Which way should I route the turbo water lines? I found this image and was going to follow this by placing some tee's in the heater hoses. I just don't know which direction the coolant flows. Does the water pump pull water across the water pipe? Or push it towards the thermostat? I've found conflicting answers.


It's a water cooled journal bearing. The max angle Garrett suggests is 15 deg for journal so I suppose I'll put it at 10-15 deg. And if the top hose in the first picture I posted is pulling water then I was going to rotate the turbo 10-15 deg towards the core support.

I have this manifold.

 

The water pipe is on the low pressure side of the pump. I have one fitting coming off the water pipe and the other coming off the bottom of the radiator on my setup. CHRA is as level as I could get it - no angle.

 

On B and D engines there's a port you can use on the front of the block as well that goes directly into the water jacket for the feed, I can't remember if H engines have the same. Tapping the bottom of the radiator for a return bung is usually the best option for the return as far as I know.

 

Thanks for the responses.
Ok so if I'm understanding you correctly then it flows like this?

If so then I was right that I should tilt the chra towards the front. Then hook up the driver side hose to the higher port. Wouldn't you not get any thermal siphoning if you made it level? Now I'm debating to go maybe 5 degrees? 0 is optimum oil drain for journal but need some angle for the siphoning. From what I read the main use of water cooling is after shutdown where the siphoning will keep cooling the turbo which prevents coking. Or maybe for BB turbos because they get less oil cooling? Then again Stock turbo cars like Subies also have water cooled journal bearings which I read were a decision by the engineers to make the car idiot proof. A wide range of people would be driving and they may not cool down the turbo after driving hard.

They don't have a port in the front. There's one in the back.

I was just going to use these barbs https://www.ebay.com/itm/311741827018 and get some bulk 1/2" heater hose to connect to the turbo fittings https://www.ebay.com/itm/264004827687. I've read elsewhere heater hoses are ok for this purpose. Would like some confirmation on that tho Don't you think the radiator hose is too large for these tiny 1/2" hoses? I'd have to splice in a tee. Maybe it is the best return but I wonder if the heater hose will work ok.

 

He's talking about tapping into the bottom tank on the radiator - not the radiator hose.

I honestly think you're over-thinking this. Go with a level CHRA for proper oil draining and give your turbo water from two different places in the cooling system.

 

Is there a least invasive way to do this? I don't have a way to weld aluminum but I have brazing rods. I'd rather splice in a tee such as: Or what about a threading in a barb where the drain plug is?

 

I know @Txdragon was looking at barbs he could put in place of the drain plug, but don't know how far he got. Maybe he'll chime in.

 

That's for a stock radiator. I have a Full Blown 1/2 Rad. It has the plastic wingnut.

https://honda-tech.com/forums/tech-m...-size-2642365/
Guess I'm going to have to drain it and start testing.
You know another guy used the IACV lines.

 

You can thread in a conversion barb based upon the size of the drain fitting of the Radiator fitting, OR you can more easily find a conversion fitting to go to -6AN and head to the CHRA of the turbo.

 

Thanks I'll update in about a week when I start to tinker with it.

 

edit: the barb fits great. It's a 1/4" npt to 3/8 but maybe I'll get a bigger barb size. Which size is best for the water lines? 1/2", 3/8"? I'm thinking to feed from the passenger side heater hose that goes to the head or the IACV line near the thermostat. Then drain into radiator barb.
BTW I got a new turbo: Pulsar gtx3076 gen 2 ball bearing. Should I clock this for thermal siphoning?

 

No. keep the turbo completely vertical

 

Will do
Still curious as to why

 

6an same as 3/8"?

 

I think for oil draining reasons is why the turbo should be kept vertical.

 

Ding ding ding ding....:-)

 

Right I know the oil is completely gravity drain so for a journal it should be as vertical as possible but can still be a little degreed off cause of space constraints. But this is my first ball bearing turbo I thought it would be different as like how the Garrett manual says. I guess angling for siphoning is not all that necessary?

Would it be ok if the water banjos point up?

 

A little eye candy

 

Even journal bearing Garrett can run water-cooled. , so the siphoning angle isn't that paramount. Just optimal, if you can. having the banjos pointing up isn't a problem as long as there is enough pressure to fill the inner CHRA jacket of the turbo.

 

no. its a conversion fitting. Google -AN to inch size charts

 

So you're saying it's not that important but if I can angle it it's optimal? I should have plenty of space to angle it.
Enough pressure - So make sure to have a properly bled coolant system?

6an appears to use 3/8 hose.

A multi page thread with people arguing about siphoning https://www.miataturbo.net/diy-turbo...ispreloading=1
If I point the banjo up for the out side I guess that could achieve the same thing and have a level chra.

Do I connect the hot water side to the radiator barb? Isn't that the cold section of the radiator so I'd be feeding heated water into it reducing the effect of the water cooling however slight it may be. Cold to IACV line or heater hose or coolant neck.?

 

Yes. If you check the Stickies at the top of the forum, There is a specific water-cooling section, and uses a similar write-up. The image you posted is when Turbonetics used to be the only distributor of Garrett performance turbochargers (Before Garrett Motion, and long before Garrett had a separate performance division.. so about 2003. ;-) ) .

It really is best in either scenario to keep the CHRA as completely vertical as possible. Yes, you have a little "wiggle room" to tilt the CHRA to be optimal for water filling the jacket because you are a ball-bearing CHRA, but really, it's not going to matter for the siphoning effect.

Now, as stated in the write-up at the top of FI FAQs section, the important thing to note is to get the water from two separate sources so that the water flows continually through the system, and doesn't route back pre-maturely. Now, whether that is from the TB, Front Freeze plug (using an adapter kit) or radiator, there are some nice ways to do this. But whether or not 2-3 degrees is going to matter, the answer is no. It won't matter as the water's ability to cool the CHRA is really when after the car shuts down, and the exigent heat from the turbine housing transfers to the CHRA itself. Since the water pump won't be operating at this point, anyway, it really doesn't matter whether or not getting a few degrees cooler water is going in. Remember, you're transferring about 800*F heat into a system that is already 700*F or more in the CHRA in the 1st place. Making sure you have the right coolant combination is the more important aspect of your system , then simply worrying about a few degrees of water temperature.

 

Thanks for the excellent response

 

Looks great

 

Thanks lol. I'm making the downpipe right now as well as so many other things. Aiming for 450 but not so sure now as Aradin said 450 will stress the rods. I did make the rings really loose. So the ringlands being the weak point and using e85 I think it will last. And incredible tuner John Kerr Please excuse the blue. It was there from the PO and I couldn't get it off.


Anyone know if it is safe to use a pipe expander on these mandrel bends? They are pretty short 45 degrees. I think this will be better than butt welding them because I believe the weld is the weak point. I'm using a mig with mild wire and c02. Lame I know. That weld near my hand was one I did and it lasted fine and didn't rust since I painted it.