BNR S4 Build with External wastegate

darkmx-6

Greenie N00B Member
Greenie Member
My MS3 has issues. Lots of maintenance issues. I just want it to be reliable. So I bought a BNR S4 :sweatsmile:
Now that I have this turbo i find out that BNR also rebuilds stock replacements for +- $450. :smash2:

Had I know this I would have done that since my goal is not to make the most HP around, but stop it from burning oil out the tailpipe.
Originally I figured if it cost almost $1000 for a stock turbo why not upgrade?

So hear we go!
The BNR S4 looks great, but right off the bat the coolant feed line that came with the turbo has to be bent for it to be in the proper place above the compressor housing. :watchout: Why was it not the right size to start with I don't know.

Besides having to bend the coolant line that came with the turbo and the stock coolant return line, the turbo bolted up in the stock location without a problem.

And then there was a problem... :confused:

IMG_0009.jpg
The copper washer doesn't fit the stock banjo bolt.
I ended up tightening it down and it pulled it into place and i think it will be ok.

And then there was another problem...:eusa_doh:
My S4 does not have the internal wastegate. ( not the problem)
Since I was having over boost problems with the stock turbo I wanted to make sure that doesn't happen again and got a custom S4 with a external gate.

This is the probelm: The vband flange is right where the bolt hole for the stock support bracket was.

So I made my own bracket.
IMG_0010.jpg IMG_0011.jpg IMG_0012.jpg
I used longer bolts to make sure it was grabbing enough threads on the turbo.

and then there was a real problem.... :hum:

So far everything else has been easy.
But now the downpipe over laps or hits the wastegate it's so bad that I need to cut a section out of it to make it work or somehow make a sharp bend at the wastegate flange so i can miss it.

Is this what I get for buying a cheap ebay downpipe?:sob:

I have some fabrication skills but they are very, very limited. So this is going to be a real challenge for me. I also do not have a tubing bender, or way to back purge the pipe. To avoid this problem, I bought some solar flux to keep the inside of the stainless exhaust from sugaring.

First thing I need to figure out is the size of the wastegate flange on the turbo. It is for a 44 mm tial type wastegate, but it is bigger than 44mm. The outlet on the wastegate is 44mm.
I need this so I can start making the sharp bend.
Why do they not make the inlet and outlet the same size? I don't know.

Anyone know what size it is? I got to be out of town for the weekend, but next week I'll use my digital calipers on it to see what size it is.

I'll also take more pictures so you can see what I am talking about.

See you all soon!
 
If anyone is interested in the brackets let me know. I better read the FAQ about selling stuff before I go too much further...
 
Im just curious, I live in the uk and only s4 with IWG are available so I’m wondering where you got your s4 with a EWG
 
you dont need the turbo to have an EWG, you can get an exhaust manifold with a provision for EWG and bolt the turbos IWG shut
 
How would you bolt it. Would it be a case of remove the iwg and weld the hole?
 
you can buy a bracket that just bolts in or weld it if you are so inclined. personally i would bolt it in case you ever wanted to go back
 
I had purchased a Grimmspeed bracket for a WRX or something like that. It worked on my BNR turbo. The plate that bolts to the compressor housing was slotted so it could fit a variety of turbos. The back section just gets turned with a wrench until the waste gate arm/flap is fully seated against the turbine housing.

It fit without issues using the XS Power manifold and TiAL EWG
 
Don’t suppose you have a link to the correct bracket or a website do you. or any suggestions on what to search
 
Well after a lot of welding, fitting and more welding, I got the turbo in. A few months ago.

But my car still smokes.... looks like the problem all along was the engine not the turbo. cylinders 2-3 oil rings are bad. Looks like it needs a rebuild but I'm going to try some fixes from project farm to see if it makes a difference. So far sea foam hasn't make a difference.

Can anyone suggest an engine rebuild thread I can follow?
 
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