Your findings of elevated IAT's is exactly what I experience with my N/A engine, K&N intake. With my SCT X4 datalogging, I found dramatic differences between the K&N intake and the stock intake. ~43 degree delta average once the engine is warm. There's significance here, with all other variables being roughly equal. Now the weird thing is that even while in-motion on the highway, with tons of airflow moving through the engine bay and through the intake itself, the IAT's are much higher with the K&N, like 138-145 degrees (with ambient being an admittedly hot 110+), and that would skyrocket to 168+ in some situations, especially when the A/C fan kicked on and started blowing all that hot air out the engine bay. I suspect the lack of shielding from the cooling fans and the engine bay itself, and I suspect that pretty metal tube.
With that high of an IAT, the engine is a dog unless you flog it. And mind you, that's sans turbos so you have to know the turbo-charged versions are hitting much higher temps.
Quote from: ShoBoat on June 28, 2014, 08:48:09 PM
Okay so my findings from last night at the track. I have to admit I was a little surprised at the results. First I did 3 runs with my modified K&N typhoon with the K&N filter. DA was terrible and my launches were even worse. That said I launched the same every time. 2K only waiting 2 seconds of break boost for each run. Then I did one run with the typhoon and the S&B filter, no surprise here 3 tenths slower than the K&N filter. I only did one pass as I could immediately feel the difference between the 2. I then swapped out the typhoon for the stock box, I let the car cool down for 30 min and began the process again same as above 3 runs. Data logging was done by my laptop and FORScan. So on to the results. On average the stock intake ran slightly quicker then my modified K&N typhoon, but only slightly on all the runs. The kicker is that IAT1 (the one in the CAI and stock air box) was reading 12C (22F) higher then the Stock intake.
Here are the 2 runs with nearly identical 60 foot times.
K&N Stock with K&N panel
60 1.935 1.936
1/8 8.421 8.397
MPH 83.88 84.24
1/4 13.081 13.036
MPH 103.95 104.54
I know the 60s were terrible, I was however trying to launch the car exactly the same every time. And for the most part it seemed to have worked. Times were only slightly lower with the Stock box, trap was 1 to 2 mph higher with the stock box. When comparing the logs from the runs I can see that the car did pull slightly more timing with the K&N CAI. The interesting thing from the logs was comparing IAT1, IAT2 and CAC temps. Even though at the beginning of each run IAT1 was reading 22F higher in the K&N CAI by the 3 second mark IAT 2 and cac closed to 10F by 8 seconds the 2 runs were only separated by 2F difference for IAT2 and CAC temps from the 2 runs with the different intakes. I am going to dig a little deeper into the logs, I would really like to better understand the differences. But at least with the modifications might have made a difference, I also think that the location of the sensor on the K&N CAI might be reading a bit higher than actual (if that is possible). I hope this makes sense. I will try to do a CSV export of the 2 runs for comparison from the logs.
Bottom line the stock box is still slightly better performing. And if you buy an S&B filter make sure its a lot bigger than the K&N its replacing.
