More on the mass air flow cone

Indeed, just the fact that there is conflict has driven me to determine that there probably is not significant difference with K&N, further, I can tell you how K&N can say its filters work.
Statistically, you just keep testing cars. Of all the cars that can be possibly tested, surely some can benefit from more air flow. Ideally, if the number of cars that can benefit is greater than the number of cars which, for whatever reason, lose power, then the average of all the cars' HP gain will be greater than 0. Our null hyp is that there is no difference, or that the average of all cars, some losing power, some gaining, some with no difference, is 0 after many trials. But if they test enough, eventually, I'm sure they can bring that average to above zero to a significant level.

Does that mean Porsches benefit? From what you guys are telling me, no it doesn't. But that doesn't make their claim statistically invalid. Which is why you never use statistics to prove a single case! All you can say is, well, if I pull random car X from a heap, there is a k% chance it will benefit from K&N and only a l% chance it will not. There might be a small chance it actually causes the FI software to fail. And it's not hard to see why. They program those with upper and lower bounds I'm sure.

But it does mean this: There is a hell of a lot more room to work under that hood with the big black box from hell out of the way!
Other than that, I agree, I'm probably just revving me engine.


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Kurt B
1984 911 Carrera Cabriolet
75 914 1.8

Kurt you sound like my wife (also a statistician) but she looks at the probability of when/if mine will run again looking at a random sample of time that I was working on it.....

If you like the sound let her sing.

s

Hahaha! I am the exact same way. My signature really should include:
.."More dangerous with a Haynes manual and set of tools than Oswald with a laser scope..."

Anybody know if the cone filter can be used on an '83 911?

Yeah, they have a kit for most years.

So what now? Should we stop buying cone shaped sports airfilters? Even if they don't give any extra HP they do offer better looks and room in the engine bay. Also you get a better sound. What do you think will happen if I install one on my 84 911? Will the ECU still behave nicely or will it be confused by the new intake? I don't want to replace my ECU with an "optimised" one.

K & N filters let more particles through into the engine.

They dont filter the air as well as a stock air filter.

So as there is no increase in performance, I would not fit one.

Alex.


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911 2.7S Targa
email:alex@cascade.f9.co.uk

Mikkel,

I put a K&N Cone Filter on my '84 Carrera about a year ago. I had no problems with the Motronic brain and the new air filter.

Regards, Bruce

My own experience with the PowerFlow filter...it looks sexier than the stock air box, but I noticed no gain in power on my '95 993. Also, I found myself unconciously driving at lower revs as you would get an annoying buzz around 4500 rpm and up. Maybe that's music to some of you guys but eventually I found it irritating. The factory "sound package" has an air box with a big opening on the side...I don't know if it makes any difference.

In isolation the addition of a cone type filter may be questionable, but start adding mass air flow sensors, hot cams, free flowling exhausts etc, and you will see very quickly that the stock air box / filter starts to hold back air flow at high rpms.