Ive got roughly 50-60 passeson a 04 a4 w/ 2.73 .......

Im normally between 13.5-13.7 at 102-103 mph all night in 80 degree weather....

On 16 Oct. I went again with a temp of 76 degrees (the lowest Ive ever ran in) Hawaii is usualy closer to 80 (even at night)...

But I did my worst ever.......

I ran a 13.7

another 13.7

then a 13.8

then a 14.0

then I let the car sit for an hour vrs the previous 20-30 minutes and still only ran a 13.8......


Now I realize that you can have good nights ad bad nights.....

If my best is only 13.5 then the two 13.7 and 13.8'sI ran are within a few tenths of my best.....

My 60 fts where all in the normal 2.1 range.....

The thing that scares me is my mph......

Why on the coolest night Ive ever ran my car when I was hoping for 13.4 at 103-104....

Im trapping 13.7-14.0 AT ONLY 100-101 MPH???????????

WHY WOULD MY MPH BE 1-2 MPH LOWER ON THE KOOLEST NIGHT EVER???


I just dont get it....I had this same stock car clocking 13.5 at 102.5 in 85 degree weather at the same track....I pulled a 13.5 at 103 mph two weeks ago in 79 degrees.....And a worst of 13.8 at 102 mph the same night

Shouldnt at 10 degrees kooler....I should be the same or bettr???


So far since the bad mph I went and got an oil change,,,,,,,

I ran out all the gas and refilled with the normal Chevron high octane..

I added 104 octane booster and a Chevron fuel injector cleaner....

I replaced the lightly dirty stock air filter ( only 4,300 miles on car) to a K and N air filter....

Is there anything else I should do????

Have any of you experienced anything similar with low mph....

What was responsible???

I was about to do a mild H/C job......Bu nowI dont want to do it till I find out if ...

The timer was jacked at the track....MY HUD was showing the normal 103mph before crosing the 1320...

I had some bad gas........

Or somthings wrong with my baby...

I realy appreciate ANY opinions on this....

 

Air Temp. is not the only thing that will affect your MPH. Its too late now but next time at the track, see if you can find someone with a TAG weather station. It will give you

TEMP
HUMIDITY
BAROMETER

And "Corrected Alt"

In my opinion the Barometer is as important as Temp... if the Barometer is low you WILL lose MPH & ET

Before you do anything to the car, go again & get the corrected Altitude & see what you run... then try it the following week & do the same.. See if you run quicker & better MPH when the "Corrected" Alt is lower.. I think you will...