guys with k04's and stock fueling

[lrg8683]

did you lower the boost when you got k04's put on or did you just leave it be? i'm assuming that k04's at 17 psi flow much more than k03's at 17 psi.. im thinking turning it down to 14-15 should be ok til i get fueling next month?

[updaboost]

17 psi w stock fueling is perfect.. I ran that setup for 9 months

[lrg8683]

17 psi w stock fueling is perfect.. I ran that setup for 9 months

but that's what im running my k03's at right now.. won't the extra air flow lean it out more?

[01 S4]

im running 18psi no problems at wot

[updaboost]

but that's what im running my k03's at right now.. won't the extra air flow lean it out more?

no but u should get a 5 bar fpr

[AudiSportB5S4]

I run 16 LBS of boost on VASTs file, its a rock solid file when i dynoed they did A/F and it was perfect except for one spot where it was slightly lean. If you want I can post that dyno chart and you can see the A/F, and my setup as updaboost was saying is stock fueling with a 5BAR FPR.

[lrg8683]

.. anyone else that can chime in? car won't be done til tommorow.

[AudiSportB5S4]

lol what else do you want to know? I have been 3- for 6 months. Buying fueling on Monday :) cant wait haha

[Daft]

.. anyone else that can chime in? car won't be done til tommorow.

The bottom line is that your stock fueling was ok with K03s at that boost setting. You will need more fuel to keep running you chip safely. That's where the 5bar FPR comes into play. Same injectors, more fuel pressure.

You really should do some logging first to see how the car is responding to this extra airflow and extra heat (if you have stock ICs). Then you can use Lemmiwinks to adjust timing or primary fuel to keep things safe if needed. Just be aware that not all chips work really well with K04s and tweaks. My APR chip didn't.

[lrg8683]

i guess ill have to find someone to log it.. the version of vagcom i had didn't work with vista so i'm kind of up a creek.. maybe ill just turn the boost down a few psi til i can log it. and i have and upgraded intercooler..i guess 15 psi will do, and ill see if the tech doing the install has vag to log it with.

[ThirdStrike]

My APR chip didn't.

the apr stage 2+ file works well with a little bit of tweaking.
op; get a 5bar or a inline fuel pump.. which is probably a good idea for full stage 3 anyways, the fuel pump i mean

[Daft]

the apr stage 2+ file works well with a little bit of tweaking.

When you say "works well", is this based on timing/CF logs? My stage I chip was lousy in the timing department. Peak timing was about 5-8 degrees by redline and it was all over the place in between.

[lrg8683]

i need the setup to work so the car runs ok.. im not trying t make power with this setup, talking to marc he said i'd need a 5 bar fpr if i wanted to make power with stock fueling.. i don't, i just want it to run fine until i go to NY in a couple weeks for a tune.

[ThirdStrike]

When you say "works well", is this based on timing/CF logs? My stage I chip was lousy in the timing department. Peak timing was about 5-8 degrees by redline and it was all over the place in between.

5-8 degree timing pulls arent too terribly bad..
how much boost was your setup running with the 2+ file?

[AudiSportB5S4]

so if you're only rocking it for a few weeks dont bother doing anything lol, you can run the same tune. just dont rock WOT too much or at all because you run the risk of overboosting and leaning out the motor. if you just drive normally for a bit until you go up for the fueling you'll be ok.

[lrg8683]

im gonna keep boost at like 15 until i can get fueling.. it was at 20!??! somehow when i first mashed the gas it ran up to 20 psi and i was liek uhhh.. nope. so i turned it down.. not enough though.. so ill turn it down some more tommorow.

[Daft]

5-8 degree timing pulls arent too terribly bad..
how much boost was your setup running with the 2+ file?

I think you're missing my point. My actual timing was 5-8 degrees. That's garbage.

Here's a quick graph of my VAG-COM logs from the APR 93 chip with my K04s and inlets:

[Cactus00S4]

im running giac's stg3- file with the 5bar fpr, and im spiking 20lbs and hold 18-19lbs

[YMJ]

i think im going this route..

i have a link that can get me K04's and hardware for 2200.. and i got a quote for installing @ 1660.. do i need to get a new tune? MAYBE i'll get JHM to tune it for me!

[lrg8683]

im just rocking 15 psi and not stomping on it too much it'll hold me over til i can a tune.

[Cole]

... i'm assuming that k04's at 17 psi flow much more than k03's at 17 psi...

17psi =17psi. [O_O]


The PSI is measured at the throttle body boot. SAME INLET as you had with K03. So the pressure going through the opening is the SAME as you had with K03.

The ONLY way 17psi would be MORE air flow is if the inlet were bigger, which it is NOT!!

Technically the K04 spools slighly slower than the K03 so it is not even reaching the boost as fast. So up to a point the K03 would actually require more fuel below that curve.


The only reason you will need more fueling is when you start to push higher boost beyond the K03s capability and the capability of the stock injectors.

[lrg8683]

yes but a gt35r at 17 psi should technically be flowing more air than a k03 at 17 psi right? but if the k04's are about the same then yes 17 psi is 17 psi.

[Cole]

No! What part of the scientific measurment of "pounds per square inch" are you missing?


A larger turbo can push more volume at a given pressure only if the volume of the tube its pushing it through is bigger! In this case the location the computer gets its measurement from has not changed! So no more air is going in!

To get the benefit of the bigger turbo the added ability to flow more air turn into more psi,psi quicker, and usually cooler!

