Ok this might look like its been asked 100 times, but this is what i want to know. Everyone talks about the n/a to turbo project (yes i read Aaron thread and is great) i want to know what are the small part that you need that most people overlook when they are adding a turbo to an n/a. right now i am getting a t2 intake, s4 turbo, mani and aftermarket intercooler, but i need to know about the sensors cables fuel pump what size injector so on

Thank you for taking your time to read this.

 

t2 ecu, t2 throttle cable, t2 pressure sensor, t2 afm, t2 oil return line, oil feed line, t2 or better fuel pump, 550cc injectors.

Also if your buying a turbo, why not just buy a s5 turbo/manifold?

 

Cool thank you, but ithought the S5 mani was diferent than the S4

 

It is, the s5 is true twin scroll, while s4 has 2 waste gate actuators. Are you piecing everything together?

 

yes i am doing it little by little, i just got a local guy to do my streetport and assemble the engine. I was going to port myself but i will let someone with experiance do that part.

 

to me is the little stuff that gives me the most problem, i can put it back the original way, but when you add a turbo allot of little things change that goes with any modifications.

 

if you are getting it rebuilt try to source some turbo irons. add the matching front cover and waterpump housing you're in business for a high compression turbo engine. even without the irons get the other two. that way you can just run a line from a aftermarket oil filter pedestal to your turbo oil inlet and be good to go.

doing it this way is a pretty much bolt on affair. the hardest part is port matching the lower intake if you use the stock n/a irons. you can sometimes find manifolds on the forum premade or ported for your block.

 

what kind of hoursepower have you guys seen out of one of these basic set ups with a streetport?

 

to add to this thread. will the stock N/A fuel pressure regulator work for the turbo pump and injectors? Never heard anyone say yes or no.

 

This depends on how you are building things. If you are building a true turbo-NA like I did, all the "little things" are fully covered in my writeup and in even more detail in Project Tina.

It sounds, however, like you are building a "6 port TII" as you are using turbo intake manifolds. In that case, then your parts list will be exactly the same as doing a TII swap, minus the block of course.

That means:

-TII AFM, TID
-TII injectors, secondary fuel rail
-TII ECU, harness (or modify the NA harness)
-TII pressure sensor

-TII front cover, intake manifolds, turbo, exhaust manifold, downpipe, oil and water pipes, water pump housing, and maybe a few minor things I am forgetting

The S4 has one wastegate actuator, and one twin scroll actuator.

Why are you street porting the engine? If you are turbocharging the engine and planning to run the aux ports open, all that a street port will get you is a lack of low end torque. Low end already sucks with the aux ports open, there is no reason to enlarge the ports and make it worse. The 6 port block as MASSIVE port area compared to the 4 port block, even in stock form.

Just buy a J-spec TII engine.

Yes.

 

Thank you for the post Aaron, yes you'r the motivation to allot of us 6 port guys, i almost went with an LS1 lol

 

this is my baby before i took her apart

 

In staying on topic I have question about the whole throwing the turbo **** on a N/A. Will the N370 be pissed off and throw codes if it doesnt see the boost solenoid?

 

There is a lot of good information on here, after long consideration, and considering the parts I already have to do a turbo setup for my S4. I figure I end up using all stock turbo parts.

-Series 4 Turbocharger (will modify by BNR)
-Series 4 Turbo Manifold
-Series 4 Turbo 2 N332 ECU (RTEK 2.1 modification to be done)
-Series 4 Turbo 2 AFM

I might as well use the Intake manifold, injectors, intercooler and piping from the turbo 2, I believe this will be the easier route.

 

seriously if you dont have the turbo get the s5.

and im not sure why everyone seems to think you mod the na harness. it works just fine the way it is.
and Mr Cake the turbo harness is more complicated to use than the na harness but you dont know about this since you are a haltech guy.

 

I already have an S4 turbocharger, got it for a really good price. It's something I don't mind, I'm sorta a purist, I like to stick with what the Series 4 came with, so I'm using Series 4 parts, but they are going to be modified series 4 parts, so if I make over 200HP to the wheels, I'll be happy.

 

Turbo and NA harness are almost exactly the same. There is one one or two wires (uh, knock sensor, twin scroll solenoid) that is additional. The pinouts at the ECU are the same.

 

Ok, I can understand the knock sensor, but I thought the twin scroll solenoid was actuated by vacuum.

 

refering to your choice in parts. s4 turbo isn't to bad some people think it flows better just get the wastegate ported. hands down the s5 intake mani is better flow wise. but a few things u might wanna get. turbo boost sensor, turbo afm, if u do go with a s5 intake use all ur sensors. i respect the wanna stay s4 thing its a s4 pride thing. also down the road i would upgrade ur drive train. tranny, driveshaft, rearend. the n/a tranny will give out at some point.

 

they may be the same at the ecu but go ahead and throw a turbo harness in a non turbo chassis. its aint gunna work. there are wires that hook up to the dash harness that are switched and give you issues

 

LOL, yeah funny thing about that drivetrain thing, the Coupe I acquired already had a T2 drivetrain swap done to it, all I need to do is Turbocharge it.

Also is there any difference between the S5 turbo intake and the S4 turbo intake.

And an after thought, I thought I'd ask if there were any bolt on aftermarket top mount intercoolers?

 

You really don't even have to bother sending the turbo out to BNR if all you want is just above 200HP at the wheels. The stock S4 TII turbo will do a bit over 250HP at the wheels without too much trouble on the NA block.

The actuator is vacuum operated, but vacuum to the actuator is controlled by a solenoid.

As I said, there are only a few minor changes needed to use an S4 NA wiring harness on an S4 TII ECU. Off the top of my head: knock sensor wire, twin scroll wire, and alternator field/warning wires. Not exactly a great difference.

 

So you telling me, at stock boost levels, I'm already looking at 250 HP, wow, that is an added bonus for me. The reason I was going to get the wastegate ported is that if I recall correctly, BNR provides that along with the basic rebuild package, although I could be mistaken. Not to mention this would prevent certain undesirable problems that come with the stock wastegate, which if I remember correctly is boost creep, which is something I do not want to happen, so basically it's a preventative measure to keep from killing the engine.

On the the Solenoid, does anyone have a picture of the setup and how everything is essentially hooked up, I'd like to keep the twin scroll, but if I have to, I'll ditch it, but from what I've heard it will increase turbo lag or something.

 

That 250HP or so would come at around 12 PSI, so at the 8-10 PSI you are wanting to run, you're probably going to be around 200-220HP depending on your tune.

If you are running the turbo intake manifold on the 6 port block, then your low end will already be lacking so I honestly don't know if the twin scroll matters much. But I know there is a good diagram in the FSM. I think it is as simple as just connecting the solenoid to the correct port in the ECU, then plumbing the solenoid in line with the actuator and a good vacuum/boost source.

Note you can port the wastegate yourself if you have a die grinder/Dremel and a welder.

 

So 12 lbs of boost is what is required for 250, how much would 12 lbs affect durability of a 6 port engine?

Can anyone comment on the twin scroll on if it will affect low end when doing a 6 port TII? Am I better off plugging it up?

I'll check my service manual, I had forgotten about it.

Yeah I know I could do it myself, theoretically, but I don't want to chance screwing up a good turbo.