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Power blip at 3200rpm

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Old 07-04-2011 | 09:30 AM
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Default Power blip at 3200rpm

I've noticed a blip in power (increase) while accelerating, usually at 3200rpm.
Generally, I've noticed it under moderate acceleration around town. Seems consistent in all gears, but I notice it most in 2nd and 3rd as that's where I drive through 3200 the most. This happens with the accerator steady, just letting the engine push itself up to speed.

Anyone else experience this? Is it cam/timing related?
Old 07-04-2011 | 10:15 AM
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Variocam...
Old 07-04-2011 | 10:51 AM
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Yep, Variocam. Just tell your friends its your normally aspirated turbo kicking in!
Old 07-04-2011 | 11:09 AM
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So, this is exactly what I figured. I should have known the term 'variocam'.

Theoretically speaking, wouldn't this blip cause a problem on the track? Accellerating out of a long corner, at the limit of lateral traction, wouldn't the blip cause a wiggle?

I also noticed this blip at a DE event. I wasn't push the car very hard but, rather, was working on being as smooth as I possilby could be. This blip was starting to bug me. I wondered if my instructor thought my throttle application wasn't very smooth...
Old 07-04-2011 | 11:24 AM
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It should be Smooth. If its Rough you have a Variocam problem. have it Diagnosed
Old 07-04-2011 | 11:58 AM
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Technically, a simple variocam comes in much higher (as on earlier 996's).

Variocam Plus -- comes in about 3,200 rpm and you can feel it as a significant push and the sound of the engine changes. With a passenger & light throttle, it can feel like you're not driving smoothly. Occasionally, I'll tell a passenger what's going on as the engine paramters shift from emphasizing torque to emphasizing hp.

Personally, I'd prefer that it came in somewhat more gradually rather than a solenoid-style on/off. But....I prefer to have it than not.
Old 07-04-2011 | 11:58 AM
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I find it's always different. Sometimes harsher than other times... It all depends on how much gas you give it and or if there is an actual problem.
Old 07-04-2011 | 12:15 PM
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Originally Posted by Zookie
It should be Smooth. If its Rough you have a Variocam problem. have it Diagnosed
I don't think it's so rough that I have a problem. It's just that I notice little things.
Old 07-04-2011 | 12:26 PM
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I haven't noticed it at all, but now you're making me want to go for a drive just to test it out. After the last thread about this I tried paying attention during my commute and there was nothing obvious at any RPM in the 3k to 4k range.
Old 07-04-2011 | 12:32 PM
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variocam kicks in around ~1400 rpm

PLUS is another story
Old 07-04-2011 | 01:29 PM
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Originally Posted by Yomi
I haven't noticed it at all, but now you're making me want to go for a drive just to test it out. After the last thread about this I tried paying attention during my commute and there was nothing obvious at any RPM in the 3k to 4k range.
Are you serious? There is either a problem with the car or you have to be more observant!!
Old 07-04-2011 | 01:33 PM
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If you're on the track..you really shouldn't be in the 3000 rpm range much....keeps the revs higher than that.
Old 07-04-2011 | 02:45 PM
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That "blip" is one of my favorite features.
Old 07-04-2011 | 03:11 PM
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on mine it is more noticeable with light acceleration in first and second. accelerating hard it is more difficult to feel, other than the rush of power.
Old 07-04-2011 | 04:53 PM
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Originally Posted by Targatoo
I've noticed a blip in power (increase) while accelerating, usually at 3200rpm.
Generally, I've noticed it under moderate acceleration around town. Seems consistent in all gears, but I notice it most in 2nd and 3rd as that's where I drive through 3200 the most. This happens with the accerator steady, just letting the engine push itself up to speed.

Anyone else experience this? Is it cam/timing related?
Depending upon one's sensitivity there can be a bit of a bump in power at around 3K rpms. The intake manifold has resonance flaps that are activated at 3K and when they're activated this helps the engine to breathe better.

It can feel like the engine is coming on the cam, so to speak.

Sincerely,

Macster.


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