Ok I have a quick question for all you guys that already know this.
How do you take what your scanner tells you on the map sensor and convert it over to PSI? My scaaner says Map ("HG) 75.3. This is what it maxes out to normal puilling is about 50. I know this isn't PSI by no means it's just I don't have the math formula to convert it over.

Thanks
Mark

 

You need to change the settings on your scanner! It took me awhile, but I found it on my snap on. Cant remember where the heck it was now though!

 

LOL yea I wish I could but this isn't a Snap-On but a Actron instead and you can't swap it over so I'll need to do the math myself

Mark

 

My laptop scan tool reads about the same peak value (74-75), but it's listed as "PSI". The minimum value I see is ~24psi at idle. I just assume it reads like that because there is boost fooling going on.

 

Could be. I don't use a uploader but I do use the Predator inline chip that does cheat on boost to the ECM. I'll remove it and see what it say without it.

Mark

Oh yea what laptop scan tools do you have and were did you get them from. I've allways wanted a program more because they will show allot more. Kind of scared to call Cummins and see what Insite costs.

 

I use the one from Autoenginuity.com. The one from Cummins is probably much more powerful though.

The difference between the two figures on mine is about 50 at WOT. My actual boost is around 40-43psi at that time. It's confusing because I would assume boost fooling would show you a lower number, not higher. I need to give them a call about that and also to find out why the "calculated load" figures seem off.

 

Thank, you
I'll check that out.

Mark

 

75.3"HG converts to 36.98 PSI @ 60 degrees. Here's a link to a unit calculator.

http://www.unitsconverter.net/

 

Ah, so it does make sense then. I usually see about 24 at idle and 75 at WOT. The scan tool lists it as "PSI" but it must really be "inHg" instead.

24 inHg = 11.8 psi
75 inHg = 36.8 psi
Difference = 25 psi

Looks like the boost fooler is showing the ECM a max boost of 25psi. I wish I could use the scan tool without a boost fooler, but I assume that would throw an overboost code.

Thanks for the link, dude!

 

vzdude

Thanks man is just what I was looking for.


Mark