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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: rodpaslow on February 18, 2014, 07:56:35 am

Title: water cooled turbo
Post by: rodpaslow on February 18, 2014, 07:56:35 am
I'm looking at using a water cooled turbo.  Do you plumb it into the return line of the heater core?  i have not seen stock VW water cooled turbo's, just wanting to know how to feed it?

Thanks
Title: Re: water cooled turbo
Post by: monkey magic on February 18, 2014, 08:30:26 am
Not that I know first hand, but surely it would have its own circuit, like a charge cooler. If you plumb it into the heater core it becomes a water 'heated' turbo instead? Or have I missed something here?
Title: Re: water cooled turbo
Post by: rodpaslow on February 18, 2014, 10:29:49 am
I'm sure it goes into the engine-rad circuit and not one by itself.  Water at 200°f is still much, much cooler than the average of 675°f min that my current pyrometer shows with my current setup runs at, at cruising speed.  Why would you do it separately?  Then you have to have another pump, rad and tank minimum. 

I'm just wondering were the in or to turbo line comes from and the out goes were - I'm just assuming the out or 'to pump' circuit from the heater core?  Goes to turbo and return from turbo in the same line?
Title: Re: water cooled turbo
Post by: monkey magic on February 18, 2014, 10:54:53 am
675F is that the temp of the turbo itself or the gasses within? You're probably right, as I said I don't actually know.
Title: Re: water cooled turbo
Post by: RabbitJockey on February 18, 2014, 11:36:12 am
when a friend of mine ran a water cooled turbo he added a fitting to one of the freeze out plugs on the block (for the feed) and then ran the return to the return for the heater core,  but honestly i don't see why you couldn't just T into both heater core lines.
Title: Re: water cooled turbo
Post by: Toby on February 18, 2014, 11:59:04 pm
The heater core circuit would probably not be the best place, since they usually have a valve to shut off flow to the heater core in warm weather.

Ideally you want it to auto-syphon when the car is shut off, so the water should feed from below and exit to a high spot in the cooling system. 2.3T Fords are supplied from a fitting low on the block and exit out the top of the turbo to the radiator side of the T-stat housing.
Title: Re: water cooled turbo
Post by: rodpaslow on February 19, 2014, 05:31:43 am
I could definitely have something made to feed it/lowside from a coolant plug, that would be relatively easy for the machine shop I work at.  returning to the rad may be somewhat harder..
Title: Re: Re: Re: water cooled turbo
Post by: vanbcguy on February 19, 2014, 06:57:12 am
The heater core circuit would probably not be the best place, since they usually have a valve to shut off flow to the heater core in warm weather.

No such valve on the Mk2+ cooling system. Coolant always flows through the heater core regardless of temperature / heat settings. I hear tell that the Mk1 does have such a valve but I don't own one to verify. Most non-VW vehicles I have owned did have valves like that.

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Title: Re: water cooled turbo
Post by: RabbitJockey on February 19, 2014, 07:30:01 am
you would obviously have to T before the valve...
Title: Re: water cooled turbo
Post by: rodpaslow on February 19, 2014, 07:50:50 am
This is on a MK3, do the coolant continuously circulates through the h. core. No valve on a MK3.
Title: Re: water cooled turbo
Post by: TylerDurden on February 19, 2014, 08:03:42 am
Not sure I'd want to use heater water for cooling.

FWIW, I believe the Saabs pull the water supply from the pump (or block, earlier) and return to the head near the upper rad hose.
http://photo.platonoff.com/Auto/20051010.Saab_NG900_Turbo_Replacement/?all
Title: Re: water cooled turbo
Post by: bbob203 on February 19, 2014, 08:12:04 am
I think using the outbound heater core water would be fine? It is most certainly the lowest temp aside from outbound radiator???
Title: Re: water cooled turbo
Post by: 745 turbogreasel on February 19, 2014, 01:46:03 pm
Seems to me in all the factory systems it is a parallel circuit to the heater core, and may or may not share  some of the hoses..
Title: Re: water cooled turbo
Post by: JerryGTD on February 19, 2014, 02:48:57 pm
Apparently the MK2 GTD also uses a secondary water pump as well.
Title: Re: water cooled turbo
Post by: rodpaslow on February 20, 2014, 07:58:28 am
If it needs a separate pump sounds like a lot of extra work.  I've read supposed to be increased life out of water cooled turbo - but is it that much better life?