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For better 1/4 mile runs, don't turn off your car!
Take it for whatever it's worth!
I went to E-town tonight for "test and tune" night and to practice launches, below are my observations.
Run 1, soon after I arrived and let the car cool down for about 20 minutes.
Runs 2, 3 and 4 back to back without cool-down time.
Runs 5 and 6, I shut the car off before the runs thinking they weren't going to let me run again.
Runs 7 and 8, both after run 6. But, at this point the staging lanes were getting busy (gap in time) and I was crawling through the staging lane while the engine is still running.
Run 9, I kept the car idling in the staging lane.
Oil temp at the start of runs 1-8 was ~215 and trans temp ~190. While the car was idling, before the last run (9), the oil temp dropped down to 206 and trans 179 https://i.imgur.com/GcXmQHr.jpg
Your quicker runs were most likely due to better DA (density altitude) as the night went on. As the track cools, air becomes denser, more oxygen, more fuel can be added, and more hp.
Also, look at your 60' time. How were you launching the car? Did you foot break it up to a certain rpm? Was there any wheel spin? I used to be a track addict, at etown and atco, and all those little things play a huge role in times.
Last edited by The Alchemist; Oct 14, 2017 at 07:48 AM.
This was with the JB1 piggyback right? Those times are pretty consistent, and you shaved at least a half second and added 4MPH over the stock trap speed.
Your quicker runs were most likely due to better DA (density altitude) as the night went on. As the track cools, air becomes denser, more oxygen, more fuel can be added, and more hp.
Also, look at your 60' time. How were you launching the car? Did you foot break it up to a certain rpm? Was there any wheel spin? I used to be a track addict, at etown and atco, and all those little things play a huge role in times.
The humidity actually went up at the end of the night from 70% to 90% Additionally, the weather didn't change between runs 1&2 or 4&5 or 6&7
My point is keeping the car running actually cools is down better than shutting the engine off and opening the hood. Another observation from previous track nights, launching at too high rpm, the trans freaks-out/heats and it doesn't shift as fast resulting in lower times.
Did you foot break it up to a certain rpm? Was there any wheel spin
Yes, foot break it up to a certain rpm and very little wheel-spin/chirp
Originally Posted by cenzo86
This was with the JB1 piggyback right? Those times are pretty consistent, and you shaved at least a half second and added 4MPH over the stock trap speed.
Correct JB1, below is my best time with it. Best bone stock was 12.8@107mph
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