for a long time.

Now ball bearing turbos dont like the heat so much and therefore NEED the water!

Now ball bearing turbos dont like the heat so much and therefore NEED the water!

Well no, a bearing is much better at handling heat, going through many hardening/quenching process during manufacture etc.. they are made not to be affected by heat, (to an extent obviously, a red hot, unlubricated bearing will fail in no time)...My mates Garret GT35/40R bearing turbo has no water cooling provisions at all. and Garret actually state that oil feed into the turbo should be through a hole no bigger than 1mm. Which we rang up and questioned the garret rep just to be sure... to me this says that very little flow is actually required through it because little heat is produced. Proof enough is that when you stop the motor in his car the turbo continues to spin for another 30 secs, where as my bushtype stops pretty much straight away, which goes to show the difference in friction.

its bizarre to me that someone would block up the coolant galleries because they "arent needed". what are the benefits of NOT running cooling? surely u just said yourself that not running it will reduce the life so then why would you purposely want your turbo to not last as long?

That 1mm hole is so your engine maintains oil pressure with a turbo. if you were to run say a 10mm fitting to the turbo you would loose all pressure to the heads.... Big no no. Hense the restrictor.

I can't tell you why they blocked the water off, but i know it worked for a few years before he sold the car and there was nothin wrong with it then....

It was a high mount turbo so maybe he had air pocket issues with coolant.... i cant remember.

And back to the original question... i think the y peice from the throttle body will do the job, but most people plumb straight from the water pump or thermostat.

EDIT yes a bearing is HARDER because of the heat treatment... but sorry to dissapoint but when exposed to high temps again it then Looses this and breaks down.... When heat is added to metal it changes the structure of the molecules unless cooled accordingly, causing fractures...

I think this says it all.


Garrett ball bearing turbochargers require less oil than journal bearing turbos. Therefore an oil inlet restrictor is recommended. The oil outlet should be plumbed to the oil pan above the oil level (for wet sump systems). Since the oil drain is gravity fed, it is important that the oil outlet points downward, and that the drain tube does not become horizontal or go “uphill” at any point.

Following a hot shutdown of a turbocharger, heat soak begins. This means that the heat in the head, exhaust manifold, and turbine housing finds it way to the turbo’s center housing, raising its temperature. These extreme temperatures in the center housing can result in oil coking.

To minimize the effects of heat soak-back, water-cooled center housings were introduced. These use coolant from the engine to act as a heat sink after engine shutdown, preventing the oil from coking. The water lines utilize a thermal siphon effect to reduce the peak heat soak-back temperature after key-off. The layout of the pipes should minimize peaks and troughs with the (cool) water inlet on the low side. To help this along, it is advantageous to tilt the turbocharger about 25° about the axis of shaft rotation.

Reduced Oil Flow – The ball bearing design reduces the required amount of oil required to provide adequate lubrication. This lower oil volume reduces the chance for seal leakage. Also, the ball bearing is more tolerant of marginal lube conditions, and diminishes the possibility of turbocharger failure on engine shut down.

techincally you can run your motor without coolant also. :nuts:




Still spins me out that most group 1 drag cars don't run radiators.

Still spins me out that most group 1 drag cars don't run radiators.


They are cement/resin filled most of them..... My old boss cooked his motor cause the bloke next to him took too ling to stage....:doubt: 10grand on the line.

For the OP (excuse my ignorance for not replying directly to the question before lol)

Throttle body coolant hoses are a good spot to tap into; just make sure your mate doesnt tap into any heater hoses that run directly to/from the heater core - as coolant flow changes with the heater tap open %.

As for the turbo cooling.. i was under the impression (what i've been told by somebody) that turbo's designed with a water cooled core are generally not good to be run as oil/air cooled units only, as the housings are designed to be less thermally efficient in dispersing radiated heat. :confused:
Water cooled turbos on production cars are usually used when the turbo has to be crammed somewhere where it generally cant radiate and disperse more heat (by air flow) than it conducts.
Why have a large pocket filled with hot air in the core of the turbo?