Porsche 911 - Terrible Design, Perfectly Executed

[Deeks]

following on from a discussion about the pros and cons of 911 v 944 ownership, a 944 owner suggested this as one of many reasons to go for the front engined watercooled philosophy......

is it really true ?

[Milu]

Having owned 911s and 944s and a 924turbo, and covered a lot of miles in all of them, I would suggest that the water cooled cars are much easier to drive and make for a more relaxed and practical daily driver. A 911 takes longer to learn and appreciate, but once you understand them you reach a higher level of comprehension and what appears a vice to a 944 driver is a virtue to the 911 afficionado.

[cegerer]

"is it really true ?"

No.

[dickster]

terrible design and a porsche 911

thats a bit of a contradiction!

deeks, have you driven either?

if not go and try both. they are totally different animals. you'll see what i mean. just don't expect the 911 to be easy to drive - its not - then you'll probably love it.

and thats what matters (to me anyway)

[911jon]

Deeks,

It is a matter of education. This statement is something of a motoring journalist cliche, often propounded by ill-informed and ignorant writers with a minimal understanding of engineering and design.

"Design" is a broad term, but if you consider the car from an industrial transportation design stance the car is beautiful; visually striking (highly sculptured), wonderfully packaged (this is often overlooked) and instantly recognisable. The ergonomics of older 911's are undoubtedly flawed, but you must remember how old the basic cabin design is! It has fared remarkably well.

In terms of pure engineering principles you can argue that it is flawed, in that the ideal location for the engine is in front of the rear wheels, minimising the polar moment of inertia of the car, rather than behind. But the actual weight distibution is not far from ideal race practice due to the forward mounted transmission.

This layout simply requires driver education to master - it is quite different to a front engined car. An unskilled driver with front engine only driving experience may well crash a 911 when trying to drive fast; and then blame the car for their own shortcomings!

Ignore BMW's claims, race cars are not 50/50, or front engined.

As a driving experience it is extremely pleasurable for a skilled operative; remember that most cars are "dumbed-down", i.e. tailored for poor/mediocre driving skill, safety first. 911's are attitude controllable with the throttle and are extrememly sensitive to driver input, convincing many that they are dangerous to drive.
This is not so; but they do require skill and concentration and reward these with a driving experience second to none.

So is the 911 a poor design? Absolutely not. It is one of the very finest vehicle designs in the history of the motor car, and is widely considered an icon of industrial design.


Just my view... rant over...

[jluetjen]

Having owned both, I would like to propose a rephrase of the opening line. "The 911 is a more demanding design then the 924/944's, but both are excellently executed."

The 924/944's have wonderfully smooth tossable handling and gentle charactoristics at the limit. Both of these are the result of the long polar moment created by having the engine at one extreme and the transaxle at the other. The 50/50 static weight distribution is handy because given equal tire and wheel sizes at each end, the car starts out being equally demanding of each corner. (Please note that when a car is being driven though, nothing is static. This is why 944's still respond well to larger tires in the back.) In summary a comparatively easy car to drive quickly.

The 911 on the other hand quickly developed into a car that can be driven REALLY fast by skilled drivers. Having the engine in the back is often described as throwing a dart backwards -- it's just dying to flip around. In reality if you ask any race driver, one of the key components of confidence in a car is corner entry turn-in. Nobody likes a car that pushes. They want a car that is twitchy on turn-in. It is hard to get this with a 924/944 because the long polor moment resists sudden changes in direction. By nature a 911 turns into corners. Because of the weight in the back a 911 does have ultimate oversteer, but this is easily managed by a driver who knows how to manage the a car's balance using the brake and gas pedals. BTW; a 911's handling is more akin to a rear-midengined formula car then a 924/944's. If you can drive a 911, you will be comfortable in Formula car and vice versa.

The second big factor for the 911 is the engine. While compared to modern racing motors, it's air-cooling limits ultimate HP, direct from the factory its spec's are much closer to a race car motor then a 924/944's. It also has a number of nice "homologation" features that make it easier to get HP from a 911 motor then a 924/944 (when comparing N/A to N/A and Turbo to Turbo). A couple of "for examples":

1) 911's have big valves straight from the factory which leave room for easy HP. 8-Valve 944's on the other hand are limited by their valve sizes to about 165-185 HP. This is why Porsche had to go to turbos or 4-valve heads to get more HP from that engine. For comparison, the valves of 2.2 liter 911S engines can flow enough air to generate 210-250 HP without touching the heads! The non-S 911's had the same size valves, but require a little bit of porting. Speaking of porting, I've never heard of anyone hitting a water passage while porting a 911 head.

2) 911 drivelines are an excercise in metalurgy in order to keep the weight down. They have magnesium all over the place. This improves the lb/hp ratio as well as the handling -- especially in the early cars (Sorry SCWDP!).

