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oztracktuning
January 24th, 2006, 08:32 PM
How much will variations in humidity effect the AFRs? When i logged mine today some cells that were getting close were a few % richer due to the humidity??

It was raining and misting at the time - once when i emerged from the rain on the freeway into what was much drier air the AFRs seemed to climb up closer to desired :Eyecrazy:

Is there a figure that can be put on it.

Steve
TAQuickness
January 24th, 2006, 11:42 PM
the difference is negligable. take a look at this calculator (http://wahiduddin.net/calc/calc_da_rh.htm).
Blacky
January 25th, 2006, 12:15 AM
The intake air temperature has a noticable effect on the AFR when running speed density. Is it possible the air temp changed when you went from rain/mist to drier conditions?

EFIlive's 03 custom operating system includes VE correction tables based on intake air temp.

Regards
Paul
GMPX
January 25th, 2006, 12:56 AM
Steve, forget the AFR's, what are the Qtec's like?, I wanted to get some of those myself, maybe just even to crawl through underground car parks and set off alarms!. I was also worried about our laws with regards to such things.
If you were logging, as Blacky suggested, it may be IAT related, check the IAT temps.

Cheers,
Ross
oztracktuning
January 25th, 2006, 11:05 AM
I will check the log regarding IAT - i have that table populated with 1% change every 10 degrees. With it as

I have 30 degrees set to 1.0 here are the numbers

0.969971
0.969971
0.969971
0.969971
0.969971
0.969971 at 20 deg
0.989990
1.000000 at 30 degrees IAT
1.010010
1.020019 at 40 deg
1.030029
1.040039
1.050049
1.060058
1.070068
1.080078
1.090088
1.100098
1.110107

ps. i just found the correction % for RH and its very small
oztracktuning
January 25th, 2006, 11:08 AM
QTECs are awesome. Large multi deck carparks can be fun - we often leave like a scene from a funny movie!!.

They are 5 seconds to quiet or loud. Only con on my setup is that there is little bit of sound leak through the valve, so on quiet it is pretty quiet but its a bit of a dirty quiet.

The car idles at 650-700rpm but with the cam and the 10.7:1 the idle can be felt as a sound even on quiet. On loud it sounds like a big block thumper - heaps of people that have heard it love it.