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Went to the track this weekend for the first time since converting to speed density and I noticed some issues with the high ambient temperatures. Track conditions were roughly 90* F. Within a few minutes after arriving to the track, since I drove the car and didn't trailer it, I hit the staging lane ready to make my first pass. IAT leading up to my first run was low to mid 80* F. First run shocked me, since it was my first pass on the new turbo while using LC for the first time as well. Didn't hot lap the car, as I knew heat soak was inevitable, and I also don't have the best clutch for drag. But as the evening went on, the car got slower and slower, even though launches, 60fts and shifts were consistent. My IAT's were heat soaking from the engine bay while sitting with the car off for an extended period of time. My IAT sensor is placed on the cold side intercooler pipe, roughly 5" from the throttle. Other than letting the car cool to complete ambient temperature or keeping an ice pack on or around the sensor, how do you combat IAT heatsoak, since the IAT readings will inherently determine WOT AFR?
I have drag'd my 350z a few times. Nothing major but I would open my hood to release heat while in the staging lanes and I took a spray bottle of water and a spray on my plenum, intake, supercharger and a few on the radiator to dissipate heat while I was waiting. I also just let the car idle for 5-10 minutes after my pass to circulate coolant and oil.
It's tough drag racing with very high ambient temperatures. One trick that I used to do when I ran an air-to-air IC was to use a garden weed sprayer to spray water onto the intercooler core before a pass. You need to be careful how much water you load the core up with becuase if it drips on the track you will be politely asked to leave.
This technique means that after the burnout the water mist evaporates rather than heat soaking your intercooler core. This means when you are ready for the pass it's like starting with a fresh, cool intercooler.
With all of this in mind though, heat soak really should only be an issue when you are in the staging lanes. With the amount of airflow you would be seeing at WOT, any heat soak should be well and truly eliminated by the 60' mark. If you're seeing high IAT in your logging for the entire length of the track it's possible your IC is not as effective as it could be or your turbo is operating outside its efficiency.