because FF su*ks and FR is too mainstream for a sports car.
Two things wrong about this video. First, it’s rear engine because it was derived from the Volkswagen Beattle, not because the engine placement was an advantage. Porsche has worked for years to overcome the bad placement of the engine with huge rear tires and suspension tweaks. Years ago they were difficult to drive, if you let off the gas or braked in a corner it went from bad understeer to bad oversteer. Even now, if a Porsche goes off the road it goes off backwards. Porsche has continued with the design of the 911 because the customers want it. The 914, 928, 944 did not sell well even though they had better handling. Currently the Boxter and Cayman handle better than the 911 because they are mid-engine. The best designs for handling are either mid engine or front engine/rear transaxle with a 50/50 weight distribution. I would rather own/drive a Cayman than a 911.
There are two things wrong with this video: first, the engine is in the rear because it is derived from the Volkswagen Beatle, not because it is a good design. Porsche made several different cars, 914, 924/944, 928 that handle better than the 911 but they didn’t sell very well. Customers wanted the traditional look of the 911. The physics of the video is wrong as well. Porsche has worked on making the 911 handle decently over the years by adding huge rear tires and tweaks on the suspension. For many years, in a corner a 911 has extreme understeer but if you let off the gas or applied the brakes it went to extreme oversteer. If a Porsche leaves the road, it usually is going backwards. The Boxter and the Cayman handle a lot better than the 911 because they are mid-engine. The best design for handling is either mid-engine or front engine/rear transaxle because you can get a 50/50 weight distribution. I would rather own/drive a Cayman than a 911.
God, sorry Brian - I should have checked all the replies first - I almost rewrote part of your post (great minds think alike, I guess….Heh! :D)
And we both forgot to (explicitly) mention the lift-off/snap oversteer tendencies, due to engine braking if one lifts off in a corner, post understeer. Course this is also dependent on the gear you’re in and the road conditions as well, but it’s (bizarrely) a trait that can be found in some FRONT wheel drive cars, too.
The only reason the 911 was (and is) rear engined, is because the design layout was stolen from Tatra, after the Nazi’s plundered Czechoslovakia, Hitler charged Ferdinand Porsche to come up with the KDF Wagon (aka ‘People’s Car aka Volkswagon’, and Ferdinand stole the idea and design. No more, no less. And of course from that, the 911 eventually came into being. It’s not like a rear engine is exclusively a Porsche trait (see 924 + 944, 928, even the VW-Porsche 914, plus modern models such as the Boxster, Cayenne and Panamera etc. etc.) When it comes to braking, the percentages, numbers and reasoning in this video are horseshit. Efficient deceleration in a car is all about the front braking power - the rear brakes are just there to keep the arse end in check. Hell, you can even test this on a bicycle - brake from speed with the front brake only (without locking up) and then try the same thing with the rear brake applied only….and see what happens. In a car, the placement of the engine is partially negligible, because as a mass and therefore weight, it’s simply contributing to forward inertia and momentum (it’s contribution to mechanical braking via gearing and compression is something else). So while extra weight upon on the actual braking end of the car is a factor, it’s evened out by the horizontal mass effect. The fact is, it’s pretty much entirely (90-95%) of the front brakes in any car that do the stopping business,
I’ve never read so much buillshit in my life, you need to go and read some kinematics and dynamics books, Or hell, even look at a tyre load graph, The ONLY reason a bicylce uses a lot of front brake is because your weight is centred and the CoG is high compared to the wheelbase, loading the front wheel, if you sat your weight over the rear and down low ( a la 911), you’d find you’d require much less front brake, much more rear brake AND you’d stop slightly faster, because you’re loading the tyres much more evenly.
Comments
because FF su*ks and FR is too mainstream for a sports car.
Two things wrong about this video. First, it’s rear engine because it was derived from the Volkswagen Beattle, not because the engine placement was an advantage. Porsche has worked for years to overcome the bad placement of the engine with huge rear tires and suspension tweaks. Years ago they were difficult to drive, if you let off the gas or braked in a corner it went from bad understeer to bad oversteer. Even now, if a Porsche goes off the road it goes off backwards. Porsche has continued with the design of the 911 because the customers want it. The 914, 928, 944 did not sell well even though they had better handling. Currently the Boxter and Cayman handle better than the 911 because they are mid-engine. The best designs for handling are either mid engine or front engine/rear transaxle with a 50/50 weight distribution. I would rather own/drive a Cayman than a 911.
There are two things wrong with this video: first, the engine is in the rear because it is derived from the Volkswagen Beatle, not because it is a good design. Porsche made several different cars, 914, 924/944, 928 that handle better than the 911 but they didn’t sell very well. Customers wanted the traditional look of the 911. The physics of the video is wrong as well. Porsche has worked on making the 911 handle decently over the years by adding huge rear tires and tweaks on the suspension. For many years, in a corner a 911 has extreme understeer but if you let off the gas or applied the brakes it went to extreme oversteer. If a Porsche leaves the road, it usually is going backwards. The Boxter and the Cayman handle a lot better than the 911 because they are mid-engine. The best design for handling is either mid-engine or front engine/rear transaxle because you can get a 50/50 weight distribution. I would rather own/drive a Cayman than a 911.
God, sorry Brian - I should have checked all the replies first - I almost rewrote part of your post (great minds think alike, I guess….Heh! :D)
And we both forgot to (explicitly) mention the lift-off/snap oversteer tendencies, due to engine braking if one lifts off in a corner, post understeer. Course this is also dependent on the gear you’re in and the road conditions as well, but it’s (bizarrely) a trait that can be found in some FRONT wheel drive cars, too.
The only reason the 911 was (and is) rear engined, is because the design layout was stolen from Tatra, after the Nazi’s plundered Czechoslovakia, Hitler charged Ferdinand Porsche to come up with the KDF Wagon (aka ‘People’s Car aka Volkswagon’, and Ferdinand stole the idea and design.
No more, no less.
And of course from that, the 911 eventually came into being.
It’s not like a rear engine is exclusively a Porsche trait (see 924 + 944, 928, even the VW-Porsche 914, plus modern models such as the Boxster, Cayenne and Panamera etc. etc.)
When it comes to braking, the percentages, numbers and reasoning in this video are horseshit.
Efficient deceleration in a car is all about the front braking power - the rear brakes are just there to keep the arse end in check.
Hell, you can even test this on a bicycle - brake from speed with the front brake only (without locking up) and then try the same thing with the rear brake applied only….and see what happens.
In a car, the placement of the engine is partially negligible, because as a mass and therefore weight, it’s simply contributing to forward inertia and momentum (it’s contribution to mechanical braking via gearing and compression is something else).
So while extra weight upon on the actual braking end of the car is a factor, it’s evened out by the horizontal mass effect.
The fact is, it’s pretty much entirely (90-95%) of the front brakes in any car that do the stopping business,
I’ve never read so much buillshit in my life, you need to go and read some kinematics and dynamics books,
Or hell, even look at a tyre load graph, The ONLY reason a bicylce uses a lot of front brake is because your weight is centred and the CoG is high compared to the wheelbase, loading the front wheel, if you sat your weight over the rear and down low ( a la 911), you’d find you’d require much less front brake, much more rear brake AND you’d stop slightly faster, because you’re loading the tyres much more evenly.
Why Rear Engine?? Because GRIP!