FPR's

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When upgrading to a K04 do you need a 5 bar FPR cos an the American forums they say you need either a 5 bar FPR or bigger injectors.

Cheers
 
I have not had my FPR changed and also have no idea what it is.
 
Not necessarily, but if you change the FPR you'll have to change the mapping otherwise you'll overfuel.
Also worth considering is if your fuel pump is man enough on certain upgrades, you might have good enough Fuel Pressure but you may not have a pump that can sustain flow on certain big turbo upgrades.
 
depends what your mapper says, you should have a remap when changing the turbo to make sure your not running lean (unless you have your own wideband lambda gauge)

you will only need bigger FPR or injectors if the mapper cant get enough fuel to make a good air fuel mix from the standard components, just changing the FRP/injectors could in turn lead you to running rich and have poor fuel economy
 
[ QUOTE ]
I have not had my FPR changed and also have no idea what it is.

[/ QUOTE ]

Fuel Pressure Regulator.

If you are running more fuel presssure then more fuel will be injetced into the cylinders for the same injector opening time compared to OEM...... I think /ubbthreads/images/graemlins/angel.gif
 
correct...

its all a bit of a balancing act...

fp / larger injectors / higher flow fuel pump etc etc etc
 
5 bar is a bit heavy for a k04, i think s3/tt use 4 bar and different injectors iirc and k03 3 bar, not sure about k03s, check with the mappers at star where you had it done, they can always bolt it on when they map

an A/f meter will tell you whether you're running lean or rich, if your running lean you will damage your engine, slot on a bigger fpr and it should sort out that problem, if there.
 
Star said a 4 bar would be fine but all the kits like apr etc come with 5 bar ones i just wondered if i would get more power if i had my car mappe with one.

Cheers
 
just interested in what size injectors people are running..

I have been doing loads of research into the injector sizes and have come up with soooooo many results it not real

thoughts please.

Andy
 
Soupie,

If your car is Quattro then you have a 4Bar FPR fitted already /ubbthreads/images/graemlins/smile.gif

For a K04 upgrade that will be more than enough, you just have to carefully select your injector size for the power you require.

I think it's safe to say that you won't get big power from a K04 anyway, that topic has been covered many many times on the forum and those that DO have in the region of the high 200's BHP are running the turbo at very high boost and to within an inch of it's little life!

Either way, if you want more power and you want the most from the turbo and for the car to drive properly, you need to have the car remapped for the K04, it's not just a simple matter of bolting it on and hoping for the best! At the end of the day the turbo is shifting more air than the smaller K03s and will need the map adjusted to correct fueling accordingly.

As far as injector size is concerned, I really don't know what size the standard ones are on our cars (I THINK it's roughly 220cc, not sure) but again, I think it's safe to say they are pretty small.

You don't HAVE to change them for more power because whoever maps the car will get more power from it with the K04 than they will with the K03, obviously. You MAY get more if you use bigger injectors but you won't know that until you put them in and try mapping it with them in there.

Best of luck buddy.

T
 
Yeah thanks folks, with the K04 fitted i would say that my car is a hell of a lot faster than i predicted it would be.

Everyone who i have taken for a spin has noticed quite a difference as well.

I can not wait till i get it all setup should be even quicker and give me piece of mind that all is well!!

Cheers
 
So you've changed the turbo but haven't remapped it yet? Or have I missed something?
 

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