NOS and Audi FSI.... has anyone done it?

B6/7 S4/RS4
#1

Wondering if anyone has successfully added a NOS kit to an Audi FSI car (preferably non-FI).

I know that JHM has the kit for the B6/B7 S4, but that one won’t work on the FSI engines.

I am interested in a possible application for the 5.2 S6 engine, but figured there would be more chance of a response from someone in this section possibly adding it to their RS4.

Z06psi suggested a dual 25 dry shot to each of the dual airboxes on the S6. Somehow, I don’t think it would be quite that simple, but I have no experience with NOS kits. I would guess that there would have to be modifications made to the fuel injectors, plugs, dual ECU tunes (yes, the car has two ECUs), and probably other stuff, but would like to hear from any experts what they think would have to be considered to add a 25 or 50 shot to each side.

Would an aftermarket controller be necessary, or would the ECUs handle everything. I am looking for something completely safe that will work with the other bolt-on mods I am having done.

#2

duud40

#3

Thanks B!

Found this with your info

http://forum.rs246.com/viewtopic.php?p=400225

Single nozzle ,progressive pulsed delivery. 25 hp jets for starters. System should flow enough for 100 ish hp.
Wizards of Nos system .

http://www.audizine.com/forum/showthread.php/388469-Pics-of-my-rs4-the-nitrous-kit-awe-exhaust-and-a-short-vid

The tune looks/sounds like its really off. If you are running at 10.5:1…that’s really rich for an NA car. Even to be safe with the nitrous you should be running 12:1 to 12.5:1. Definitely leaving some power on the table.
Thanks !

The tune is actually the best possible outcome from what I had to work with (local fuel,temperature etc. ) .
Afr is 10.5 because I did not have enough pressure in the bottle. 125hp jets really go through the magic juice pretty quick.
The nitrous system provides fuel and nitrous for 125 hp if you have enough fuel and nitrous pressure. If nitrous pressure drops, the delivery of nitrous drops so youre left with too much fuel , ergo the rich condition. The car does need tweaking but its not the tune that needs work . I need bigger bottles and bottle heaters so that the nitrous supply stays stable.
The nitrous , when running in good conditions (nitrous pressure stable at required level) runs 12.5:1 with plugs looking very good.
The nitrous controller has active afr adjustment but I havent implemented it yet. No time ... That means that up to a certain level the nitrous controller will control fuel so you dont end up with 11:1 afr like I did in the vid.

This… Nice ride, but still needs tuning, we think…

From the look/sounds of the video, that is…
Again, it does need tweaking :smiley: . The ecu file is ok. Tested and re-tested. Provides the best real-world results .
At the end of the vid one of my coils had gone bust. Can you hear it ? Burpy sound at the end of the vid. Scared me !

Sounds like he never really got it working 100% with the 125 shot

#4

I believe duud and the one other guy who tried to do the nitrous ended up very poorly.

He was wrong about the nitrous keeping the car at 10.x AFR I can add all kinds of nitrous to the car unless the car is going into protection mode the car will never be that far out. Looks like he never got the kit or the ecu to cooperate.

With a v10 I would be very very careful with any plans to use nitrous without getting a plate system. With that many cylinders it would be too easy to have dry cylinders where some cylinders get more nitrous then others.

#5

I would love a plate system like the JHM S4 kit. I think when I asked CountVohn about it before he said it wouldn’t work with the FSI engines, but maybe I misunderstood. Ill ask him for more details next time I talk to him.

#6

That’s actually not true .

The kit ran fine , as far as I know the next owner had gearbox issues . Never engine issues .
The kit was a single nozzle system and my investment was in safeguards . It had fuel pressure sensors and nitrous pressure sensors and the system would cut off if pressure readings were out of the window .
I’m having difficulties replying from my phone for some reason . I’ll share my findings from a laptop shortly.

#7

Thanks duud! First hand experience was exactly what I was hoping to hear.

#8

Installed tapatalk . The app looks great .
So , nitrous and the rs4 worked great for me .
It was a time for experimentation and while working on the hardware we also tried quite a lot of ecu tunes too .
I installed a progressive nitrous controller from wizard of nos . The name is kind of funny but their products are pretty good . The controller was hardwired in the cars wiring loom . There were quite a lot of safeguards : throttle butterfly sensor , throttle pedal sensor , fuel pressure sensor ( low pressure) , nitrous pressure . The kit had a delay for nitrous and a time ramp up (as opposed to rpm ramp up) .

I started with 25 hp jets and I couldn’t really feel anything .
Then I went for 50 hp and I thought I would add an extra layer of safety so while on s mode and full throttle , the target afr was set to 10.5 . That may have sacrificed a few hp (although not as much as you might think) but gave me some perceived safety .
The setup was kind of mundane to be honest . There were no special parts or inventions . A line from the trunk to the engine bay for nitrous and a t piece in the fuel line before the stainless lines in the engine bay . Those both went into solenoids which were hidden in the compartment where the wiper motors and ecus are . Then you got two lines that went into the nozzle that was plugged in the rubber throttle elbow before the throttle body .

