Comparison tests Porsche 918 vs McLaren P1 vs LaFerrari
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Ok maybe you can explain how Autocar got 0-180mph in 18.2sec in the 918 test which was only 0.2sec (eye blink and a close shave) slower than the P1 achieved in its road test? And also C/D got 17.5sec to the same speed? So that fact of front electric motor disengaging at 165mph doesn't really have an adverse effect on its acceleration at higher speeds. The aerodynamics of the P1 could be more adversely affected at higher speed than the 918 so it's rate of acceleration could be compromised due to higher down force and higher drag coefficient
treynor
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Depending on how they tested, the P1 does not have enough traction for full power until between 70-85 mph. So I suspect 0-80 is faster for the 918 and 80-180 is faster for the P1. I see a marked acceleration advantage for the P1 at higher speeds in the telemetry.
Different conditions in all 3 tests. You can see from the 160-170mph time for the Autocar P1 vs 918 that the P1 was against the wind. How else would it be slower over that interval given the 130hp loss at 165mph for the 918?
Of course it does, how would losing 130hp not affect acceleration. The P1 has DRS, so the drag isn't that high at all, and it has the small matter of a full 903hp.
Over on McLife I remember an owner of both saying that the P1 was 0.5s quicker from 60-130mph.
Wind wasn't a factor during the Autocar tests at MIRA because they run both into and with the wind and take an average. Emu will try and deny this but it is a fact and it is how Autocar carry out all of their formal performance tests.
The reason why the 918 was so slow 0-200mph (~29s) during the Autocar test at Bruntingthorpe (apart from the engine decoupling) is because Autocar didn't know how to stall the rear wing. As Chris Harris showed in his car of the year video this can be done by switching from Race hybrid to Sport Hybrid.
The reason why the 918 was so slow 0-200mph (~29s) during the Autocar test at Bruntingthorpe (apart from the engine decoupling) is because Autocar didn't know how to stall the rear wing. As Chris Harris showed in his car of the year video this can be done by switching from Race hybrid to Sport Hybrid.
That's the only possible explanation for the 918 being faster 160-170mph. Side winds will screw thinks up either way, as would rain. The also tested it in Race Mode. You can see the difference with the MT figures.
http://www.germancarforum.com/threads/autocar-road-test-mclaren-p1.50685/
http://www.motortrend.com/roadtests..._motor_trend_production_car_record/specs.html
That's not the reason at all. The 918 is just way slower after 165mph because it only has 750hp and weighs 1640-1675kg vs 903hp and 1500kg. Really simple facts here. Surely the wing would stall itself in a straight line like the P1's does anyway?
If you still think a 750hp car weighing 1640+kg can get to 200mph in 25-26s, what can I say but you're very badly deluded. Never been done.
Ladies and gentleman. I present to you the Porsche 918. It makes miracles happen.
I make that 0-200mph in about 23s. Without Hot Lap mode.
Now kindly explain how the P1 generates 2.6g tangential to road surface through the Karussell. I'm intrigued to hear your nonsensical explanation, if you have one.
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Conditions, wind, gradient etc. Clearly if the P1 had ran along side it, it would have been 6s faster, as suggested by another result saying 'just over 20s' for 0-200mph.
Without hot lap mode? And you wonder why nobody listens to German magazines when it comes to Porsches? Frankly I wouldn't be surprised if it created a wormhole through space-time in a German test.
http://www.caranddriver.com/feature...re-performance-data-and-complete-specs-page-2
http://www.motortrend.com/roadtests..._motor_trend_production_car_record/specs.html
60-150mph
918 - 8.3s
P1 - 7.3s
4mph quicker in quarter mile despite RWD.
So 1s faster from 60-150mph with a neutral country testing and the 918 loses 130hp above 165mph and the 918 tops out at 213mph, the P1 is electronically limited to 217mph, 205mph on Dottinger vs 196mph for 918 (even though that was the same BS test as above).
Side-by-side:
Level at 60kph
16kph lead at 220kph
Treynor has also already stated that the ideal lap time for both cars, comprised of the best sector times, was about the same (to with hundredths). He has also stated that the 918 had more grip on corners and it obviously has more traction on the way out of low speed corners, as well as more grip under braking at low speeds. So where do you suppose the P1 made the time back if not on the straights?
Maybe it's composite g, i.e. a vector sum of longitudinal, lateral, normal gravitational and roll. It doesn't specifically say 'lateral g'.
You've also got mgsin(angle) opposing (mv^2/r)cos(angle) as well as friction. What angle is the Karussell?
So resolving parallel and perpendicular to surface:
Grip, tyres + mgsin(angle) = (mv^2/r)cos(angle)
N = mgcos(angle) + (mv^2/r)sin(angle)
Grip = uN (where u = coefficient of friction.
So you have a strange situation where N is actually increased by the lateral acceleration.
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Emu weight and power are not the only factors affecting acceleration ability, torque (918 has 30% more torque than P1), gear ratios, friction factors for power train, road and aerodynamics are also a factor especially at high speeds. In fact at high speeds the power and aerodynamics is more of a factor than weight. If you talking about acceleration at higher speeds with lower power as well as top speed, then I am sure you will know about the old master McLaren F1, it has only 627hp (against 916hp) but it has a top speed of 391km/h against the limited 350km/h for the P1, the F1 was gear limited to that speed as well. There is a possibility that at speeds higher than 335km/h the F1 will start overtaking the P1.
