Porsche's new philosophy with the GT3 according to AP
03-27-2017 | 04:29 PM
#122
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Here is one version that was later updated with a slightly different R&P for 911R/991.2 GT3 Manual (attached below):
I think this is the most recent thread (data evolves throughout - see post 39 for speed in gears)...
https://rennlist.com/forums/991-gt3-...ar-speeds.html
Bottom line is that the 991.2 GT3 Manual gearing is awesome and will make everyone happy, except those looking for quiet cruising and low fuel consumption at high speeds.
I think this is the most recent thread (data evolves throughout - see post 39 for speed in gears)...
https://rennlist.com/forums/991-gt3-...ar-speeds.html
Bottom line is that the 991.2 GT3 Manual gearing is awesome and will make everyone happy, except those looking for quiet cruising and low fuel consumption at high speeds.
03-27-2017 | 04:49 PM
#123
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Here - I've just made a new chart with 3.77:1 Final Drive (Remember that speed in 6th in Drag Limited to 199 mph at close to 8,250 rpm). You can also see at what RPM the next gear takes over if you look directly down below redline of previous gear. Also remember that despite both GT4 and GT3 getting over 80mph in 2nd, GT3's gearing is vastly lower since it's doing 9,000 rpm there rather than only 7,800 rom):
03-27-2017 | 06:02 PM
#127
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03-27-2017 | 11:24 PM
#128
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911.2 GT3 4.0 engine has better performance than the RS.
Max power and torque on paper are the same but the 911.2 GT3 4.0's max torque arrived at 6000rpm instead of 6250rpm (RS).
Max power of 500hp are both arrived at 8250rpm.
The 911.2 GT3 4.0 also has 200rpm more to play with.
The 911.2 GT3 4.0 has more power under the curve.
Max power and torque on paper are the same but the 911.2 GT3 4.0's max torque arrived at 6000rpm instead of 6250rpm (RS).
Max power of 500hp are both arrived at 8250rpm.
The 911.2 GT3 4.0 also has 200rpm more to play with.
The 911.2 GT3 4.0 has more power under the curve.
Power curves are near identical to me on both hp and torque. One curve Nm/Torque. On torque curve RS is blue other is Kw/hp where RS is red. No meaningful difference. If you think your butt can feel the difference in 200 rpm you have a very sensitive rear.
In fact the "9000 rpm" red line produces nothing but diminishing returns based on the power curve. In fact, it appears from the power curve the RS actually is generating more torque from 6000 to 8000 rpm while the .2 is lower and dropping all the way to 9000.
03-28-2017 | 01:12 AM
#130
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From: The way to hell is paved by good intentions “Wenn ich Purist höre...entsichere ich meinen Browning” "Myths are fuel for marketing (and nowadays for flippers too,,,)" time to time is not sufficient to be a saint, you must be also an Hero
comparing .2GT3 vs .1 3RS
Max Torque at lower 6kRPM
and engine at higher 9kRPM for a total 450-750RPM increased range
(650 in 2nd gear 7xxRPM in3rd and up gears )
this engine flexibility and personality betweeen Broads and Track has radically improved
not to mention that this time .2 GT3 500HP
are really conservative
remember there are 9HP only from new valvetrain
and 20% less internal resistances
but i still personally prefer NAs with pdk-s because you need way more tq with manual
to really enjoy it
Max Torque at lower 6kRPM
and engine at higher 9kRPM for a total 450-750RPM increased range
(650 in 2nd gear 7xxRPM in3rd and up gears )
this engine flexibility and personality betweeen Broads and Track has radically improved
not to mention that this time .2 GT3 500HP
are really conservative
remember there are 9HP only from new valvetrain
and 20% less internal resistances
but i still personally prefer NAs with pdk-s because you need way more tq with manual
to really enjoy it
03-28-2017 | 05:32 AM
#131
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Seriously? LOL.
Power curves are near identical to me on both hp and torque. One curve Nm/Torque. On torque curve RS is blue other is Kw/hp where RS is red. No meaningful difference. If you think your butt can feel the difference in 200 rpm you have a very sensitive rear.
In fact the "9000 rpm" red line produces nothing but diminishing returns based on the power curve. In fact, it appears from the power curve the RS actually is generating more torque from 6000 to 8000 rpm while the .2 is lower and dropping all the way to 9000.
Power curves are near identical to me on both hp and torque. One curve Nm/Torque. On torque curve RS is blue other is Kw/hp where RS is red. No meaningful difference. If you think your butt can feel the difference in 200 rpm you have a very sensitive rear.
In fact the "9000 rpm" red line produces nothing but diminishing returns based on the power curve. In fact, it appears from the power curve the RS actually is generating more torque from 6000 to 8000 rpm while the .2 is lower and dropping all the way to 9000.
More performance is more performance doesn't matter about your insensitive butt can read it or not!
The graphs are for guidance only as the actual power curves will be slightly different.
What's to take home for the 911.2 GT3 engine is that
1. Max torque is at 6000rpm instead of 6250rpm of the RS
2. Max rev of 9000 rpm instead of 8600rpm of the RS so one can stay in a gear longer and also at a higher torque point after shifting.
03-28-2017 | 05:56 AM
#132
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As interesting as it is to compare these charts published by Porsche, I think it would be much more interesting to see comparison charts published by an independent 3rd party (SportAuto dynos motors when doing the Supertest). I still find it a little too convenient that the 991.2 GT3 makes exactly the same peak HP and TQ as the 911R and 991.1 RS, despite having a significantly higher compression ratio, an additional flap in the intake plenum, and less friction in the valvetrain (around 8-10hp worth, according to AP).
Yes, I agree.
Also the power and torque curves don't exactly match up when I use the below formula to reconcile
Power (kw) = Torque (Nm) X rpm / 9549
My take is don't take the power curves too seriously as it is for marketing purpose only.
03-28-2017 | 11:56 AM
#134
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AP admits that GT3 991.1 has DEFECTIVE engine
The total redesign of the valve train and oiling system is for a reason: the 991.1 has a defective design which leads to roached top ends.
'm surprised nobody has posted about this article today. It is an interesting short read with AP himself addressing many of our concerns about the 'fun to drive' factor of the new GT 3 car and how the new engine stacks up against prior super Porsches including the Carrera GT.
http://www.roadandtrack.com/new-cars...as-preuninger/
Jim
http://www.roadandtrack.com/new-cars...as-preuninger/
Jim
03-28-2017 | 12:11 PM
#135
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From: Colorado