For the record, this is the build thread for the R2S Turbo system discussed in detail here:

Research stage discussions

Here's what I intended to fit under the hood:






A progressive system made by BorgWarner, primarily intended for diesel applications.
However, I soon found out that BW itself is actually looking into gasoline engine applications, and has even formed a department for R&D.
That encouraged me, and I contacted the chief engineer in charge of that department. He was pretty interested in what I wanted to do, and helped me a great deal.

This project, for the record, is a first of its kind. Meaning, no other idiot (other than yours truly) has even bothered to attempt utilizing this thing in a gasoline (or diesel) powered engine.

To quickly recap my installation strategy, I had decided on the following:

• Custom manifold and downpipe would be fabbed
• All actuators would be vacuum controlled
  • Vacuum circuits, a reservoir, solenoids and programmable outputs would have to be figured out
  • I would have to come up with a strategy to run the turbos in a seamless manner (tall order)
  • Since I would be using ALL available programmable outputs for the turbos, I would have to come up with a way to trigger my electric power steering and other stuff.
• Make room in the engine bay to fit this thing and all its ancillary components
  • Oil feed and drain lines, WG cooling, CAI, etc. all had to fit.
• With two turbos in a confined space, I would need extensive heat management and insulation.
• Tune the engine while increasing boost in very small steps
• Profit.

So I started...

 

Looking forward to what you come up with

 

First order of business was figuring out the vacuum controls..

(I promised Joe I would post all the stupid mistakes I made, so I am not holding anything back here..)

A little backstory:

This system has a total of three vacuum controlled actuators:

• A "gate" between the two turbos to facilitate transition - HP - LP bypass (or turbine bypass in BWspeak)

That's the actuator on the far right in this pic (AKA "big boy")

• A valve that stops compound boost and allows the LP turbo to provide boost in the traditional sense - LP Bypass, or Compressor Bypass

• An internal wastegate.

The small turbo (KP39) spools instantly and provides boost as low as 1000 RPM.
All incoming air is fed through the larger turbo (K04), it spins and provides support for the HP turbo by means of compound boost until it takes over.
The wastegate is funky.. It needs to be open below the 100 kPa level to provide fuel economy. I was told the HP turbo freewheels when the IWG is open and scavenges the exhaust, and that helps the engine efficiency a lot.

 

Cool. This sounds interesting. Glad to see it start happening.

 

Yuuuuuuusss

 

I'm in for $5 toward the resulting dyno run.

Here is a Borg warner by the name of 7 of 9:

 

I got some solenoids and started to look for a safe place to install them - no point in cooking stuff under the hood.

This area tucked in the left fender seemed like the best spot...




Decorating the panel with solenoids..

(Never mind the MAC valve, I had to ultimately relocate it to an even cooler spot)

 

I also made a manifold for vacuum distribution, using some aluminum stock..

 

OK, this thing is vacuum controlled. That much is clear.
A turbo gasoline engine has no vacuum under boost. It has boost.
Diesels are a different story, they have vacuum pumps, and do not care if they produce boost or not.

I need vacuum, so I guess I will make myself a vacuum reservoir...


Take two 20 Cm stainless steel Ikea salad bowls..




Drill 2 holes in one, install vacuum ports.




Gives you 4.2 liters of vacuum volume!



Attempt to weld them together, make a big mess, and run over to Iskender (grand master of welding and fabbing exquisite exhaust systems).
Iskender welds it up while I enjoy my tea...

Re-invent Sputnik in the process...




Fits nicely under the left headlight, behind the bumper.






More on this...

 

Since I would be operating some pretty important stuff with vacuum while the engine was making boost, I began worrying about running out of vacuum.
I mean, what if I was on the gas for quite a while, like going uphill under boost for extended periods, operating actuators all the while, and using up all the vacuum?
That's why I decided I should incorporate a vacuum pump in the system, and program its power source so that it would come on when vacuum was depleted to 60 kPa, and would cut off at 40 kPa.
(I tested the actuators to see their minimum vacuum requirements)


Here's that vacuum pump, testing the system before installation.
It went just to to right of the left headlight, in front of the radiator, in a "cool" spot.
Do not let the size fool you, damn thing draws vacuum down to 40 kPa pretty fast.






That was good insurance.

And then, I just wanted to see how many times my 4.2 liter vacuum reservoir would operate an actuator before it ran out of breath.
Turns out, it had enough (with 30 kPa engine vacuum) to do 30 full strokes. That should be enough without any additional pump, but hey, the pump gives me a piece of mind.

