OBDII Scanner Reading

[Fred Swanson]

What are your manifold press. readings from your OBDII scanner when under load?

[Fred Swanson]

Another question......manifold pressure isn't the same as boost is it? The solus scanner (Snap-On) doesn't read actual boost.

[jesilvas]

Should be the same. The MAP sensor is the Manifold Absolute Pressure sensor. So boost.

[wsigo]

Idle the truck. The MAP reading at idle will be your baseline. Anything over that is positive pressure IE: boost. So, you won't get the same reading from truck to truck.

Lots of things will make this different- truck, altitude, tune, how much the foot weighs, how much the truck weighs, pretty much everything.

[Fred Swanson]

I am getting up to 27 psi under acceleration from the MAP psi reading and up to 14psi on the mangaugeprs reading under acceleration if MAP is boost should it read 11-14 at idle? Thanks, Fred

[wsigo]

11-14 at idle yes, depending on your elevation. The higher you are from sea level, the lower the base line will be. So, you know your base line, you know your peak. Subtract base from peak and you have net boost.

[Fred Swanson]

Originally Posted by wsigo

11-14 at idle yes, depending on your elevation. The higher you are from sea level, the lower the base line will be. So, you know your base line, you know your peak. Subtract base from peak and you have net boost.

So I am around 16psi of boost?....I am putting a new compressor wheel in it soon, the existing wheel is a bit rough on the edges....hope this makes some change, Thanks, Fred

[NCHornet]

and 16lbs is about all you will see from a stock truck. Please fill out your signature so we know what all has been done to your truck.

[Fred Swanson]

Ok Thanks for the replies, I am changing the comp. wheel as the existing one is a little rough on the edges, don't know if that will change boost or not but it's getting changed, tried to do my signature.....see what happens, Fred