Consolidated 991RS thread
#5956
Rennlist Member
That will make this car a minimum of a 14-15 car. We did some back to backs in testing of an h-pattern vs a sequential gearbox in our BMWs in 2008 at Sebring. The sequential gearbox with no lift shifts was 1.5 seconds faster than the h-pattern in shifting alone. The .6 faster 0-60 already shows the extra speed this car has over the 997 4.0.
#5958
Nordschleife Master
#5959
Addict
Rennlist Member
Rennlist Member
What sort of spec and pricing do you expect? Rumor I heard is that it'll have real sequential gearbox (rather than manual or PDK) which is rather pricey to run (if like one in GT3 Cup).
I'm curious to see what sort of Go-Fast parts it may have that can be retrofitted to the road car...
I'm curious to see what sort of Go-Fast parts it may have that can be retrofitted to the road car...
#5960
Burning Brakes
I like what I see but am waiting to hear some reviews from the usual suspects...If I were to be crazy enough to pursue this (my wife would probably kill me since I've only driven the GT3 3 times so far, it's winter here), mine would be Barney purple...
#5961
If you compare the price on a GT3 Cup vs GT3 and use the same ratio on the GT4 it'll be around $160k.
#5962
Burning Brakes
#5963
Burning Brakes
Adding the Crawford wing to my GT3 made that tail wagging go away coming into T17 at Sebring close to 150 MPH. It produces at least the same Downforce as the GT3RS Wing.
#5965
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I wonder if anyone saw this gem on the pca website...
"A pure race track version (of the Cayman GT4) will follow later in the year."
https://www.pca.org/news/2015-03-03/...ion-cayman-gt4
"A pure race track version (of the Cayman GT4) will follow later in the year."
https://www.pca.org/news/2015-03-03/...ion-cayman-gt4
#5966
Three Wheelin'
This video has the mistaken 9000k redline. So, at some point in development, it must have been 9k
#5968
These would be peak piston speeds based off the length of the stroke, 360 degrees of rotation & the max allowed revs per minute. In one full "stroke" an engine's piston must come to a full stop x2 times (once each at the top & bottom of the stroke) then accelerate/decelerate quickly enough to cover, I think, 2x the length of the stroke. As rpm increases, this puts bigger, and bigger stress on the parts.
Google something like "peak piston speed" and you will find stuff/threads like http://www.eng-tips.com/viewthread.cfm?qid=85349
where stories of mechanical failures are caused by excessive acceleration and deceleration forces.
I guess one question is, "Where did the additional 200cc come from? An increase in bore? Stroke? Or a bit of both?" My guess would be bore only, but that's just a guess in which case rpm would have been reduced to allow for (probably) slightly more mass in the pistons due to slightly larger size, but I'm just guessing. Or as others have suggested, maybe Porsche expects the "RS's" just to be driven harder by the more manly men & women who own them, and think they need a greater margin of safety to get the motors past their warranty periods.
Google something like "peak piston speed" and you will find stuff/threads like http://www.eng-tips.com/viewthread.cfm?qid=85349
where stories of mechanical failures are caused by excessive acceleration and deceleration forces.
I guess one question is, "Where did the additional 200cc come from? An increase in bore? Stroke? Or a bit of both?" My guess would be bore only, but that's just a guess in which case rpm would have been reduced to allow for (probably) slightly more mass in the pistons due to slightly larger size, but I'm just guessing. Or as others have suggested, maybe Porsche expects the "RS's" just to be driven harder by the more manly men & women who own them, and think they need a greater margin of safety to get the motors past their warranty periods.
Last edited by mlpor; 03-04-2015 at 12:01 PM.
#5969
GT4 Cup will be at least 991 GT3 money when compared to the competition. The Lotus Evora GT4 is GBP125k. I expect Porsche to charge a little more than GT3 money for the GT4 Cup - my money is on $160k.
I'll pm more details too
I'll pm more details too