So does anyone want to buy my brand new in the box complete with oiling kit K&N filter?

Everyday low price of $200. It will give you a 20hp* increase across the board.

But wait there is more click to buy it now and I'll ship it for free...











*Some minor tuning required



PS: And it is only 5 years old, box may be a little dusty...

 

I had further conversations with David Lloyd on this very subject. Based upon our combined observations the direction of the arrows on a non-Porsche filter can point in the direction of airflow or point in the direction of 'UP' depending on what we do not know (manufacturer? Moon Phase?) The actual Porsche filters have "oben" stamped on the side of the filter that faces up. (See guys: I do remember some of my German from time-to-time ) Without the 'oben' as a guide the correct placement (supported by Louie's excellent data) is for the 'fat' side of the filter to be up and the side of the filter allowing maximum air volume under the filter to be down (towards the MAS.)

 

thx Dave.

In your original thread 'Powerless GT' you talk about not being able to out drag a Camry and a lack of top speed. Did replacing the HS fix the issues somewhat or did they remain as you have other issues?

I ask as I have no other reference but this thread (who started this anyway?) leads me to believe I'm missing hp somewhere with all maintenance performed including a rebuilt MAF from Mr Speake..........no chirp from the tyres ever.

 

I believe the situation with the K&N is not one of mass air flow being more or less. The problem is that the air flow is mixed up and turbulant. Take a molecule of air and pass it by the wire, as in an eddy current in water, two or three times, and it cools the wire as if it was two or three new air molecules. The LH goes richer. Then a rarified bit of air goes by and the LH goes lean. This happens many times per second. The average air mass per second may be the same as with a stock filter, but the rapid variations screw up the engine operation. You are right about the S4/GT/GTS being too rich at the top end. That's normal. Not correct, but normal. Usually too lean below 3500 too.

 

Ignorance is bliss, I ran a K&N for 2 years! Now I will have to spend energy and vascilate on what to do!

Dan

 

I was not hyperbolizing about not being able to outrun a Camry.

Replacing the HS made a very dramatic, obvious, and immediate improvement in hp. I knew within 50 yards of driving that the biggest hp issue had been dealt with. One thing to consider also - I had the '91 GT to compare with so my butt-o-meter was well-calibrated. I can most definitely outdrag lots of stuff on the road now with the '89. (Theoretically. From a realistic standpoint it has other 'issues' not-yet-published that require attention before heading to a race of anysort. I knew this '89 was a 'project' car when I e-bayed it and it's living up to that expectation.)

I recall a number of posts from folks that found HS faults with a Hammer or Spanner and were surprised since they felt that the car was otherwise operating with good power. It seems those 'surprise' HS failures are more common that my 'dramatic' HS failure.

You've done all the maintenance suggested in the "Powerless" and this thread? Injectors cleaned and balanced? Vacuum system verified? Fuel pressure? Breather hoses all in one piece? You mentioned earlier that an under intake refurb was still to be done? (Just double-checking here)

I would suggest first to calibrate your butt-o-meter with another '88 auto or to have someone with a calibrated butt-o-meter drive your car. Ideally you could run yours on a dyno to see where it is at by the numbers. I really think that once you get to the 90% or 95% state the butt-o-meter isn't the best way to determine how much power isn't there. I was surprised that my '89 only put 270 to the rear wheels. I had expected it to be a little down from my '91 but not by almost 10% after the dramatic improvement of the new HS. Also, the A/F trace from a dyno run can sometimes provide clues to missing horsepower.

 

Didn't mean to suggest that you did.

[/QUOTE]Replacing the HS made a very dramatic, obvious, and immediate improvement in hp. I knew within 50 yards of driving that the biggest hp issue had been dealt with. One thing to consider also - I had the '91 GT to compare with so my butt-o-meter was well-calibrated. I can most definitely outdrag lots of stuff on the road now with the '89. (Theoretically. From a realistic standpoint it has other 'issues' not-yet-published that require attention before heading to a race of anysort. I knew this '89 was a 'project' car when I e-bayed it and it's living up to that expectation.)

I recall a number of posts from folks that found HS faults with a Hammer or Spanner and were surprised since they felt that the car was otherwise operating with good power. It seems those 'surprise' HS failures are more common that my 'dramatic' HS failure.)[/QUOTE]

I searched for HS faults and there conclusions; your thread was the most comprehensive with the exception of the diagnosis which you've explained.



[/QUOTE]You've done all the maintenance suggested in the "Powerless" and this thread? Injectors cleaned and balanced? Vacuum system verified? Fuel pressure? Breather hoses all in one piece? You mentioned earlier that an under intake refurb was still to be done? (Just double-checking here)[/QUOTE]

Yes indeed an intake refurb has still to be done at which time I'll do all and more; injectors, hoses, WOT switch, ISV, flappy, dampers, regulator, related fuel hoses, gaskets, knock and hall sensors et al.

Not much opportunity to verify my car against another in this remoteness; perhaps if the snow holds off I'll join the author of this thread on his fall trip and we can get it on.

Might be cheaper just to order the spanner and see what it says; maybe its fine and I'm just expecting too much.

 

That's more or less what I was trying to get at indirectly. But your post kicked my post's *** and not only because it had all that data to back it up.

I believe that the flow through the MAS with a stock filter also has to be turbulent. But, to whatever is conditioning the signal from the wire and to the control system that accepts the signal there's a difference between lots of little eddies and a few big eddies. Regardless, it seems logical to conclude that the MAS calibration and or signal conditioning for the control loops were tuned for the stock filter. Your data supports the logic it would seem.

Whether or not you could calibrate a MAS for a K&N seems acedemic. Why bother? So you can have Outlook remind you to clean and oil your filter? For 1 or 2 rwhp?

Are we at dead horse status on the K&N for 928s yet? Is it glue?

Why don't we pile all those 928-sized K&N filters into a pile and have a bonefire? Does the oil burn well?

 

Almost.... Getting there....

OK, dead... (I think)

 

Brett, about your question on the mesh on either side of the MAF. Hot rod magazine did some tests a few years ago, and the mesh really restricts flow. Removing it will get you some definite gains, but it will totally expose a very fragile wire to anything going down the intake. Not my idea of an upgrade.

 

Hi Daniel,
It is true that the mesh causes some restriction, but I don't belive it is the most significant restriction in the total 928 inlet system from air intake to valve seat...