 

Speaking of using programmable MS outputs to control the solenoids, Dimitris told me I could use an NPN transistor to convert any unused IGN output to lowside.
A friend suggested I could use a VW/Audi ignition control module, and just hook up the outputs from MS to it.
The module has very sturdy transistors in it, and I would get lowside outputs to run pretty much whatever I need within reason then.
In other words, I would not have to worry about the load a solenoid would impart on the output.

Neat.

Here's the ignition control module:


I installed that module on the backside of the solenoid panel...




Which turned out to be a total failure...

Turns out, while the transistors in the module does indeed convert a "+" signal to "-", it does that momentarily. Like firing an ignition coil. Just a trigger.
I needed the damn thing to stay put, and be there as long as the conditions required a signal to be present.

It was a noble idea, I just wrote it off to R&D expenses...

 

So, instead of some ignition module, I decided I should use an NPN transistor like Dimitris suggested, but further isolate my MS from any load/mishap by utilizing an optocoupler, as well.
Half this project is paranoia, I swear.

Here's what I did.

I made an aluminum heat sink for the transistor, and secured the said transistor with a RIVET! (Gotta be a first)
Configured the optocoupler for lowside, closed the lid, and I was done.






The optocoupler draws 40 mAh. That's pretty much neglectable...





You can clearly see the flyback diode on the lower left corner in this pic..



I liked it so much, I used optocouplers on all outputs.
Better than a relay.




I even used one on the warning lamp circuit of the alternator to trigger my electric power steering pump. (I have a custom 140 Amp alternator, and it has a conventional lamp circuit.)
That way, the big pump comes on only when the alternator starts charging after the engine is running.

 

I have read a ton of turbo build threads on this forum, and a lot of them either talk about heat management, or share horrible stories of heat damage.
An exhaust manifold is a major heat source. So is a turbocharger.
And, there are 2 of them!

İmages of melting master cylinders, hoses, my feet.. Pretty disturbing stuff.

Guess what.. The bestest, most expensive insulation stuff on earth has air trapped in it. Air.
What if I used air to deal with heat under the car then?


The idea is simple: Make a second trans tunnel. Make it light. Make it a bit smaller than the actual tunnel itself, so you will have air between the the two.

Allrighty then...

Remove engine and transmission, take some 15 mm aluminum strips and knock out a smaller version of the tunnel, leaving about a 10 mm gap...







Once you have the desired form, trim the excess strips, tie it all together.
I used rivets for this job, makes life much easier.

 

Sir, you are nuts.

I love it.

 

Removed the frame and started covering it.
I used 0.30 mm textured aluminum for that. Pretty lightweight stuff.





I riveted the aluminum sheet in sections, taking great care not to distort the frame.
As careful as I was, there was a bit of distortion which gave some problems during the installation, but liberal use of harsh language came in pretty handy.









Nice and shiny, but not for long...

 

I shot 2 layers of grey undercoating on the backside for further insulation and to prevent any buzz/rattling and associated shenanigans...

 

And, I used rivnuts to install the thing in the tunnel. Made my life easier.
Stainless M6 studs in the rivnuts, then stainless nuts..
(A total of 12 mounting points)

 

This is the stuff I used.
I bought 2 1 meter by 2 meter sheets and used the rest on pretty much everywhere.

 

I went ahead and undercoated the bottom of the car while I was at it.
Grey turned out to be an excellent choice. I can see everything while I am working under the car.
And, leaving the trans side of the tunnel I installed uncoated gave me a great shiny surface.
Working on the transmission is much easier now. It's not a black hole anymore.

I have no pictures of the seemingly endless cleaning before I shot the undercoating. Hours of pressure washing and scrubbing, dirt, mud, road remnants running down my arms, crap all over the garage...
Yeah, I wasn't thinking about taking pictures then.

 

This is what I waited for for four months...
There is one person I would trust with my project in all of Turkey, and he is an incredibly busy man.
Iskender builds exotic exhaust systems for some very very high end cars, people bring brand new Lamborghinis, Ferraris, Porsches, Aston Martins, etc straight from the dealer for custom exhaust work.
He is a cool guy, and I know him well.
I went to him to see if he could build me the necessary components a couple days after I received this turbo system, and he told me to bring the car right away.
Knowing his workload, I knew it would take a while.
So, no complaints...
(For the record, he charged me for materials only. What I paid him is nothing compared to what he charges his normal customers...)