[Boosting89]

ok fellas..i have a 89 turbo with 550 injectors....255..walbro..VPC...as my tuning tool....how do i tune this thing with the vpc...and where should my fuel ratio guage read...lean ro rich..or in the middle..i dont know..i know the car is burning to rich..and can smell it when i am drive..i dont want to damage the engine by burning to rich...any idea what the vpc settings should be set on...
thanks

 

[lisiecki1]

14.7 is the perfect air/fuel ratio.......and I don't have a VPC so I can't help you on that, sorry...

 

[Zach90Turbo]

14.7 is too lean for a turbocharged vehicle in most situations. Different folks have different preferences as far as air/fuel ratios, 12 to 1 seems to be relatively popular. Any competent shop with a dyno can help with tuning, I'd try that before trying to tune it by an A/F gauge(which is most likely not accurate). The money you spend having somebody else tune it the first time is cheap, cheap insurance for your motor. Have fun!

 

[Justin]

so when you're at full boost or 100% throttle, it would be ideal to have a constant afr of 12:1(or close)?

 

[PM-Performance]

so when you're at full boost or 100% throttle, it would be ideal to have a constant afr of 12:1(or close)?

Yes. low 12's are ideal

 

[mullenc525]

vpc is of little use for tuning. it only scales the whole curve the same as adjusting fuel pressure or the afm screw does.

 

[spoolint78]

get a wideband and a fuel controller
ex. apexi safc, safc2, map ecu, standalone

and then start tuning the fuel curve.

you can't really tune with the vpc

 

[dbsupra]

you can't really tune with the vpc

not much, thats what the gcc was for.

14.7 under idle/cruise if fine. under boost or 75% throttle plus hi 11/ low 12.

low 12 is fine for street, but on the dyno hi 11's are the way to go. road/dyno loading is diff. if you tune for low 12's on the dyno thats closer to mid 12's on the street.

dave