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2020 NEXT GENERATION 992 SPY PICS & RELEASE

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Old 03-12-2018, 08:54 PM
  #1531  
BCMgunner
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Originally Posted by TorqueChap
Subtle. I likey. From the 928 flush-style headlights to the 959-style rear wing. Seems larger than a 991.
agree with the above. First thing I thought when I saw the rear wing deployed was “959”.
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Old 03-12-2018, 08:57 PM
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Originally Posted by BCMgunner
agree with the above. First thing I thought when I saw the rear wing deployed was “959”.
A 959 style wing on the 992 would look awesome! What’s on those mules is about the furthest thing from that though.
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Old 03-12-2018, 11:56 PM
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I just saw this on a Volvo commercial. Yes, it was a Volvo commercial, not a Porsche commercial, but it caught my attention because it does show some similarities to the nubbin that is seen in the mule. Nubbin food for thought...
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Old 03-14-2018, 07:44 PM
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Originally Posted by Dewinator

360s rev higher than the 355 before or 430 after too.
Really? I thought all 3 tapped out at 8650
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Old 03-14-2018, 08:48 PM
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Originally Posted by INTMD8
Really? I thought all 3 tapped out at 8650
Hmm yeah I guess you’re right. It looks like the F355 and 360 engines are quite similar except the 360’s was flipped 180 degrees so you can change the belt without taking it out where F430 was a new design with the chain and 32 valves instead of 40.
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Old 03-15-2018, 10:13 AM
  #1536  
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Originally Posted by Dewinator


Hmm yeah I guess you’re right. It looks like the F355 and 360 engines are quite similar except the 360’s was flipped 180 degrees so you can change the belt without taking it out where F430 was a new design with the chain and 32 valves instead of 40.
360's engine isn't flipped but they did put an access panel in the bulkhead behind the seats for timing belt access.
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Old 03-15-2018, 11:09 AM
  #1537  
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Originally Posted by INTMD8
360's engine isn't flipped but they did put an access panel in the bulkhead behind the seats for timing belt access.
Oh I didn’t realize the F355 didn’t have a port. What’d they do to the 458 to get a higher redline if all 3 of it’s predecessors’ were the same? And how come 9k seems like a limit for road cars that nobody can break?
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Old 03-15-2018, 11:15 AM
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Originally Posted by Dewinator
And how come 9k seems like a limit for road cars that nobody can break?
Mechanical valve springs.
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Old 03-15-2018, 01:30 PM
  #1539  
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Originally Posted by worf928

Mechanical valve springs.
What do racing engines use instead of springs?
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Old 03-15-2018, 02:41 PM
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Originally Posted by Dewinator


What do racing engines use instead of springs?
Gas springs. Some motorcycles use a desmodromic valvetrain.
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Old 03-15-2018, 02:46 PM
  #1541  
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Originally Posted by Dewinator

And how come 9k seems like a limit for road cars that nobody can break?
In addition to the aforementioned valve springs, the other problem is bore and stroke. With an increased bore comes increased reciprocating mass, and an increased stroke yields higher piston speeds. This makes more revs materiologically impossible. The GT3 avoids this to a degree with Ti rods and crazy thin pistons.

It would be easy to zing a 2.5 liter V10 past 10K, but such an engine would be infeasible due to fuel econ/emissions regs.
Last edited by Argon_; 03-15-2018 at 03:15 PM.
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Old 03-15-2018, 03:12 PM
  #1542  
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Originally Posted by Dewinator
What do racing engines use instead of springs?
Originally Posted by Argon_
Gas springs.
Yup. Properly: pneumatic valve ‘springs.’

Not really suitable for consumer use as folks would forget to top-off the air tank every couple of hours and thus suffer valve crash...
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Old 03-15-2018, 03:14 PM
  #1543  
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Originally Posted by worf928




Yup. Properly: pneumatic valve ‘springs.’

Not really suitable for consumer use as folks would forget to top-off the air tank every couple of hours and thus suffer valve crash...
You could just put a compressor on the accessory drive, with a clutch and cutout switch. That would work.

10k RPM GT3.
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Old 03-15-2018, 03:18 PM
  #1544  
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Originally Posted by Argon_
With an increased bore comes increased reciprocating mass, and an increased stroke yields higher piston speeds. This makes more revs materiologically impossible.
No, just economically impossible for mass-market. You just have to use more unobtainium and super-expensivium in the alloys. And it helps when you can throw the engine in the trash after 20 or-so hours of operation.

Remember that F1 engine manufacturers were readying 20k-rpm NA V8s for the 2009 (IIRC) season when the rule book hammer came down limiting revs to 18k.
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Old 03-15-2018, 03:20 PM
  #1545  
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Originally Posted by Argon_
You could just put a compressor on the accessory drive, with a clutch and cutout switch. That would work.
Yeah, but then we’d have to listen to all the whining about vacuum cleaner noises.
Last edited by worf928; 03-18-2018 at 12:38 PM.
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