prodigymb

My previous best was a 11.66 @120 with 1.80 60'. I went to the track yesterday and got 4 runs in. I couldn't even break into 11s and my trap speeds were 113-114. On my best run I got a new personal best 60' of 1.78 and went 12.0@113.39

It was about 82-85 degrees and 95-100% humidity. Can the weather conditions impact the car by that much? Or should I start trouble shooting, if so where....

Mods..
Evosport Pullies (175mm)
Evosport Ceramic Coated Headers
Evosport Phenolic Spacers
AMG 80MM Throttle Body
LET DynoTune
K&N Air Filters
Custom Exhaust
Johnson CM30
Code3/Spearco Heat Exchanger

Exotic-metal55

Yes it can. Go back and calculate the DA on the day you ran the 11.66 and then compare to now. As a very general rule, you will lose .10 per 1000 feet of increase in DA.

Barometric pressue and temp are the largest HP robbers, then I would say humidity.

Once you have a general ET on your car, know your DA, then you can generally pre-calcualte what your car will run before you even go to the track. That way, you can go to the track and have a good idea if you will beat your last time.. Of course, this also means knowing your car, same race weight and no major changes to the car.

blackbenzz

What conditions were your previous best run in? Have you checked your intercooler pump to make sure its working? If you are running in bad conditions I recommend icing down the blower before a pass. If your pump is wired to always run with the ignition on I would let it cycle a few times with the ice on the charger. If you have an ice reservoir even better.

Juice1979

Yes it can.

Go to weatherunderground.com get the stats for yest at the time you ran and enter it here

http://www.modulardepot.com/?show=density

TMC M5

Forget the weather correction calculators, the ECU may pull the timing more aggressively. The DA correction calculators can not take that into account.

Tom

Exotic-metal55

Bottom line,, If you run in a worse DA than your best ET,,, then you will be highly prone to have a worse ET. Unless you add more HP!

Why does the ECU pull timing aggressivley?? Simple ,, he ran in Frickin horrid heat!! That is all part of a high DA, heat and engine management adjusting to heat..

If you do not watch the DA, then you will never have a baseline on your runs or cars power. You end up just guessing, wasting gas and tires. Then feeling bad/confussed about how your car ran..

prodigymb

i have to look up the conditions for my previous. i think the DA was around 300-500.

last night the car felt sloww

TMC M5

You missed what I am saying. You can run the numbers through a DA calculator and still come up "short" in figuring out your car's performance. For example you can plug it in a DA calculator and it could tell you that your 12.0 @ 113 should be a 11.8 @ 115 at sea level conditions. He could correct the 11.6 @ 120 to an 11.8 @ 118 at sea level. The difference is likely the ECU being much more aggressive in pulling the timing than any calculator is going to assume. I wasn't saying that DA calculators aren't helpful...just that they aren't going to capture the full story...especially on the trap speed (as the launch should not be affected as much).

Tom

prodigymb

i have to look up the conditions for my last run but i think da was around 300-500. i did not check anything yet. i gotta stop putting off getting a rear mounted reservoir

Juice1979

your better off waiting till November to run. Wait till its mid 30's out and the DA is around -2000 at atco, then run..you will shatter your record and wont be dissappointed at all.

Karlson

agree with rest of posts. Summer time is bad for turbo/supercharger cars. On my previous car I was doing 0.5 second slower in 1/4 times during summer

BenzoBoi

+1 I'm definitely waiting for cooler temps and better DA's. I'm aiming for a new PB and I know it's not gonna happen in this heat...

prodigymb

on a positive note i was testing an intake setup for 2 of the runs that gave me a a 114 and 115 mph traps.

.8-1.5mph higher then without it

mkonei

i knew i should have went last night. lets see some pics of the intake..

V12Godspeed

+1. Please share..lol...

bassn_07

You never know Sun, I wasn't expecting to beat my own PB at Sacramento in the warmer weather but I did. I think it's a great time to get out and practice and just get to know your car a little bit better. I've learned quite a bit on my last two outings and hopefully that will help me run better times during the cooler months. In other words....Get up here on Aug 7TH .

Prodigy, I just recently witnessed how DA affect our cars...it was ugly. On average it seems I lost a little more than a tenth and little over 2 mph per 1000 feet. The differenc in DA between my PB and Fontan was around 3000 feet. It was great to experience how DA affect our cars but I'm pretty sure I won't be doing that again. 105 degrees kills the brain after long periods of time .

bassn_07

Ahmad, How much do you really believe this helps? I only tried it once and it seems like that bag of ice didn't help cool my SC at all. I guess if this what all the supercars are running it would be worth another try.

prodigymb

soon

hooleyboy

I think it only helps to make a wet mess. It doesn't take long once you start your car for everything to get hot. People do it though, from blown Mustangs to Mercedes. Maybe it does work anything for a 10th i guess.

I use to run my IC pump when my car was off to keep things at a less then stupid hot temp. That back fired when Chiromikey had to jump start me in the staging lanes. wont be doing that again.

c32AMG-DTM

First reaction was to this comment, then I remembered that you have an IC pump that could drain someone's pool for them - guess that sucker draws some current, eh?

prodigymb

what pump do you have?

lightningfast7

where did you jump the IC pump? i was looking at doing this at the track since the track temps were 120+

loungn14

in the midwest on track days, its actually odd to see someone not doing this...

blackbenzz

It does help. Let it sit for a bit til the charger is cool and cycle the fluid using the intercooler pump. I put the ice bags in another bag to prevent a wet mess. I dont have an ice reservoir installed so this is as close as I get. Its been proven that the ice resrvoir works. Think about it, cooler IATs and less heat soak. I can hot lap the car and not lose mph but if I let it sit in the lanes it quickly gets heat soaked.

hooleyboy

I'm running a Jabsco Water Puppy as in IC pump. Its kinda loud but it flows like an SOB. My pump turns on when the key is in the AUX position.