When accelerating I feel a slight hesitation right around 3,000 to 3,200 RPM in every gear. Could this be the vario-cam system making changes in this RPM range??

I have noticed it as well. I think the variocam+ kicks in around 4000-4200RPM. Not sure what is causing the hesitation.

The graph in the brochure for the Cayman S shows a distinct dip in torque between 3-4,000 rpm. That's probably what you're feeling.

I had read quite a bit about this before I purchased the car, but to be honest this "delay" is barely noticeable in mine.

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oh well...

Yes, as others have said, this hesitation is a dead spot in the torque curve. It's very disappointing to be honest. It really shouldn't be there as you're forced to use a much higher rev range (4,000+ rpm) to get some decent torque.

To be honest it doesn't bother me. I barely notice it. Nitpicking are ya?

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Mike
2006 Midnight Blue Cayman S

Blame the Swiss...they introduced drive-by noise measurement regulations some years ago....these regulations have been adopted by the European authorities as the way to go (Porsche is a European manufacturer in case you hadn't noticed , and therefore have to comply with the Euro regulations)... The measurement of acceptable noise under full acceleration is taken at the distance where the vehicle in question will be travelling at approximately 40mphunder full acceleration from standstill , and the way to reduce noise(er..comply with the regs.)at this point is to program a reduction in power production at that speed in first gear.....We are not the only ones to note a 'flat spot ' in our engine tuning curves...Bikers have had to put up with it for years...The remedy is straightforward....Just retune the ECU (chip) , and hey presto...your vehicle goes much better , and makes slightly too much noise....Oh dear....

This flat spot has gone bye-bye since I De-snorked intake and installed the EVO V-flow. This flat spot was really noticable while gradually accelerating in first gear. It is now completely gone.

Silversled I have desnorkled my car, and it sounds maaarvelous. I believe I also get a better response. How much of a difference did you get with the EVO-V Flow? I am interested in performance and sound. i do not need it any louder, but I am willing to put up with a little more sound. How does the engine sound and perform at idle, does it hessitate?


Thank you

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Having fun in Puerto Rico

Jaica,



I'm sure you've seen my replies to post,

EVO Cayman S V-Flow


I installed the V-flow first and it was louder but not significantly. Seat of the pants evaluation did indicate smoothing of the powerband. It rev'ed more freely as well. I desnorked and everything that the V-flow gave me, it just gave more. My honest opinion is that a BMC filter will probably give similar results as the V-flow but at lower cost. It will be easier to install (although the V-flow was not hard), and any performance shortcomings compared to the V-flow would probably only be noticed by the dyno. Of course the true test would be a back to back dyno test session involving the stock, BMC, and V-flow filters.



Other than the noticable growl, my engine idles like stock but sounds and performs better than stock.

Thanks for the response Silversled.


Does anyone know if the BMC and the K&N Filter are basically one and the same?

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Having fun in Puerto Rico

tstires,

I also notice the part throttle bobble at 3K. FYI - I desnorkled and did not find any change - still has the bobble. I do not experience the bobble at full throttle. My initial concern was that it might be the catalytic issue that others have experienced - I guess it is a problem with the ECU map??

-g

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Greg Merril, CEO
InterAction Laboratories
'Making the digital world a more physically active place'
www.ia-labs.com

There might be two things at work for me:



1) Desnork + V-Flow



or



2) Have not driven car long enough for ECU to adapt to desnork and filter. Maybe the bobble will come back.

FYI - The 3K RPM hesitation is normal for all modern Porsches, at least for all 911s and the Cayman. I had a 2000 Boxster S that did not have this behavior.

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97 Turbo | 06 Boxster S | 06 Cayman S (sold)