The warmer weather has just broken here on the east coast. Temps are now in the 70's as opposed to the 40's and 50's we were seeing. For some reason my car feels slower. Does the outside temps really make that much of a difference? All my gauges are reading fine. The car seems to be running well. In fact I think i fixed the problem that was giving me error codes (no codes over the past 130mi.. was getting them every 40mi), so what gives? It seemed before I could easily break the tires loose in 2nd and 3rd. Today it felt like I couldn't break them loose in 2nd. I have an ECU reflash. Does the ECU adjust to "dumm down" the car if you are not driving it aggresively? This past week I have only used the car to go back and forth to work so I have not really gotten on it. Will this cause the car to adjust for milage? Is this all in my head?

 

The car feels slower because it is slower. There are 3 factors affecting horsepower:

temperature
humidity
barometric pressure.

Those numbers are important enough to post on time slips.

 

i wish i our tracks had that on the time slips cause my best times would even look better, they were all dont 75 degrees with 85-90 % humidity... hehehe

 

While dynos correct for these things(baro, temp, humidity) the racetrack cannot. A motor in January will make more power than in June(all things being equal) and the dyno correction factors will be different between these months but a dyno applies the correction factor to make these numbers comparible. A racetrack doesn't have these correction factors and that is why many people consider it to be the true test of horsepower. The guy at the tree can't "fluff" your ET. To answer your question, your car is probably slower now.

 

That Sux. I wasn't expecting that much of a drop off. I guess with the warmer temps and the rubber sticking better is what is doing it. It was fun almost sliding sideways in 2nd.

 

Gosh, davidv, can't you do better, reaction time-wise, than for your 14.76 et run?!? Just kidding, he he. One thousandth of a second reaction, whew! When you're hot, you're hot! Man it would be sweet to be able to do close to that every time, would it not?!? I won second place in trophy class last year and had 2 runs during eliminations with .003 reaction times. And another run at .09 reaction time. I had the race won in the final elimination but failed to tap the brakes and broke out by .002 secs. Because I just KNEW, ha, that the run was a little slower than my dial in – till I screwed it up that is. I had room to tap my brakes and still get to the finish line first, but nooooooo – I had to have a brain cramp instead. I snatched defeat right outta the jaws of victory! Eh, second place isn’t too bad. Note I do NOT usually have reaction times as good and as consistent as that day. Wish I did!

Yes, it is very true. Temperatures really do affect power and ETs. And humidity as well. The cooler denser air just makes more power. That is what makes bracket racing so tough. It is not just your car you have to think about, the weather is often going to change 20 or more degrees (my drag strip starts time trials at noon) from your first time trial till eliminations begin and keep changing after that if you don't get eliminated. And as you win, the time between subsequent rounds gets less and less and your engine has less cool down between rounds and that affects power. I have had the changes in temp during a given day show me down by 2 tenths of a second - which is approx. 20 hp loss due to warmer temps. It is a bummer, BUT... a BAD day racing is better than a GOOD at work! IMO.

Get yourself an oil cooler as this should help battle hot temps a bit.

I'm thinking of trying one of those aquamist systems for the intercooler with forced induction to cool things better. That is one way to combat the heat. Water injection helps but I've never done that. Guys also put bags of ice on the plenum between runs. I'm too lazy to do that, ha. Some guys spray nitrous oxide on the intercooler to cool during runs but I am afraid some of the nitrous may get into my intake and lean out my mixture. Running lean on a hot day with forced induction is BAD. I do spray down the intercooler with water from a hand held sprayer before a run but I don't know if that does any good or not. Makes you feel like you are doing something anyway, ha. It is called the placebo effect.

 

he ran a 14.076 not 14.76 but anyway.
your tires probably hold traction better also due to the warmer temp of ur tires now and reduced power. I have noticed the same things with my car lately as it progressivly got warmer. Oh well, time to start with more mods to compensate.

 

Maybe you have a few to many Big Mac N Fries at Mac D's

 

Nice reaction times.

 

Welcome to the club. It's been in the 70's for two months here in Florida.

I'm going to start practicing on some DR's this summer to hopefully hit some nice times next winter.

 

How did you fix those error codes?
Thx!

 

Thanks for the correction. I hate to loose 0.70 seconds.

 

 

When the humidity is 80 percent plus, the track is like-slip-and-slide. First gear is impossible. Second gear is difficult. You should be aware of the staging pad conditions before the run. Its not a deficit because your opponent has the same problems.

 

i see what ur saying, but right now the humidity isnt high, its just the temp that went up.
what r u trying to say about the staging pads though. When to do a burnout and when not??

 

and i havent seen anyone ice their intake manifold in a long time. i saw it on a lightning a couple years ago and thought it was stupid. Man how much ive learned!

 

maybe you gained some weight? haha j/k

 

Not exactly. I do not burn street tires. Unlike slicks, they are designed not to heat-up. I go around the water box, then do a quick chirp to throw off debris.

At the Christmas tree on a humid day, the track surface can be dangerously slippery. You will know it when you release the clutch. Just back off the gas a bit.

 

Reversed my secondary O2 sensors. I think they were on backwards. I swapped them on the down pipe and did an ecu reset. I have about 120 miles or so w/ no codes. I was getting them consistently every 40mi after an ecu reset. Some said it shouldn't make a difference BUT this also cured another member's ride with the same problem.

 

Oh yeah, I meant 14.076 sec. The Typo's my bad. (And 14.76 is not a good time so I should have been more careful.) My point was that reaction time.... .001 sec! Congrats again, davidv

Ha, isin't is funny I said that about his wonderful reaction time a couple of days ago and guess what? Yesterday, during a test and tune day at the drag strip, I had a .000 sec reaction time! I can't remember ever having had one before. I have had .001s (not many), .002s (not that many), and lots between there and .010 and so forth, but never a 000 sec. Not that I can remember anyway. And I realize that there is very much an element of luck with my 000, but it is fun anyway!

And I have had way too many redlights with -.01 ish sec screw ups. But lets not think about that, ha.

I'll post my 000 reaction time if anyone cares. It's not big deal, but since I'll probably never do it again, it is neat to me. I also had a 2.0 sixty foot time on that run which is pretty good for the worn stock tires and 17" wheels. I ran 14.1 something or another which is not bad as I am pure stock down to the air filter. On a cooler day last fall I ran 13.9s. Hoping for APS twin turbos within the next month or two and much better times.