Electric water pump cooled Turbo

[RetroRacing]

Designed in my head, parts are on the way!
The issue is/was that the water steams off the turbo after coming in off the track, which means it will during a pit stop. Now, I know this is how it is supposed to work, but in my dark and scary mind, it could be better. So, installing a remote electric, stupidly expensive brushless inline water pump to run water through the turbo powered off of a temp switch that is inline between the turbo and degas tank. The pump is wired in such a manner that it will keep running until the water coming out of the turbo is less than 180 degrees, which should save wear and tear on the turbo. Mini, BMW and Range Rover all run this system, among others, so I'm optimistic that it will work.

Thoughts?

[RetroRacing]

That's Water Pump, Pater pump is used for something totally different.

[Zach34]

What do you think of the feasibility of just running one of those Davie's electric water pump kits? They don't seem super popular for some reason.

I used a Meziere electric pump on my Roadster, and it was fantastic. Through a couple track days, temp never got over 180. Makes burping the system easier (you can hear the pump priming and air bubbles cycling through without having the engine on, generating heat) - assuming there is a small bypass opening in the thermostat (like a 1/8" hole). Since it was all key-on ignition-powered, you could turn off the engine and just leave the key on to cycle coolant and keep the radiator fan going. Made so much more sense for racing.

[Sgt.Gator]

Possibly another potential failure point with little or no benefit?

You can also hook up a electric oil pump for the turbo. If it's a separate system with it's own tank and mini cooler it's the only way to be sure the turbo bearing is ok the next time metal finds it's way into the engine oil.

[DanielsDM]

Both approaches are interesting. Shutting off an engine with a hot turbo can cause problems if the oil "cooks" in the bearings and leaves deposits. I had an older turbo subaru that the previous owner had installed a turbo timer that kept the car running for a minute after the ignition key was turned off. Those don't seem that popular anymore so maybe turbo designs have improved. For racing, I can see it being an issue if you had a pit stall at the beginning of the pit lane and essentially no cool down time before shutting it off.

[Mechie3]

Both approaches are interesting. Shutting off an engine with a hot turbo can cause problems if the oil "cooks" in the bearings and leaves deposits. I had an older turbo subaru that the previous owner had installed a turbo timer that kept the car running for a minute after the ignition key was turned off. Those don't seem that popular anymore so maybe turbo designs have improved. For racing, I can see it being an issue if you had a pit stall at the beginning of the pit lane and essentially no cool down time before shutting it off.

Most recent turbo Subarus (2002+) have the water header tank on teh intake manifold. When the car is turned off, water circulates via temperature differentials pushing hot water up that creates a vacuum and sucks cool(er) water in. No turbo timer should be needed. It was more of a thing for oil only turbos on other makes.

[DanielsDM]

Thanks for the info Mechie. I'm not looking at the layout of the system right now so I haven't wrapped my head around how it works yet. Do you think the coolant system mods done for the 818 will affect the process, particularly adding a hole to the coolant tube to help with burping the air out?

[Mechie3]

That shouldn't change how the stock system works.

[RetroRacing]

Water pressure from the stock water pump can push past the inline pump, which is a Dedenbear, so even if it pooches, the turbo will still get water when the engine is running. The pump is mainly for keeping the turbo alive after pit stops, as the oil will go to OMG hot, cook, then its hit again with cool (100 degree water) shocking the crap out of it when we restart it hot after sitting for 30 seconds. Would love to do oil as well, but can't think of a redundant system that wouldn't burn out the electric oil pump.

[DanielsDM]

Now you got me thinking of ways to do it.
Since you have a dry sump now, where does the oil go to after leaving the turbo? If it were routed back to the DS tank then you could add a small pump that drew from the DS tank, pushed through a check valve and then tee into the supply line to the turbo. When the engine is running the pump would be off and the check valve would prevent the normal flow of oil from going backwards through the pump. When the engine is off and the temperature switch (installed in the return line) is closed the pump would run and circulate oil from the tank thru the turbo and back to the tank. Just thinking out loud here.

[DanielsDM]

I thought more about this on the way home.
A second check valve would be required, in the main oil supply line going to the turbo upstream of the tee. This would keep the auxiliary pump from sending oil back to the motor.

[Zach34]

Seems to me an auxiliary oil pump on a coolant-cooled turbo would be unnecessary if you are doing the auxiliary pump on the coolant side. Wouldn't circulating the coolant through the turbo after shutdown be enough to keep it from cooking the oil?

[DanielsDM]

Neither are necessary, the OEM setup works well enough on a street car. For endurance racing where you run the car hard for 2 hours, exit track and pull into the pit and shut if off to refuel, change tires and drivers. It could be as little as 20 seconds from backing out of the throttle to ignition off. Will the OEM system handle that? I don't know. Will a auxiliary coolant setup handle it? Probably. Retro is interested in both so I'm just throwing out some ideas on how an oil system could be done.

[phil1734]

From a cost/complexity/leak issue it seems like you'd be far better off just replacing your turbo every 5,000 miles or so, but that's just me.

Of course, if you want to do this as a fun sort of experiment just to see if you can do it and it works then go for it!

[SixStar]

This is what I have on the AEM 818R.

https://www.rallysportdirect.com/part/water-pumps/dav-30271861-davies-craig-electric-water-pump-kit-with-install-kit

The car is 180-196F always. Running. Driving. Idling. Never deviates.

I strongly recommend this for all 818s

[RetroRacing]

You guys rock, and I too thought of the oil pump in line with a check valve. Problem is that the electric pump pressure would have to exceed the engine oil pressure to open the one way valve, which would stress the pump. I think better in this case is probably best, in that running water through the system during shut down will help.
What also brought this to our attention was what happened to Dragonfly with their turbo. If I could trust a full electric system to last 25 hours, then we would go that way, but electrons are fickle *******s at the best of times.

[iblackwe]

This is what I have on the AEM 818R.

https://www.rallysportdirect.com/part/water-pumps/dav-30271861-davies-craig-electric-water-pump-kit-with-install-kit

The car is 180-196F always. Running. Driving. Idling. Never deviates.

I strongly recommend this for all 818s

Whereabouts did you mount yours? I have one waiting to be installed and I am trying to decide between right next to the battery in the front or at the 90* corner where the gas tank fill tube is utilizing the orientation of the pump to make that corner. I believe those two locations do follow the lowest point in the system and are on the cool side of the radiator as well. Any suggestions or advice?

[SixStar]

Here's where mine is:

62602

[iblackwe]

Here's where mine is:

62602

Okay and thats just going to be a free floating mount then? That 90* adapter you have their is part of the kit or did you pick that up elsewhere?

Thanks

[SixStar]

Okay and thats just going to be a free floating mount then? That 90* adapter you have their is part of the kit or did you pick that up elsewhere?

Thanks

It hangs off my coolant pipes but they're ridged and mounted securely just out of frame. The pump weighs less than a lb. The 90 is an optional part Davies Craig also sells. I bought two just in case and only ended up needing one.