I went to Beech Bend Dragway on Sat. 11/6/10 knowing the air would be great... The plan was to get my totally stock O8 A6 car close to or in the 11's

I made 5 total passes and let my son make one... For the 1st 5 runs I had the shrould propped open and the factory air filter removed. for the last pass I replaced the filter and buttoned up the shrould...

#1- 60 ft 1.90 12.03 @ 118.97... all nannies on temp 43 DA -909

#2- 60 ft 1.879 12.06 @ 117.47 ... Comp mode temp 44 DA -761

#3- 60 ft 1.92 12.10 @ 117.45... all nannies on temp 45 DA 761 my son drove on this pass, he has 40 lbs on me...

#4- 60 ft 1.882 12.01 @ 116.26 all nannies off temp 45 DA -900 the best et

#5- 60 ft 1.91 12.08 @ 116.23 all nannies off Temp 46 DA -684 Car felt like it was spinning about the 30 ft mark...

Now for the interesting part. with the DA and temp rising I knew the 11's were out of reach. So I reinstalled the airfilter and closed up the shrould..

#6- 60 ft 1.899 12.20 @ 118.06 all nannies off Temp 47 DA -548


Go figure, highest temp and worst DA of the day and with the filter back in it runs the 2nd fastest mph of the day....


Some more info... I had the car weighed with 3/8 tank of fuel.. 3177 lbs... Its a 1LT with only chrome wheels as an option.

1/8 mile times were... 7.83, 7.87, 7.87, 7.81, 7.87, & 7.94

Video of the 118.97 run
http://www.youtube.com/watch?v=RZdMjzBM9o8

 

I just may try that to see if I can get her in the 11's

 

Great runs! But it's frustrating being so close to the 11's! I know, I had a really cold day a couple years ago here in Phoenix and I ran a couple of 12.03's at 118, then it started warming up and I knew it was only going to go slower. Again, great runs!

 

Next time out, try the filter in with the shroud propped. The filter reduces the turbulence on the high end and the propped shroud allows cold air more quickly at the start.

If you get similar DA, you'll see 11's.

 

great runs and that is the best color for the vette

 

what mods on the Z06 you were running up against?

 

not bad at all! those are interesting stats for sure esp. w. a totally stock car. also interesting re the advice to leave in the air filter. thanks!

 

I think that explains the variation in mph on my runs.... When driving the car through the pits with the filter removed there was plenty of surging and bucking... Didn't notice any of that going down the track....

 

Besides hedders and drag radials, I'm not sure...

 

I recall the computer takes fifteen minutes of general/typical driving to adjust to new air flows.
Could sway your results.
Not sure if WOT affects the learning time/ difference.
I like the filter in shroud open option.
Last run, and you mentioned weight, was x gallons less than first run. 13 pounds per gallon I believe. FWIW

 

Gas is About 6.1 lbs per gallon... I be surprised if you used even a 1/3 of a gallon per run...

 

gasoline weighs ~6-6.2 pounds/gallon. Four WOT runs might have burned up a gallon, but not more then two. That little weight savings on the fifth run wouldn't be noticeable. Old rule of thumb is 100 pounds equals .1 second in ET.

 

I better go on a diet

 

Good point Joe.... I left the house with 1/2 tank of gas, drove 100 miles to the track, was at 3/8 tank... Made 6 passes, was just below 1/4 tank.... Drove 100 miles home, low range warning came on just a few miles from home.. Total mpg's for the day per the DIC...24.4 mpg's

Gonna go fill up now with some non-ethanol 93 octane...

 

I hate to burst your bubble, but that's not really a good way to test the overall differences:

1) Whenever you change anything on the car affecting airflow (either incoming through the intake or outgoing through the exhaust) you need to retune it to make sure your WOT AFR is where it should be.

2) Getting the 2nd highest MPH on your final run was probably a result of having a slightly higher ET. Most people think that a better ET should also result in a higher MPH but that's usually not the case because being having your 1/4 mile run last longer gives the car more time to build up speed. Last year when I was trying to chase a 9 second timeslip I ended up cutting my highest trap speeds ever (a little over 141 MPH) but because of my drag radials almost being dead that day, my ETs were off by almost a tenth from the week prior.

3) You also need to take wheelspin into account as well as where the car was shifting. The A6 is notorious for short shifting if you don't get good traction off the line so what may have happened with the shroud being opened up is that you were making more power but getting less traction as a result.

With all of that said however, kudos to you for taking it to the track and running it hard!

 

I had a blast and even let my son make a pass... run #3.... and how does this darn multi quote thing work???