I've been boosting now for about 2 weeks. D16y8 Greddy Kit, 5 lbs. (via boost gauge), Stock block.

I decided to take down some numbers. The max reading on the VAFC reads .20 Kg/cm2. The boost gauge reads 5 lbs at full boost, and holds a steady -19 mmHg at idle. (Ultra-Lite Series).

I did a little reaserch and came up with the conversion formula to convert Kg/Cm2 to PSI which is Kg/Cm2 x 14.223 = PSI

Sooooo......I came up with this.....

.20 Kg/Cm2 x 14.223 = 2.8446 PSI

This does not make any sense to me, and it really bugs me because I have no idea what amount of boost is going into my engine. and furthermore I dont think im running 2.8 lbs of boost.

What should I be pulling on the boost gauge at idle. could I have my VAFC hooked up incorrectly.

any input would be greatly appreciated.

JOn




Modified by shadow103rd at 3:46 PM 5/30/2004

 

a discrepancy is normal between the afc and boost gauge, however it's usually not that much, in my experiences.

anyone care to share their input?

 

bump.....someone please help

 

bump.......this discrepancy really bothers me.....

JOn

 

bump with some new info.........

Jon

 

mine's off by a good margin too...10 psi = 0.55 kgcm2 and the map sensor reading never goes over .60 no matter how high i boost which is around 12-20 psi...

 

So then should I trust the VAFC or the boost gauge???

 

boost gauge...

 

Thanks for the replies.....

JOn

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jockobo &raquo;</TD></TR><TR><TD CLASS="quote">mine's off by a good margin too...10 psi = 0.55 kgcm2 and the map sensor reading never goes over .60 no matter how high i boost which is around 12-20 psi...</TD></TR></TABLE>
Your car is OBD-0 correct? The reason your vacf stops at .60, is because thats
close to the higest value your map sensor will read. Even if you boosted 30psi,
the map sensor can only read so high.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rioninja &raquo;</TD></TR><TR><TD CLASS="quote">
Your car is OBD-0 correct? The reason your vacf stops at .60, is because thats
close to the higest value your map sensor will read. Even if you boosted 30psi,
the map sensor can only read so high. </TD></TR></TABLE>

does it matter that im using a map sensor from a 96 civic? i tried the obd0 one and it read even lower than this one.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rioninja &raquo;</TD></TR><TR><TD CLASS="quote">
Your car is OBD-0 correct? The reason your vacf stops at .60, is because thats
close to the higest value your map sensor will read. Even if you boosted 30psi,
the map sensor can only read so high. </TD></TR></TABLE>

my vafc will read .64 at full boost, a little over 9psi.. do you have a missing link or check valve on the map sensor? if you do you will not get a correct reading on the vafc it will always read lower then it really is..

 

also, the autometer gauges have been known to be off a couple lbs sometimes (not good)

mike