Hey guys, I noticed today that under boost my pressure reading changes from - to +. It went up to +0.05, and the measurement changes. Anyone know what that means? Is it sensing boost?

 

yeah, forced induction.

 

That just made my day..... OMG

 

Should've expected such replies. Anyway, to better ask my question, what does 0.05 mean? What does it translate to in terms of reading boost?

 

I keep a sheet like this handy in my car, the VAFC's readings are in kg/cm^2 not BAR.

VAFC Reading(kg/cm^2) = PSI
.035 = 0.5psi
.070 = 1.0psi
.105 = 1.5psi
.141 = 2.0psi
.176 = 2.5psi
.211 = 3.0psi
.246 = 3.5psi
.281 = 4.0psi
.316 = 4.5psi
.351 = 5.0psi
.387 = 5.5psi
.422 = 6.0psi
.457 = 6.5psi
.492 = 7.0psi
.527 = 7.5psi
.562 = 8.0psi
.597 = 8.5psi
.633 = 9.0psi
.668 = 9.5psi
.703 = 10.0psi
.773 = 11.0psi
.843 = 12.0psi
.914 = 13.0psi
.984 = 14.0psi
1.00 = 14.23psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beta13 &raquo;</TD></TR><TR><TD CLASS="quote">I keep a sheet like this handy in my car, the VAFC's readings are in kg/cm^2 not BAR.

VAFC Reading(kg/cm^2) = PSI
.035 = 0.5psi
.070 = 1.0psi
.105 = 1.5psi
.141 = 2.0psi
.176 = 2.5psi
.211 = 3.0psi
.246 = 3.5psi
.281 = 4.0psi
.316 = 4.5psi
.351 = 5.0psi
.387 = 5.5psi
.422 = 6.0psi
.457 = 6.5psi
.492 = 7.0psi
.527 = 7.5psi
.562 = 8.0psi
.597 = 8.5psi
.633 = 9.0psi
.668 = 9.5psi
.703 = 10.0psi
.773 = 11.0psi
.843 = 12.0psi
.914 = 13.0psi
.984 = 14.0psi
1.00 = 14.23psi</TD></TR></TABLE>

EXACTLY what I was looking for, thank you sir

 

Hmm, something may be wrong. It only read 0.05, unless I'm not remembering correctly...

 

its just slightly inacurate. my prelude would sometimes register a positive reading on the VAFC, and it was N/A

 

For those who
A quick way to translate kg/cm2 into psi, is to multiply it by 14.
That will give you a more than accurate enough reading.

ex: .5kg/cm2 * 14 = 7psi

I used to always use the calculator on my Nokia to figure out my boost while
driving. After a week of looking at it though you get used to it, so its pointless
to even convert it anymore.

 

You've never seen positive pressure under WOT from a NA car before?

Welcome to the 1960's big tuner secret.

 

Pic of my safc last year

 

maybe you have a good filter setup?

 

Stock map sensor correct?

 

Hmm, it's hard for me to get it to 0, let alone passed it....wtf? I have a turbo B20 at 6psi...