treynor
Enthusiast
Like many, I received a pre-correction K&N intake complete with "the whistle". I noticed that the car didn't seem any faster after installing the intake (understandable, it's hard to feel the difference between 475 and 485 RWHP) though it didn't feel any slower either, and that it tended to buck significantly at low RPMs in 1st gear. I was disturbed, however, to discover that it had lost 12 HP and 15 ft/lbs on the dynojet dyno!
I promptly went out and bought the two correct-size drill bits, removed the intake, and drilled out the two holes to their proper diameter. Although from external inspection the intake holes appeared roughly correct, they were WAY off on the inside, and a lot of material was removed in the drilling process before the holes were the correct size. I cleaned out the intake and reinstalled it, then went for a spin.
In a word, WOAH. There was a dramatic difference in power, especially at the upper RPMs, and the whistle and bucking were both completely gone. I'm normally a sceptic about the butt-dyno (you expect it to be faster, so you think it is) but in this case there was no mistaking the power difference. It feels like at least a 20 RWHP improvement, possibly more.
Conclusion: anyone who has purchased a K&N intake needs to check the crankcase and IAC holes carefully, and if in doubt drill them to spec. You will be very pleasantly surprised at the difference if you've been driving around with one of the out-of-spec intakes.
Also, now that I have the bits, I'll volunteer to help out anyone in the Bay Area who wants to swing by with their SRT; just drop me an email. The whole thing just takes 30 minutes.
I promptly went out and bought the two correct-size drill bits, removed the intake, and drilled out the two holes to their proper diameter. Although from external inspection the intake holes appeared roughly correct, they were WAY off on the inside, and a lot of material was removed in the drilling process before the holes were the correct size. I cleaned out the intake and reinstalled it, then went for a spin.
In a word, WOAH. There was a dramatic difference in power, especially at the upper RPMs, and the whistle and bucking were both completely gone. I'm normally a sceptic about the butt-dyno (you expect it to be faster, so you think it is) but in this case there was no mistaking the power difference. It feels like at least a 20 RWHP improvement, possibly more.
Conclusion: anyone who has purchased a K&N intake needs to check the crankcase and IAC holes carefully, and if in doubt drill them to spec. You will be very pleasantly surprised at the difference if you've been driving around with one of the out-of-spec intakes.
Also, now that I have the bits, I'll volunteer to help out anyone in the Bay Area who wants to swing by with their SRT; just drop me an email. The whole thing just takes 30 minutes.