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Show us where you get 205mph on the Dottinger Hohe for the P1. The 196mph is what AS driver Horst von Saurma achieved but his time was 16sec slower than what the Porsche test driver Marc Lieb achieved on the production car record run, so obviously he ran a much higher speed on the Dottinger Hohe.
Conditions, wind, gradient etc. Clearly if the P1 had ran along side it, it would have been 6s faster, as suggested by another result saying 'just over 20s' for 0-200mph.
Without hot lap mode? And you wonder why nobody listens to German magazines when it comes to Porsches? Frankly I wouldn't be surprised if it created a wormhole through space-time in a German test.
http://www.caranddriver.com/feature...re-performance-data-and-complete-specs-page-2
http://www.motortrend.com/roadtests..._motor_trend_production_car_record/specs.html
60-150mph
918 - 8.3s
P1 - 7.3s
4mph quicker in quarter mile despite RWD.
So 1s faster from 60-150mph with a neutral country testing and the 918 loses 130hp above 165mph and the 918 tops out at 213mph, the P1 is electronically limited to 217mph, 205mph on Dottinger vs 196mph for 918 (even though that was the same BS test as above).
Side-by-side:
Level at 60kph
16kph lead at 220kph
Treynor has also already stated that the ideal lap time for both cars, comprised of the best sector times, was about the same (to with hundredths). He has also stated that the 918 had more grip on corners and it obviously has more traction on the way out of low speed corners, as well as more grip under braking at low speeds. So where do you suppose the P1 made the time back if not on the straights?
Maybe it's composite g, i.e. a vector sum of longitudinal, lateral, normal gravitational and roll. It doesn't specifically say 'lateral g'.
You've also got mgsin(angle) opposing (mv^2/r)cos(angle) as well as friction. What angle is the Karussell?
So resolving parallel and perpendicular to surface:
Grip, tyres + mgsin(angle) = (mv^2/r)cos(angle)
N = mgcos(angle) + (mv^2/r)sin(angle)
Grip = uN (where u = coefficient of friction.
So you have a strange situation where N is actually increased by the lateral acceleration.
The usual mix of irrelevant nonsense, false equivocations and outright BS that we've come to expect from you Emu. I tip my hat.
The point being made was that Autocar ran the 918 at Bruntingthorpe in race hybrid when it should have been in sport hybrid. As far as I'm aware Bruntingthorpe is the only same day race performed between the two cars but unfortunately the result is void.
So going back to Karussell. It has a banking of 30deg and according to McLaren
"In terms of pure lateral g-forces, the driver is subjected to 3.9g" -
http://media.mclarenautomotive.com/release/233/
Please explain how this is possible.
That only has an effect in the lower gears. In the higher gears the P1 has sufficiently tight ratios for it not to matter and it actually has a fairly broad power peak, lasting for over 1000rpm around peak power.
The 918 is no F1. The F1 only weighed 1138kg. The P1 is 1.3s and 11mph faster over the quarter.
This is all hypothetical though because the 918 can't do anymore than 213mph. Therefore the P1 has more surplus power all the way.
No they didn't, that's just you making excuses, you have no official source. It was in HL mode as SS confirmed.
I think I just have at the end of the post you quoted if you actually read it and tried understanding it.
Grip, tyres + mgsin(angle) = (mv^2/r)cos(angle)
N = mgcos(angle) + (mv^2/r)sin(angle)
Grip = uN (where u = coefficient of friction.
uN + mgsin(angle) = (mv^2/r)cos(angle)
N = m[gcos(angle) + (v^2/r)sin(angle)]
N = 1500 * [(9.8 * 0.866) + (v^2/2r)]
So:
1500u[(9.8 * 0.866) + (v^2/2r)] + mg/2 = (1500v^2/r)*0.866
-> u[(9.8 * 0.866) + (v^2/2r)] + mg/2 = (0.866v^2/r)
Hopefully you can see that grip is actually increased because of the centripetal acceleration and also that lateral acceleration aided by the weight of the car.
Or in layman's terms, a solid immovable object, aka the ground, is largely responsible for the turning.
As I also stated above, I can't be sure this is just lateral g or a vector sum of all g that's being stated.
http://www.topgear.com/uk/car-news/mclaren-p1-nurburgring-lap-time-video-2013-12-05?imageNo=1
I think a customer made 202mph over on McLife. He lifted for the corner to avoid taking out a 1 series.
In fact, you've stumbled on something quite nice here. This is his 324kph run lifting off near end for traffic.
Mclaren P1
Being quite generous with start of straight - 0:23.
End of straight - 0:44.
Porsche 918
Start of straight (much nearer here) - 7:13.
End of straight - 7:37.
So basically an amateur driver (Michael Benham - MikeyB?) in a customer P1 is >3s faster than Marc Lieb between the bridges on the main straight whilst lifting off for traffic. We know that the official/unofficial/pro P1 lap achieved 6kph more on Dottinger Hohe. Assuming that to be the average speed delta (when in reality it will be more because acceleration slows at high speed), we know that Chris Goodwin was 4s faster between the bridges alone. 4s being about 360m at this speed.
So it does. I guess they don't realise that what's lateral to the driver isn't actually lateral anymore.
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