I agree that a K&N CAI will produce some hp without a tune, but it will not be anywhere near 18 hp. The following show the reasons why.
A research of MMFF's archives failed to yield any test results that show a K&N CAI producing an 18 hp/15 lb-ft gain when installed on an S197 without a tune. However, those numbers are an exact match for the gain produced by the K&N CAI in the 5.0 Mustang "Cold Score" link in your post. So evidently that article is the one you're referring to. But it should be noted that the K&N's 18 hp gain in that test included a 10 hp gain from a 91 octane generic tune, and its 21 hp gain included a 13 hp gain from an SCT tune. Hence, the net gain for the K&N CAI was only 8 hp.
Also, the dyno results on K&N's site show a 15 hp gain for their CAI without a tune. But according to the "Cold Score" test, a 6 hp gain was produced by simply removing the stock intake's hydrocarbon trap. And since the stock intake must be removed to install any CAI, then that means the K&N's net gain for their dyno test was only 9 hp.
Plus, Horsepower TV showed a gain of only 10 hp with a K&N CAI without a tune. That's only a 4 hp net gain after subtracting the 6 hp gained by removing the stock intake and its hydrocarbon trap.
Can someone feel an 4-9 hp gain? Possibly, but it's not going to even be close to the SOTP feeling that a 20-30 hp gain from a CAI/tune produces. And when that amount of gain is added to a tune's ability to eliminate the stock tune's throttle lag, the difference in the S197's performance is like night and day.
I'm not trying to get into a big fight over this and I don't want to make anyone mad. First, sorry your right, it was 5.0 mustang, not MMFF my mistake. But please go back and read the article I posted a link to carefully. I've pointed out a few things you missed below.
From the article the baseline numbers with the tune and without. Notice the 6hp increase from the hc trap removal is factored in so you shouldn't subtract it from the K&N test.
"Our baseline numbers were made with the car in stock trim, then we pulled the hydrocarbon trap from the inlet and got 261 rear-wheel horsepower and 282 lb-ft of torque."
and with the tune
"with a modest 91-octane tune, the car's baselinewas established at 271 rwhp and 289 rwtq."
And the following from the K&N Test. Notice they give two numbers, the first is without a tune (so they removed the tune for the K&N test), the second is with the 91 octane tune.
"Some of our participants didn't want any tune for their cold-air intake.Not only does this flaunt their engineering skills, but it also pointsout what a cost savings these systems are when a full dyno session witha custom computer flash can cost $200-$500, depending on the hourly ratefor your speed shop. We followed these manufacturers' wishes, and haveprovided rear-wheel horsepower measurements with just the cold-airbolted into position. But we also gave Ken Bjonnes the creativeopportunity to see what he could do; so you'll also see a dyno numberthat resulted from the CAI and an MD Motorsports tune."
So finally the numbers.
"Peak Horsepower: 279 (18hp gain)/(282 with SCT tune)
Peak Torque: 297 lb-ft (15-lb-ft gain)/(300 lb-ft with SCT tune)"
If you subtract the baseline for the car with the 91 octane tune from the tests on the other intakes most come up with around 18hp from just the CAI. So if they yield 18hp alone why is it so hard to believe the K&N would yeild 18hp? As for why HP TV only got 10hp? I think maybe the simple answer is that HP TV left the hc trap in. That accounts for ~ 6hp. Plus every car is different, not everyone will see 18hp. The 15hp claimed on K&N's site is probably an average of several dyno runs on different cars. Finally, maybe HP TV used a mustang dyno and 5.0 mag used a dynojet. Mustang dynos yield slightly lower numbers.
As they point out in the article the main problem with the K&N is that it is pretty much maxed out before the tune (as evidenced by the meager gains from adding the tune). So if you plan on adding a tune you should probably go with a different intake with a larger diameter tubing.
sound.
Like I said, I agree that it adds hp no doubt but I felt the butt dyno was very little. I know you felt the difference, were you stock at the time when you installed the K&N? My buddy gashog was stock with just gibsons and a K&N maybe that's didn't make much of a difference to him much at all
