Now that I have spec'd my build, I'm working on the more detailed parts.

After hours of reading on here and elsewhere, I'm still lost in some respects to the fluids for this turbo. I'll start with what I have found with my research;

Oil feed - To take from oil pressure switch with a T piece adapter from the rear of the block. This should be a -3AN fitting with a 0.40 restrictor.

Oil return - Ideally a -10AN with the return welded into the sump ABOVE the sitting oil line.

Water feed - To take from the cap at the front of the block (not sure what its called) have been told by the turbo supplier this should be a 14-16MM ID pipe.

Water return - To weld back into my alloy RAD.

Now my questions/uncertainty .. The oil side, I am reasonably confident in what I have found, unless anyone has anything to input to what I have listed above?

The water however, I have read on Garrett's website that the turbo should be tilted 20 degrees with the feed at the bottom, return at the top. Now, should the return continue to go up, or come back down? I want to have the fitting welded into the rad shortly, should the return be welded into the top of the rad, or the bottom?

Also, is someone able to tell me what a 14-16MM ID pipe is in AD? I assume that AD is just a measurement?

Any help is appreciated.

Thanks,

 

If you go this route, make sure you use a Steel 1/8 BPST fitting to go into the block, and ideally remote mount any pressure sending unit for gauges so you dont create the situation for cracking fitting or aluminum block.


More importantly is that the CHRA is as straight as possible, and the drain is as straight with no uphill slope or sharp 90's

Going from this fitting to -6an is how I have mine





I'll let shodan comment on the tilting of turbo, but weld the fitting to the bottom of the radiator. You want the water to flow from Hot to cool.

 

Lightning Teg - Thanks for your input, really appreciated.

Note taken for the oil feed. Thanks. I was thinking about oil pressure gauge, by remote mount, do you mean like a oil filter relocation?

Agreed with the downhill slope for the return. The rotation of the CHRA however, is very much open to debate! Especially after reading Garrett's recommendations about tilting the CHRA 20 degrees for the purposes "Thermal Siphon Effect"

Your coolant feed, could you give me some more details/specs please? Thats exactly how i want to do mine.

Thank you!

 

He means the gauge. Not the Oil filter itself, as you're suggesting. Lightningteg is simply suggesting that you put the oil pressure gauge somewhere else and not at the adapter block that the oil feed line comes from.

As for the 20* degree angle for optimal siphoning effect... Ignore it. Concentrate on the CHRA being as vertical up/down as you can. The water siphoning effect will still occur. Sometimes I wonder why the post that part of the information.

What lightningteg is referring to is what is called a "freeze plug block adapter".. It looks like this: (And so happens you can get it at the same place, too).

-10 B-Series Block Plug Adapter

The same company sells the entire water cooling kit, which includes that same freeze plug adapter. So its best to save your money by getting the entire kit.

It also comes with the weld bung needed to put on your aluminium radiator. But you may save some welding time if you know what size your drain plug is, and get the appropriate drain plug size to a -6AN adapter (just make sure that plug has a rubber washer or crush washer to keep from leaking.

Make sure that you choose the banjo kit for "GT" turbochargers. That will save you a LOT of headache when it comes to installation of the system.

 

Shodan, as always, thank you for your input..

Looking through their site (thanks for the link) GT Turbo Coolant Kit thats right yes?

I have a shop that will weld the bung in for me to the Rad. Next question on this one, should the bung be put into the top or the bottom of the Rad? (I am going with a sheepey built mini ramhorn mani so turbo will sit low) is the return gravity dependent or as its plumbed into the water system, it'll be pressurized yes? So wont matter?

Thanks for the note on the Banjo's.

Re the 20* angle .. Interesting, I was thinking that as the oil is gravity drained, being on an angle would mean that there is oil sat, is this your reasoning for your comments too? I thought it was peculiar when I read it.

 

Also, there is an option - "Inlet/Outlet thread size" these are the threads for the turbo coolant holes correct?

 

All GT-R turbos like yours are 14mm to -6AN. (Journal bearing Garrett are 3/8thNPTto -6AN) Get the Banjo kit option!!!.

You need to know your fittings and sizes when doing these turbos. They are too expensive to not get..

You also want to make sure you have the proper oil restrictor type as well as size.

STAY AWAY FROM THE RESTRICTOR PLATES YOU SEE ON E-BAY. See my comments on this thread below.

Post #23
https://honda-tech.com/forced-induct...lines-3253230/

Get the correct Oil restrictor for Honda at 75psi of oil pressure. And yes, you'll need it, don't fall for others saying you don't

GT Turbo Oil Restrictor

they are made mainly for -3AN. If you need -4AN e-mail them to get the right one.

But you need 7/16 -24 restrictor. Don't play games on this trying to go on eBay for "cheaper" or for better convenience . Its not worth destroying your turbo over.

 

Banjo kit will be bought!

I'm trying to get my head around them. If I'm honest, I have neglected the complexity of this part of the build. And your exactly correct, this is too imperative to not get right the first time. I will also be buying the restrictor from B&R. I had read your post in the "coolant & drain lines" thread.

Garrett recommend -3AN for this turbo for its oil feed.

So remaining questions regarding coolant is where to mount the coolant return into the Rad?

 

In fact, it will be this kit from B&R Turbo Oil Feed Kit

With the GT inlet option selected.

 

What kind of radiator do you have?

 

Dual core alloy

 

Find the thread size for the drain plug and buy a "Metric Thread to -6an" and there you go. No welding neccesary. Just get a rubber o-ring or crush washer for it like TheShodan said.

 

Ok mate thanks. Is this the optimum route?

 

we wouldn't say it if it weren't Good luck.

 

Thankyou kindly

 

with the CHRA vertical the siphoning effect won't be as pronounced (even Turbonetics has the 20* tilt in their literature) but for the purposes of maintaining CHRA temperature after engine shutdown (if you don't have an electric water pump) it will be more than adequate.

For the majority of setups having the CHRA tilted that much can cause oil draining issues that are more damaging than not having the maximum siphoning effect through the CHRA. As long as there is a temperature differential between the CHRA and the engine coolant it will circulate.

 

Thanks for the input chaps ..

Just in correspondence now with B&R for getting oil feed & return and their coolant setup chipped over to the UK..

 

I highly suggest the inline filter TheShodan posted. It's so compact it doesn't get in the way (and doesn't require modifying your current feedline unless you are using a hard line and filters very fine particles out while remaining high flow.

This is really a must if you are running an oil feed before the oil filter like you are planning, as this sends dirty unfiltered oil into the CHRA where the oil passages are only 2-3mm in diameter and with tolerances between bearing and shaft being in the thousandths it doesn't take much to clog a feedline or oil passage.

 

Yes, agreed .. You mean something similar to this ? Earl's Performance Products UK - Oil Filters 140 Micron obv 3AN ? However they dont do seem to do one that small .....

 

Scrap that, i've found it

Inline Oil Filter - Woodward Machine