Air filter lid off
Obviously with the lid off there's more chance for heatsoak, but 15 whp? That's what 21 hp at the crank?
While the power number cranked out by my spreadsheet may be a bit off, the acceleration times were consistent. To go from 3700rpm to 7800rpm in third gear, taking the lid off increased the time ~1.3 seconds. Again, 2 runs with the lid, 2 runs without, same stretch of road, same direction (eliminating any elevation/grade variation and minimizing wind variation) all in about a 5 minutes stretch. I can't remember the exact ambient temperature, but I think it was around 75F-80F that day. At 7800rpm, the datalogs showed IAT of 133F vs. 144F and 1 deg of timing difference. In the mid-range, there was a difference in timing of a few degrees which accounts around 20lb-ft torque difference. That's where a big chunk of the time gain was from.
I would think the hp loss is reduced in the winter time like temperature under 45F? Not sure if the hp loss reduction vs the temperature drop are directly proportional to each other.
Last edited by rudyy; Aug 29, 2017 at 12:06 PM.
A previous poster claimed 15 whp was invalid due to his track experience lid off vs other S's lid on. You pooped on the guy with spreadsheets and analysis, I was just pointing out the guy with the counterpoint argument s test was equally, if not more flawed...
No shit Sherlock I thought that was obvious and didn't need to be stated.








