P.J.S.

^
ain't that the truth!

to all - I will post up a dyno sheet tomorrow that details lid closed dynos with no huge fans in the following set up:
1. stock configuration sport off
2. stock configuration sport on
3. kn kit sport on

dynojet

I picked my car up from my tech (regeared) and he had a copy of the dyno results

you will see what I saw and let me know if I am mistaken... I am not a tech so I welcome an explanation that I may not have gotten.

va122

regeared? What did you do PJ?

P.J.S.

^
revised 1-4 gears
8:33 ring and pinion
2 piece cup shaft
all guard stuff - ring and pinion purchased from guard but made by Ricardo

va122

Nice Dude! I have the 8:33 and love it!

P.J.S.

just picked it up so have not tracked it yet but so far so good...

P.J.S.

okay... here is what I saw when I thought the KN was a good deal for $300 (see attached)

This is not my RS but it is a 2007 RS that was stock at the time.

difficult to see the actual lines as they are so thin etc... but in summary here is what it says:

Green line -- stock air box, sport off
352 hp 264 tq

Red line -- stock air box, sport on
363 hp 266 tq

Blue line -- KN box fitted, no hypercharger sock (or whatever they call it), sport on
373 hp 273 tq

All pulls with car hot, deck lid closed, no fans and on the same day within 40 mins of each other so same ambient temps etc... car never left the dyno inbetween pulls.

you can see it makes hp/tq the whole curve (or at least I hope you can see) and it specifically makes the largest gains around 6500 rpms

I am also under the assumption that the "ram air effect" would improve the numbers... not hugely but to some degree.

I am no dyno whiz and I welcome alternate explanations.

911SLOW

I don’t want to start a dyno war again its beaten to death.

But in a few words real dynos are the engine table dynos with controlled fuel cooling temps and ecu. They are expensive and not easy to find or operate.

Rolling dynos are usually inaccurate but some of them if used properly can help setup or test a cars component vs another, or help you find a malfunction etc.

Modern cars are very hard to dyno test correctly on a rolling dyno, and to extract valid data you need to do the runs on the same day and weather conditions and ambient temperature and pressure must be close because SAE or ISO correction factors are not accurate.
You need hi velocity fans properly placed to the front radiators and on the engine area (tricky in a 911) also you have to monitor the ecu to get intake temps and ignition timing if possible to verify that the cars ecu doesn’t jump timing maps or pulling back and that ecu is not in an “adaptation” cycle.
Most importantly you have to make many runs, let's about 8-10 until you see your results stabilizing and then take an average of the ones that are stable and close.
Between runs you have to cool the car not by turning it off but running to allow water and oil to circulate.


By using the above methods you can hope that your results reflect reality and are valid. Just doing two runs back to back is probably going to produce meaningless results.

The dyno page you present here is useless for me, because it was not done properly and also was done by the tuner / seller.

In October when you retest I can help you standardize a procedure to dyno the KN and stock box with KN or BMC panel filter and then post the results here. I am confident that they will be very similar to mine.

P.J.S.

these are averages based on multiple pulls and sae corrected
not weighted to get me to buy anything -- my tech is not that way -- he sold it to me at his cost -- he is not a parts mover type of guy.

I agree with your assessment of rolling dynos BUT dont look at the numbers so to speak...just look at consistent parameters and a gain or loss

Assume that the tech has my best interest at heart and has built and dyno'd many cars etc... his primary job is fabrication and he has built literally hindreds of headers and exhausts for many different types of cars... he uses the dyno to verify his gains and is very familiar with how to operate it and proper protocol etc...

He was skeptical of the the KN set up...

Dyno jet is not the best but it does provide a means to a consistent measurement if the protocol used is reasonable... right?

Also, my tech does not own the dyno, it is not at his shop etc... he is familiar and has done hundreds of dynos on this particular dyno...

Again, please do not read this the wrong way... I am partially agreeing with you... rolling dynos are not the best but in the absence of a better alternative can we agree that if protocol is followed, they can be consistent in measuring power difference between mods? maybe... I acknowledge that there are a lot of easy to manipulate parameters but my tech was just as curious as I was... so he tested.

I did not pay for this dyno or my dyno -- this is something he wanted to try as an alternative to modding the stock airbox... as this would allow his customers to retain a sotck airbox should they ever want to go back to stock for resale etc and the KN kit is less costly than paying him to modify the stock air box... so he wanted to try it... to see if it was good value for his customers.

I do not have a dog in this fight so to speak... I get that most of you think the kn kit is ****... that is okay with me... I do not work for KN, I do not sell car parts, just enjoy the discussion.

Curious that when provided with a dyno chart, then not only is the kit ****, but the tech does not know what he is doing (wrong) and the dyno machine is crap.

I have nothing to gain by convincing anyone of anything so really no point in continuing... I will try to get my hands on a BMC and see what the same dyno says with that and the stock box... given that the kn is crap, I will expect the BMC/stock box to peg the gain meter on the dynojet

911SLOW

These are not averages they are single runs, 3 of them timed on your dyno sheet all made within an hour.

I spend two days on MAHA LPS3000 dyno testing filters for my car. Wish this setup worked because it was cheaper than the alternatives and lighter but it didn't.
Besides I don't have nothing against you, I don't even know you, or your tuner or K&N.
On the contrary I believe that their panel filters are the best I just use BMC because they are cheaper here.
I don't have a shop, I don’t sell anything and I don't even care about wining a forum contest on "who is right".
I just want people here to know facts, not fiction so that they can decide for themselves.

Once you test your setup as I described earlier you 'll see what I mean.

Best,

silverboy

It's amazing how strong the under currents are for K&N. I've also used their product for other cars with some degree of success which is why I thought for US$300 - why not. The dyno numbers speak for themselves. My butt dyno speaks for myself - ha ha ha. It's my car...I am not affiliated w/ K&N and am happy the modest gains and induction sound and that ultimately is what counts.

911Slow - I'm pretty impressed with your knowledge of Dynos. Good for you.

Peace guys and enjoy the road, the sun and life.

P.J.S.

you are right... he showed me another sheet with a bunch of runs and averages and I took this one, as the averages sheet showed the same info over and over... showing his results were repeatable.

I know you have nothing against me... and I have nothing against you... might be diffiuclt to read the tone in which it was written...

So if I have him test a BMC filter/stock box using the same dyno and the same protocol, then logically I should see increased gains... signigicantly increased gains even... or is it the dyno itself that is not worth using? of course there will be slight differences based on ambient temps etc.. but controlling all that can be controlled, the BMC/stock box on a dyno jet logically according to you should make more power...

I do nto thik a MAHA3000GT dyno exists in my area... so this is not an option for me.

911SLOW

Amen brother.

Don't worry about it. We are cool and I enjoy this.
Do the test right in any dyno just for the fun of it. Don’t expect anything major we are talking about few hp and Nm in any case. I will try to dig out my old dyno sheets, I have most of them in excel files, to compare .

996FLT6

Cmon guys 911slow is **** about everything- he lives in Greece : ). Mike

911SLOW

^ Mike beware, Victor is Greek too.