those datalogging boost, peep my logs...

does that dip look normal after each peak?

pull1.jpg


pull2.jpg


car has Cobb SRI and TurboXS hybrid valve...

i didn't concentrate TOO hard on the pulls because it was uber late and i would have been easy pickin's for a state trooper running around like that.
 
throttle position sensor i believe.

oops, i responded the the relative part, and not the TPS part because i thought that was obvious, sorry! (boobs)

yeah, its throttle position sensor, aka how far you have the pedal down. But like i said, usually, when you log TPS during some pulls, the TPS goes to the max value and flat lines during full throttle, goes to 0 if you shift and lift, and goes back to 100% for the next gear.

this log shows nothing like that with the purple line.
 
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does that dip look normal after each peak?

The dips are when you shift. So yes, they look normal. At least they look normal to me. That is pretty much what I see when I datalog. Somebody has already said this, but you need to log your A/F ratios.
 
That looks about right i see the same running stock boost(only because my CDFP is lost in never never land :'(...) only i spike a little higher with the Forge.
 
thanks guys.

i'll play around with the logging variables and get a/f on there....

i assume the factory o2 for these is a wideband nowadays and works on more of a span than the old 0 to 1v units?
 
re: relative TPS, i've yet to figure that out. there is no real rhyme or reason to it and it never comes close to 100%. during those boost plateaus, the TPS should be flatlined!

Thats because it the throttle plate not the pedal position. Since we have drive-by-wire BS, the ECU closes the trottle plate to limit boost in the first 2 gears. It also never opens the throttle plate all the way. With the new Mazda PIDs you can display pedal position which will indicate between 0 and 100%, but that is not what the throttle plate is doing.

Here is the description from the DH user guide

Sensors
TPS = Throttle Position Sensor in percent. This is the relative or “learned” throttle position, scaled from 0% -
100%. TPS will display a value of 0% at the "learned” closed-throttle position.
For example, if a 0 to 5.0 volt sensor is used (uses a 5.0 volt reference voltage), and the closed throttle position is a 1.0 volts,
TPS will display (1.0 – 1.0 / 5.0) = 0% at closed throttle and 30% at 2.5 volts. Because of the closed-throttle offset, wide
open throttle will usually indicate substantially less than 100%
.

Even the absolute throttle position will read less than 100% at WOT

Abs Thrt = Absolute Throttle Position in percent. Absolute throttle position (not “relative” or “learned” throttle
position) is displayed as a “normalized” value scaled from 0 to 100%. For example, if a 0 to 5.0 volt sensor is used
(uses a 5.0 volt reference voltage), and the closed throttle position is a 1.0 volts, Abs Thrt will display (1.0 / 5.0) = 20%
at closed throttle and 50% at 2.5 volts. Throttle position at idle will usually indicate greater than 0%, and throttle
position at wide open throttle will usually indicate less than 100
 

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