hey fellas.... put a new head (aeb) and ko4 turbo on my a4.... it already has a chip by apr, fpr, dp, exhaust.... i recently bought some new bigger injectors and was wondering how much i should raise the fuel cc to.... stock is 240cc(@3bar)... i was running the ko3 at 4 bar (aprx. 277cc)... should i raise it about 100cc? to 380cc?....400cc?? ...

thanks

 

Bump....=)

 

Whatever your tune calls for

 

the car came with an APR program.... it had a ko3, and was boosting 16lbs of boost with stock fuel injectors at aprx 56psi....(that's maybe 250-280cc i'm guessing)... now that i have installed the ko4.... the turbo spools to 20lbs! i raised fuel pressure to 4bar (58.1 psi or close to that).... but i think it's running a bit lean.... without re-chipping, i'm just trying to figure out how much more CC i can run without going too rich.... i picked up some 400cc injectors and plan on testing them out around 380cc at first and adjusting as nessesary....

... monday i'll be messing around with all this.... i'll let everyone know how it goes...

 

well... it seems 400cc was too much... it would idle fine but once load was applied it would just bog down(flooded from fuel).... so i played with fuel pressure for a while til i found that at about 32psi = aprx 383cc it was running pretty damn good.... so i ended up getting some new injectors... 370cc and i'm running them at about 3 bar (43.5psi)

for all of those thinking about upgrading to the ko4 i say go for it! soo much more power than the ko3... the ko4 even spools up faster and earlier... great for even everyday driving.... looks like with the program i'm using it is still boosting 16lbs... the turbo spikes 20, but with this chip only holding 16... i need to get it reprogramed.... oh and i need a new clutch too LOL, my clutch is having a hard time not slipping a little with all the extra power. =)

 

Well, you did the right thing by starting rich first and working your way down. Running lean with a lot of boost is not good. Nice car btw.

 

31lb (315cc) injectors is what the giac k04 file is written for.

mods in sig.

 

thats for the pc16, the regular k04 file is for stock injectors

 

well.... i should probably turn down the fuel pressure then closer to 32-35psi.... 32psi would give me about 315cc...l but i think running that low of fuel pressure may cause the injector to not spray correctly.... any thoughts?
35 psi should be alright... and that would be about 330cc

 

so i talked to an APR dealer and they said they don't have a program for the AEB with KO4.... they only recomend using a 4bar regulator.... so i'm just going to keep my 370cc injectors spraying about 330cc and deal with my sorta crappy idle.... sounds like it misses every once in a while... but the car fly's!