I dyno’d my car at the incredible BMW/Mercedes Benz/exotic car met Timmayfest last weekend. They were doing two pulls per car. I used the opportunity to test the K&N DryCharger water resistant air filter rain covers. Previously, I have run at the dragstrip with and without them on the same day and did not see a difference in times. I wanted to see if the dyno would show any loss of HP from intake restriction with the Drychargers.

Background: I have a custom dual intake with full length 3” tubes and dual K&N filters right behind the grill.

Run 1 was with the Drycharger air filter rain covers installed. 409 RWHP, 415 RWTQ.

Run 3 was with the Drychargers pulled off. 407 RWHP 413 RWTQ.

dyno6-6-2014TimmayfestW676runs1amp2_zpscf4aa88f.jpg

She made 2 HP more WITH the covers installed than with them pulled off. I don’t think the covers add HP. But they clearly don’t subtract a meaningful amount either. The difference is within the variance from pull to pull on the dyno. I am going to leave the covers on all of the time.