ET inconsistancy,am i missing something ?

just trying to see if i am missing anything in regards to the consistancy of my satellite.
in March i fitted 4.1 gears to the dana.nothing else has changed but i seem to get intermittant big swings in ET
i use a performaire predictor weather station but it seems to run high/slow to the car.
the worst is i have been getting not a hundredth or 2 under but up to nearly a tenth under
see the attached list of ET's with DA.the main difference between 09/03 and 09/24 was 60% humidity on 09/24 to 26% on 09/03
DA on 09/24 only moved between 1300 - 1800 all day.there was about 20 - 40 minutes between most runs.
should i set a new log up with only the quick runs to see what it says ?
4.10 gears fitted 08 March 2011
03/26 . ET 11.358 / DA 2094
03/26 ET 11.273 / DA 2189
03/26 ET 11.316 / DA 1971
03/26 ET 11.29 / DA 2136
06/08 ET 11.21 / DA 173
08/03 ET 11.244 / DA 1181
08/03 ET 11.189 / DA 949
08/03 ET 11.187 / DA 672
09/03 ET 11.211 / DA 1476
09/03 ET 11.142 / DA 1759
09/03 11.163 / DA 2086
09/24 ET 11.281 / DA 1475
09/24 ET 11.334 / DA 1656
09/24 ET 11.244 / DA 1307
09/24 ET 11.253 / DA 1380
09/24 ET 11.254 / DA 1540
09/24 ET 11.188 / DA 1300- 1400 = DIAL IN 11.23,solo pass
09/24 ET 11.198 / DA 1300-1400 = DIAL IN 11.18,red light
09/24 ET 11.187 / DA 1300-1400 ,grudge run

any thoughts
Tex

are your 60' changing too?

Tex, you need to delete the old runs for the box to be able to predict accuratley when the weather is changing from race to race is what i was told by Performaire when I talked to them earlier this year. I now delete all previous runs from the race before unless the weather conditions are real close(2 to 5 degrees F and 10% humidity and within .30 Barometric pressure) to being the same as the last race I was seeing inaccurate predictions with the old weather in the box, it became a lot more accurate when I started deleting the old runs B.P and humidity really play havoc on most N/A motors on gasoline, no matter how good the tune up is

With that many runs on my TAG it would be within .005
on the dial prediction ... are you changing ANYTHING
to the engine OR chassis on any of these runs... if
you change anything that log is void and you need to
start new

thanks guys.
no i am not changing a thing,i have seen little reason to do so.since changing the gears i started a new log - i did swap the front squirter a couple of months ago.thats it.
on saturday the 60 was 1.56's early,high 1.54's last 3 runs
Cab did they really say that for each meeting,dang,i thought they wanted a lot of different runs to get it right.that's what the manual said?
i will try that next time i'm out,may not be till Novembers Mopar Rumble unless i get time for a T&T

Tex

performaire predictor weather station?? what is that and is it really needed on an 11 teen car? Are any of those "hot lap" passes? If your 60 foot is the same and you are shifting the same my guess would be a hot engine. Or maybe a full gas tank vs. almost empty

Spend all your time making the 60's as consistent as possible first. The WHOLE run is set up of from your 60's. Then go on to the 330 times and see if you are hitting your 1-2 shifts accurately. If you are varying in 330, then find out why. Usually its incosistent shifting , REGARDLESS of whther or not you THINK you are hitting your shifts. A tattle tale tach has helped almost everyone that ever used it. Then watch the 330-660, your ET is all made up in the first eight mile. period. 1/8 th mile is EVERYTHING to do with your ET.

As already mentioned, is the car temp the same, tranny temp the same? Weight ( fuel?) the same.Do you stage the same, with the same procedure? The difference bewtween a full tank and half tank of gas WILL affect your ETs. Work on this stuff first. Dont worry about youe best pass, and your worst pass. Look for consistencies.

My friend has a 1966 Satellite it has a Hemi fiberglass hood with the scoop.That car ran way off like 11.76,12.03,12.09 thin a 11.82.We were working on it and we was running out of time and didn't put the hood on and it ran 11.71,11.73 but mostly 11.72s lol He never run it with that hood again.It could be little things like that. Bentwheel43

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Cab did they really say that for each meeting,dang,i thought they wanted a lot of different runs to get it right.that's what the manual said?
i will try that next time i'm out,may not be till Novembers Mopar Rumble unless i get time for a T&T

Tex

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Tex, what they said was to dump all the runs when I make a change to the car, motor or squirters I do a lot of testing on my car and run different tracks with severe elevation differences, 2500 FT above sea level 1/8 mile track to 180 ft above sea level 1/4 mile tracks I do keep diffeent data bases for each track but I'm dumping the runs when the weather changes a bunch, that doesn't seem to help the box get more accurate than .010 When I first started using it last year, different motor, slower, it was within .010, usually .008 or clsoer The bigger motor and testing has got it foul up, evidently My racing year is over so I will start a new data base next year, if I race much You need to work on the cars tune up to get it to not change as much , look at the jetting, timing and spark plug heat range, adjust it to get it consistent A rich tune up will change the ccars ET way more than a mixture that is dead on or a little lean don't get it to lean , That can and will hurt it, don't ask me how I know that