I’ll look for some pictures . they might be on photobucket and my account is the same duud40 . Have a look .

The stock ecus were unexpectedly friendly to nitrous but spark plugs and coils were less so . Changed to bkr8eix and set spacing (cant remember size) as well as new plugs and that was that .

I remember that one time I forgot ( lol ) to connect the electrical connection to the fuel solenoid . I had 75 hp or 100hp nitrous jets and made a run and logged some vag com stats . Bottom line is : the ecu compensated the extra fuel . I was then very happy to have set target afr richer .

One more thing to mention : the lines were not braided , they were nylon lines that had a small inside diameter . That meant restriction but also meant small interior volume . When I went over 100 hp I added a second nitrous line to be able to supply enough of it .

Overall I had fun and the car behaved very well (with nitrous at least ) . Went for a bigger bottle that I never used (20kg vs 15 lbs ) . At the highest setting which was 150hp the manifold would freeze over and turn white :slight_smile: cool for wowing friends .
I was expecting a fast and furious type of reaction but the result was always silky smooth . Small internal volume , progressive time ramp up and a really good intake manifold design made the system very easy to use .
At the time I really sucked at videos and only managed some crap vids .

I would describe it as opening the throttle more . Like in off nitrous mode the throttle goes to 75% and when on nitrous it goes to 100% , not like turbo , not like a supercharger , just silky smooth 25-30% more power .

Let me know if you need anything else .

#9

Thanks for the writeup!

I am a complete novice when it comes to this stuff, but I am wondering how the system you had would safeguard against the situation Justin mentioned where the NOS distribution is uneven across the different cylinders. Was it just by overcompensating by setting the AFR at 10.5:1?

I guess that would work, but I am not sure I would consider that a permanent solution.

Anyway, Ill wait for others to comment who are more knowledgeable on the subject.

#10

Nitrous distribution becomes a problem with over 25-30% of n/a engine power on a single nozzle . The best I can say is that I visually inspected plugs after wot runs and all looked well . Dunno about sustained (over a minute) nitrous runs . I kept them short (under 40 sec) and didn’t have problems .
The oem intake manifold when ported offers a pretty even distribution .

#11

Duud40 that wasn’t meant to be a stab at what you did or the kit I just remember us talking and you saying to do it right it was very expensive and the over all results were ok but not great. Mundane as you just said. Over all our PMs on EA I remember you said it worked but you weren’t happy with it and it would take more time and work to get it where you would want it.

#12

This except I wouldn’t go as far as 25% but when you consider the spread of intake and the difference between a v8 and a v10 there is even more concern.

Stock the cars seem to always have lower compression reading on the back cylinders. You also see plug differences there as well. . I would have to assume that this in part due to different distribution

#13

It’s all good man :slight_smile: .
Yeah I remember everything being expensive on that damn car .
I remember seeing a signature that described the way I felt about the rs4 very well .
the rs4 is just like a hot stripper , I keep throwing money at it and expect it to give me the ride of my life .

Every single nut and bolt in the nitrous system was expensive . The fact that I had to pay 30% tax and transport and it translated into the fact that everything was expensive .

But yeah you’re right , the system worked well from a technical point of view , it was correct . It wasn’t however the buzz I was expecting . You would probably need 200-250hp to keep up with tuned 997…1 turbos . I never got there though :slight_smile:

#14

Yeah man you definitely put in good money and time. You did it the right way and added the right parts. You were very progressive and really pushing the envelope with lots of sruff back then. When you said it wasn’t everything you wanted and wouldn’t really do it again. I make sure to pass that in to others. The way I look at it. When guys like you test something and really do it right I try to keep that work alive by making sure to let others know.

#15

Well that has changed , with time , I guess . Think about it , I was 20 something , I’m 27 now , I live in Romania which was barely in the EU at the time , had seen nitrous kits in pictures only and was elbows deep rednecking performance out of the rs4 b7 . It was eating up all my money and a good portion of my time . Thinking about it , it was probably a dumb thing to do . But I had fun , I learned a lot , I met (virtually) all of you guys and a lot of other nice real people .

And yes , I would like to keep it alive .
Happy 2015 ! :))

#16

Thanks for the kind words .

You guys seen the rs4 turbo thread on az ?

#17

Thanks again for your info guys

Ill take a look for the turbo RS4 on AZ. Sounds interesting :slight_smile:

Happy New Year !!!

#18

You can also look into the Nitrous kits for GM LS2 engines that use a plate between the throttle body and manifold. Those plates fit in an RS4 since they use the same throttle body.

#19

Direct port is the best option for these cars…any car really.

If you read… Duud is mentioning nitrous distribution as a problem. If you spray into a TB plate there is no guarantee each cylinder will get an even amount of nitrous and this could cause a ton of problems.

#20

Actually there is a guarantee the distribution will NOT be equal :slight_smile:
It might be just enough not to cause problems .
Depends on how much you use it for during a run . I doubt there is anywhere you can go to use it longer than 35-45 seconds at a time .