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Thoughts on sports exhaust

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Old 08-30-2014 | 12:39 PM
  #46  
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Cars should not be revved past 4K at idle,PERIOD!(Any car!!!)
With a light flywheel and an engine spinning so fast,I can see why Porsche wouldn't want you to spin it like mad without any load. I can only imagine the accelerated wear on the engine doing this often.
Old 08-30-2014 | 01:03 PM
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Originally Posted by neanicu
Cars should not be revved past 4K at idle,PERIOD!(Any car!!!)
With a light flywheel and an engine spinning so fast,I can see why Porsche wouldn't want you to spin it like mad without any load. I can only imagine the accelerated wear on the engine doing this often.
I'm not sure you one can rev past 4k at idle cause idle is below 1k.

But anyway, it revs past 4k in launch mode.
Old 08-30-2014 | 01:06 PM
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Originally Posted by frayed
I'm not sure you one can rev past 4k at idle cause idle is below 1k. But anyway, it revs past 4k in launch mode.
LOL!

I stand corrected. That's what happens when you post without having your morning coffee.
I meant revving standing still,not in gear,no load.
Old 08-30-2014 | 01:06 PM
  #49  
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Why on earth would you want to rev it in neutral higher? WTF?

"Hey look at me...Vroom Vroom Vroooooooooom....I'm an idiot!"
Old 08-30-2014 | 01:11 PM
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I will admit though the neutral feature is kinda fun. Though not as natural to use as clutch pedal pressed so you can blip the throttle for fun.

Here's the thing. Pretty much every day, someone asks me to start it up so they can hear it. Fortunately a quick blip to 4k produces some nasty gurgles and pops.
Old 08-30-2014 | 04:32 PM
  #51  
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vroom vroom helps attract strippers.
Old 08-30-2014 | 05:45 PM
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Originally Posted by frayed
Put it in gear pull both paddles and rev to your hearts content. It'll rev past 4k but not sure how high it'll go
cool. youve tried it?

and it works from stationary?

not saying i will be doing it, but once or twice to 7-8k would be nice.
Old 08-30-2014 | 09:23 PM
  #53  
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Yes tried paddle neutral and you can rev as high as you like.
Old 08-30-2014 | 10:53 PM
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Originally Posted by Paul Graville
Yes tried paddle neutral and you can rev as high as you like.
thanks
Old 08-30-2014 | 11:17 PM
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Ahhh. The strippers. Will have to start a New thread
Old 08-30-2014 | 11:33 PM
  #56  
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Originally Posted by Paul Graville
Yes tried paddle neutral and you can rev as high as you like.
Yes that was my experience too as posted on other threat. I haven't used launch control yet but I have launched the car a few times using paddle neutral in manual and it's been skit if fun! Call me a boy racer :-) !
Old 08-31-2014 | 04:27 AM
  #57  
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I saw my first one in the flesh yesterday at the gas station and when it started up it was pretty quiet at idle and when it went off slowly. Does it really sound as good as a 458 or a Maserati? Those are music to me
Old 09-01-2014 | 08:37 PM
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OK. So backpressure at low revs = tq, no? Lower backpressure = more hp up top generally.

The valve closes from 3k to 4k rpm even in sports mode.

Porsche states:

As was the case with the predecessor, the new 911 GT3 also offers the driver the possibility of increasing the pull of the engine in the mid rev-range at the press of a button. When activated, the back-pressure in the sports exhaust system is further reduced, improving gas exchange and thus increasing the torque between 3,000 rpm to 4,000 rpm by up to 35 Nm.
I'm having trouble believing the only reason the valve closes is only b/c of sound, except for maybe if there are resonance issues in that rev range, which is totally possible based on my experience with aftermarket exhausts on other cars.
Old 09-01-2014 | 09:09 PM
  #59  
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Originally Posted by Paul Graville
Yes tried paddle neutral and you can rev as high as you like.
Interesting. I haven't played much with paddle neutral. Paul, did you try revving in paddle neutral with the car moving or standing still? I think I've only tried it with the car moving and could have sworn it wouldn't rev beyond 4K but maybe I'm not remembering correctly. OTOH, I haven't tried it from rest and it makes sense that you could rev beyond 4k since I think I've read of testers doing burnouts that way. I'll have to go play with it....
Old 09-01-2014 | 09:11 PM
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Mike, I was moving when I got over 4k. I think I've done it stationary in the past too. It's the burnout button!


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