I took my car to the quarter mile at bowling green kentucky expecting to run 12's. My last trip to a track was our local 1/8th, I ran a 8.11 at 86.8 mph with a 1.71 60'. The only change to the car are the tires, i now have 245'40's that have a 300 tread wear.

Today the best pass was a 8.58 at 83.2 1/8th with the quarter coming in at 13.25 at 106. My best 60' was 1.98. The car felt like i was hooking up but the clutch was smoking a little (its stock).

Now for my question, the night i ran the 8.11 it was 53 degree's out, today it was 84 degree's. Will this temp change cause the 4tenths and 3.6 mph? And what do you all think the car would have run would it have been in the 50's outside? any input will be appreciated.

On a side note my brothers STI picked up 4-5tenths and about 4-5 mph, he ran a 13.45 at 98.8, his car is totally stock except for a cone filter.

 

Temperature could definately effect your time by as much as .5 sec. that might not necessarily be what happened that night, but it's possible. Turbo cars are especially sensitive to weather. Heat, but more so humidity causes slower times. Colder air is more dense causing more boost with less work. Hot air is thinner making the turbo work harder to produce the same boost. That's the best way I can think of to explain it. If your brother's STi picked up time and you lost time, it was probably the driver, not the weather

 

It had rained earlier and the humidity was high.

 

Humidity and large temperature changes will affect ANY car, especially turbocharged cars. This can be most pronounced in MPH.

It's completely feasible that you lost that much MPH with a 30 degree temperature change and high humidity.

 

I believe the temp and humidity can play a significant role in power production or lack thereof, especially with the stock intercooler.

IMO, an aftermarket FMIC will help make the power more consistent during warmer days. I think the stock intercooler can disicipate heat real well, when the ambient temperature is very low, but when the ambient temp is higher it can't transfer heat as well. Just my thought on it.

Brian

 

of course heat can effect performance. watersprayer is for those hot hot days...

 

No doubt the weather had a sizeable effect on your times, but what about your stock clutch??

How many runs on it?

Mine is gone after 4 trips to the track and about 20-30 runs..