[AudiSportB5S4]

how about a garret GT1 billion @ 17 psi lol. j/k :-p

[The_Jerbel]

A larger turbo can push more volume at a given pressure only if the volume of the tube its pushing it through is bigger! In this case the location the computer gets its measurement from has not changed! So no more air is going in!

To get the benefit of the bigger turbo the added ability to flow more air turn into more psi,psi quicker, and usually cooler!

The advantage of a larger turbo at equal psi, as stated above, is that they can hold that pressure all the way to redline, and the air is cooler because the turbo doesn't need to be spinning as fast to create that pressure.

[Cole]

The advantage of a larger turbo at equal psi, as stated above, is that they can hold that pressure all the way to redline, .

Read what you just wrote! Holding to redline is NOT equal PSI!! That is an INCREASE in PSI over the smaller turbo at a given RPM.

That is not what we are talking about here.

With the SAME software. There will be no increase. (it won't hold to redline until you change something other than JUST the turbo. ECU, MBC etc)

Yes, you are correct that with a CHANGE in software you can now take advantage of the ability to INCREASE the PSI over the rev range, more air flow, cooler per given level of compression etc. But that was not the question and that is where the confusion is.

[The_Jerbel]

Read what you just wrote! Holding to redline is NOT equal PSI!! That is an INCREASE in PSI over the smaller turbo at a given RPM.

That is not what we are talking about here.

With the SAME software. There will be no increase. (it won't hold to redline until you change something other than JUST the turbo. ECU, MBC etc)

Yes, you are correct that with a CHANGE in software you can now take advantage of the ability to INCREASE the PSI over the rev range, more air flow, cooler per given level of compression etc. But that was not the question and that is where the confusion is.

Maybe you need to re-read what I just wrote, AND settle down a little, un-twist your panties, and take a deep breath.
The two turbos have equal peak boost, but the bigger turbo will be able to hold that pressure all the way to redline. So the question many people have is "If the K04's and the GT's both peak at 25psi, then why does the GT put out more power? Well, because the GT can hold 25 to redline, and also it does it with cooler air because it spins and works less to provide that pressure.
The original question was "Isn't 17psi just 17psi no matter the turbo?" And the answer is no. I've already outlined the reasons. I'm done arguing about it with you.

[Cole]

Maybe you need to re-read what I just wrote, AND settle down a little, un-twist your panties, and take a deep breath.

You need to grow up or man up. Either be adult enough to not throw insults around or come say them to my face. You destroy all credibility when you resort to this.

The two turbos have equal peak boost, but the bigger turbo will be able to hold that pressure all the way to redline.

No one is disagreeing with this fact.

You are missing the point that without software changes or a mbc a bigger turbo will only do what the software tells it. So the boost will only peak at the same rpm and taper due to the software.

So PSI is equal for a given RPM until you change the controlling parts.

So the question many people have is "If the K04's and the GT's both peak at 25psi, then why does the GT put out more power? Well, because the GT can hold 25 to redline, and also it does it with cooler air because it spins and works less to provide that pressure.

Many people want to know where I get my dashing good looks from too but neither of these were the question by the original poster.

The GT puts out MORE total PSI becasue of it's ability to hold it. But both will act the same unless tuned for it. 25 psi is ALWAYS 25psi. What you are refering to is 25 psi at more rpm = more power. Which as stated before won't happen until you change software/mbc to make it do that.

The original question was "Isn't 17psi just 17psi no matter the turbo?" And the answer is no. I've already outlined the reasons.

No. The original question was about k04s putting more air out at 17 psi than k03s. Which is not true until other things are changed.

I'm done arguing about it with you.

[The_Jerbel]

I guess I'm not done after all.

You need to grow up or man up. Either be adult enough to not throw insults around or come say them to my face. You destroy all credibility when you resort to this.

I wasn't trying to insult you at all, in fact, I was trying to say that there is no need to get hostile when discussing these things. I got the impression from your last post that you were getting upset because of a mis-understanding. Sorry if you were offended.

You are missing the point that without software changes or a mbc a bigger turbo will only do what the software tells it. So the boost will only peak at the same rpm and taper due to the software.

So PSI is equal for a given RPM until you change the controlling parts.

In theory, I agree with this, except that the turbo isn't being controlled by the ECU or MBC or whatever is managing the system. The turbo is putting out a given amount of pressure depending on the size of the turbo and a few other variables. What is being controlled is the wastegate, aka how much of that boost is being released to the atmosphere.

The GT puts out MORE total PSI becasue of it's ability to hold it. But both will act the same unless tuned for it. 25 psi is ALWAYS 25psi. What you are refering to is 25 psi at more rpm = more power. Which as stated before won't happen until you change software/mbc to make it do that.

No, I'm not referring to the rpm's, I'm referring to the POWER the engine is putting out as a result of the turbo output. The reason that the bigger turbo will make more power at the SAME pressure, is because the air will be cooler. The pressure output on the turbos will be the same, given the same engine management.

No. The original question was about k04s putting more air out at 17 psi than k03s. Which is not true until other things are changed.

Again, a 17psi peak pressure is 17psi, but K04's will put out more total boost under the graph when analyzing the entire rpm spectrum, not just one given point at which the boost spikes. K04's put out a cooler 17psi than K03's do.

[Sniper512]

I would like to back Jerbel up K03s taper to 15psi at redline because they can't push anymore air than that. What he is saying is that with K04s you can get 20+psi to redline. So if you had your K03s spiking to 18psi and settling to 15psi at redline and then you installed K04s and left everything the same you would spike to 18psi and hold that pressure until redline. Fact is 18psi to redline will need more fuel than tapering to 15psi with K03s.