Well i went to the tracks last night. And i have brand new tires. my best time ever was 15.4 and now i cant even run faster than 16.2. I'm also trapping 6 mph slower than i should be. does anybody have any solutions why this is happening to me? I'm launching good, good shifts. Any ideas?

 

were the tires the same size? and how worn were your old ones?
what I am thinking is maybe a difference in circumfrence.
also wondering if you were getting wheel spin.it takes tires a couple of heat cycles to really come in sometimes.

 

what do you consider...."good"?

 

same size tires (they are yokahama YK520, so they are pretty good, imo) and i can shift so please dont blame that. if i ran a 15.4 my shifting did not get worse.

I might also add that I just hit 120k miles. So maybe i need to change a few parts to make a difference thats NOT a problem yet?? so tires are barely used (3,xxx miles on them), i have a good clutch, i can chirp 2nd no problem. im not sure what could be making me 1/2 second slower and 5-6 mph difference...

 

well for me the biggest difference that i noticed was when I lost weight!!! Not tryin to say that your a big guy or anything, so hopefully you wont get offended, but 20 pounds is a hell of a difference.

how many times did you run?
It could be a number of things tires/inflation, heat/weather (im in va so right now the humidity is playing a really big factor even with just daily driving), wheel spin )like alset2 mentioned( , gas. I would have to say in order to get a more accurate feel the next time you head out try and record from inside the car and outside.

hope this helps alittle, but than again the post was still alittle vague, we aren't in the car with you so.....can't really give you a definete you know!!

 

Hmm, maybe problems with the car. Is your airfilter dirty? Bad gas? Knock sensor code?

If it has been a while since your last run at the track maybe even something such as your throttle cable. At 173,000 miles my throttle cable I found was misadjusted and pedal to the floor did not actually translate to wide open throttle at the throttle body.

 

Thanks for the advice guys, its possible weather is doing alot to me? when i ran my 15.4 it was in lower 70 degree weather. now im running in mid 80 degree weather.

And i only weigh 145, nothing more, nothing less. it changes maybe 3-4 lbs. but always evens back out to about 145.

 

Full tune up .... First clean the throttle body, iacv, change the spark plugs, change airfilter, and check for codes. I think your not hooking up though what was your 60'? Could also b a clogged cat.

 

im up to date on my maintaince. and suprisingly when i ran my 16.2 i had a 2.3 60', which is my best ever.

 

if the tires were very worn on your fast runs that is alot of rotational weight that the car has now with the new tires...new tires weigh alot more than worn out tires...makes a big difference.

keep that in mind too.

 

I wouldn't be surprised if the temperature had something to do with it too. I usually can feel a loss of power even in daily driving if the temp is 80+.


BTW, did you run with a full tank of gas? 18 gallons of gas has got to be well over 100lb's

 

i stay just under 1/2 a tank when i go race at the tracks, i always put supreme. Maybe temperature is just pulling alot of timing...

 

110.7 pounds, about 1/10th in the quarter.

 

yeah 100 lbs. isnt that much of a difference...