Jack B
12-26-2013, 11:42 PM
I installed the oem air box that that had been insulated with tunnel wrap. About one month ago I posted the results of plotting the temperature of the intake tubes versus the car's IAT readings. That data was taken with the ambient at approximately 40 degrees F, today the air temps were approximately 32 degrees F. When the weather gets closer to 40 degrees I will repeat the original test.
The addition of the tunnel wrap dramatically changed the IAT relative to the temperature of the engine bay. This test was conducted in the same manner as the last test, the car was started in the garage, pulled outside and allowed to idle for 20 minutes. As we all have seen, the difference between ambient and the IAT are always 20, 30 or even forty degrees. This data is at idle, however, it is the transient response that we are worried about. When the car is at speed the ambient and IAT will close, however, in the staging line at the drag strip seems to be a problem.
As stated, I am going to run this test again when the outdoor temps get close to 40 degrees F so we can compare with the previous data. Keep in mind at idle the car's displayed ambient will read higher than true ambient at idle due to the heat soak of car itself and the air around the car. Again, the caveat is that there was a 10 degree difference in this test and the last test. However, that data was so dramatically different it should not alter the gains the insulation showed, in this test the temperature difference between IAT and ambient air temps was basically zero, not 20, 30 or 40 degrees. The IAT's were actually less than the car's displayed ambient temperature.
I had a scan tool hooked up to the car and I was monitoring both temperatures and STFT's. A sample of that screen will follow. I have also installed a wideband O2 sensor and will log the a/f to make sure the IAT was not fooled in the wrong way. The scan tool in the picture is actually made to install in a semi-permanent mode. It is called a Dashdaq and has the ability to both scan and log. You can also input an analog 0-5, that is how the wideband will be displayed and logged.
I fabricated a plate that will extend from the radiator down to the circular cross member. It will run parallel to the box and about an inch below the box. That will go on this week end. That will further reduce the both the convected and radiant heat gain on the air box. I will run some more test after that install.
201520162017
The addition of the tunnel wrap dramatically changed the IAT relative to the temperature of the engine bay. This test was conducted in the same manner as the last test, the car was started in the garage, pulled outside and allowed to idle for 20 minutes. As we all have seen, the difference between ambient and the IAT are always 20, 30 or even forty degrees. This data is at idle, however, it is the transient response that we are worried about. When the car is at speed the ambient and IAT will close, however, in the staging line at the drag strip seems to be a problem.
As stated, I am going to run this test again when the outdoor temps get close to 40 degrees F so we can compare with the previous data. Keep in mind at idle the car's displayed ambient will read higher than true ambient at idle due to the heat soak of car itself and the air around the car. Again, the caveat is that there was a 10 degree difference in this test and the last test. However, that data was so dramatically different it should not alter the gains the insulation showed, in this test the temperature difference between IAT and ambient air temps was basically zero, not 20, 30 or 40 degrees. The IAT's were actually less than the car's displayed ambient temperature.
I had a scan tool hooked up to the car and I was monitoring both temperatures and STFT's. A sample of that screen will follow. I have also installed a wideband O2 sensor and will log the a/f to make sure the IAT was not fooled in the wrong way. The scan tool in the picture is actually made to install in a semi-permanent mode. It is called a Dashdaq and has the ability to both scan and log. You can also input an analog 0-5, that is how the wideband will be displayed and logged.
I fabricated a plate that will extend from the radiator down to the circular cross member. It will run parallel to the box and about an inch below the box. That will go on this week end. That will further reduce the both the convected and radiant heat gain on the air box. I will run some more test after that install.
201520162017