So, I picked a DataLogger a little while ago, it was at Sears, and It was on clearance.....anyhow, it just reads the OBDII port, and will record 5 user defined variables. One of them is "Intake Manifold Pressure", it records mine as around 28.3PSI at full tilt...I know that isn't my boost pressure straight up. However is that my boost plus atmospheric? meaing at full boost I am at around 13.9? Is that low? Maybe I wasn't at full boost, I am not sure what RPM range that occurs at....
Right now, I am logging MPH, RPM, Intake Manifold Pressure, Fuel Pressure and AirFlow Rate

Would there be more useful variables to log?
I have these at my disposal: Coolant Temp, Engine Load, Timing Advance, Short Term Fuel Trim (b1), " " (b2), Long Term Fuel Trim (b1), " " (b2), Fuel System Status, O2 sensor Voltage (B1, S1-S4) O2 Sensor Voltage (B2, S1-S4), and Battery Voltage.

I have no clue what the different O2 sensor voltage choices are all about....or the fuel trim....wtf is fuel trim? :-P


Jon

 

I'm using a similar device. It's read as the absolute manifold pressure. I have yet to find out how to read the numbers in terms of vacuum/pressure. I'd really like to know since my autometer gauge sucks ***.

 

Take the absolute pressure and subtract 14.7 (if it's in PSI). Absolute pressure is the manifold pressure plus the atmospheric pressure (14.7psi at sea level). Not sure how it applies to vacuum though.

 

Yeah, intake manifold pressure is what it says, the pressure in the intake manifold, which should be normal air pressure (1 atmosphere at sea level) plus boost.

 

Well, that is sorta cool that I have something to log that. I am not sure how that will help me exactly, but its neat nonetheless....it was only 35$ :-P

 

I want one.

 

No more at Sears.

However I have seen them for cheap on Ebay before. It is the DriveRight CarChip E/X, from Davis Instruments, out of Hayward, Ca.

 

Yeah i know. I looked all over sears website and didnt see any.

 

It is pretty neat though, good interface. It will calculate MPG, and price, if you enter it, per mile, etc.


This shows the normal plot that you can view, in which you can zoom, move it around, etc...
The dotted lines show braking and acceleration events, when you exceed user set levels measured in G-forces. Hard and Extreme events.... I had a few of each....lol


This shows the home screen, you can manage mulitple vehicles, calculate mileage, etc. It also shows top speeds, top acceleration rates, deceleration rates.


Jon

 

Just make sure you don't leave that in the smashed up wreck you created while driving like an a$$. Insurance co or popo might use it against you.

 

I wasn't driving like an *** :-P lol, I had to go out and test this logger out...I had just found the intake manifold pressure measurement....so, I live out on the edge of Davis...I drove around out on the backroads, at night...... :-D

 

that and I was testing my ABS....

it doesn't feel the same as any other that I have had with ABS, this seemed to lock up for a second before it started modulating, where as the Eclipse that I had would just pulse more at the pedal, but didn't lock up at all..... Is it supposed to lock up for a second, and then modulate? or do I need my brakes looked at?

 

I was talking about in the future. I don't care how you drive. Just try to leave as little evidence as you can.

Sport ABS is supposed to be less invasive. Could explain why you get a little lock up before ABS starts 'helping' you.