3) 911 engines come from the factory dry-sumped. This reduces windage losses in the crank-case which frees up HP. They also can corner all day at the limit without seizing a bearing, something that 944's can't do with confidence.

4) The Boxer-6 arrangement of the 911 motor is naturally balanced. So 5HP does not have to be wasted on balance shafts. Nor are special engine mounts required.

And then there is the extra weight of water cooling a 924/944, The absence of heat in the drivers compartment during racing situations from having the engine in the back, The "Straight-shot" intake shape on MFI'd and Carb'd 911's, etc. etc. etc.

They both are great cars compared to most of what the world has to offer. In both cases the execution resulted in successful compromises for the shortcomings of each design. But they were designed in different eras with different people in mind and their features reflect this. But at the end of day, Steve McQueen drove only 2 cars during the movie LeMans -- a 911 and a couple of 917's. I doubt that I'll ever be able to afford a 917, but I could afford a 911 .

[diverdan]

About 30 some years ago when Porsches were rear engined cars and I was in the Alfa Romeo camp, one of my Alfisti friend's asked a respected Alfa and sports car guru this question. "How would you compare Alfa's handling to that of a Porsche."

The answer was something like, "The Porsche is expertly engineered by Germans while the Alfa is splendidly crafted by Italians. Germans and Italians both like to drive very fast. However, the Germans think, the 'Dagos"...don't."

Diverdan

[rvanderpyl]

My wife has a 944, I have a 911. If I was going on a long trip I'd take the 944, you can cruise all day in it and arrive as fresh as when you left, the 911 is to rough for that (of course it's a 68, later models are more 'refined').

On the other hand when I drive the 911 it feels like it is an extension of my body, it seems to literally go where I think it. The 944 handle great as well, it just doesn't seem to have that razer edged response that the 911 does.

As for the swapping ends legends, I think a lot of that had to do with the technology, or lack there-of, of the tires that these cars came with when they were new. My cars standard tire when it was sold was a 165-15 on a 5.5x15" wheel, I now have 225-16-45 and 205-16-50's on the car, believe me it is pretty much impossible to swap ends with that combo, and I've tried all the no-no's of driving a 911 the last auto cross I was at, taking my foot of the gas when the tail is already light, even hitting the brakes hard while turning in hard, at no time did the rear end come out in a manner that I couldn't easily catch.

And maybe that is the other reason for the legend, when the 911 came out the other cars available at the time were mainly front engined and again undertired by our standards, so their ultimate handling limit was to plow straight ahead in a corner, easy to catch, just take your foot off the gas and wait to slow down.

Maybe you just needed to grow up driving in snow and ice where it was easy to get the rear end out to learn to love it.

[rcwaldo]

In my experience with open wheel racecars, normal "balance" for weight as well as aero balance is around 40/60%. 60% percent of course being rear.

Chris

[Deeks]

I've driven a 3.2 Carrera once before, but never a 944, though I grew up on a staple diet of aircooled rear-engined cars in the form of stock and highly tuned Beetles (which I know handle differently to 911's, but are related by blood and live life by the same philosophy). Personally I diasgree with the comment (why do all true race cars have engines positioned behind the driver ?), but I thought I'd throw a bone in the air and see what you guys had to say....

Jon. Excuse the naivety, but what do you mean by 911's having magnesium drivelines ???

Oh..... funny quote Diverdan !!...... LOL.

[Milu]

Originally posted by diverdan
About 30 some years ago when Porsches were rear engined cars and I was in the Alfa Romeo camp, one of my Alfisti friend's asked a respected Alfa and sports car guru this question. "How would you compare Alfa's handling to that of a Porsche."

The answer was something like, "The Porsche is expertly engineered by Germans while the Alfa is splendidly crafted by Italians. Germans and Italians both like to drive very fast. However, the Germans think, the 'Dagos"...don't."

Diverdan

Interesting. I cut my driving teeth on old Alfas of that time and I find there are a lot of similarities with old Porsches as far as handling and roadholding go. The Porsches have all the weight at the back and the Alfas have it all at the front, they are different but to me they have a similar flavour and I think If you enjoy one you'll also like the other. If Alfa had continued developing the 105 series and Fiat hadn't bought them I think they would have ended up with a real 911 alternative. (subject to Alfa build and quality standards of the mid 70s of course)

[jluetjen]

Deeks;
Regarding the "Magnesium Drivelines" depending on vintage street 911's have Magnesium...
- Transaxle cases
- Engine crank-cases
- Valve covers (they're as light as plastic!)
- chain housing covers
- Oil-pump housings
- intake manifolds(?)

In the case of the transaxles, Magnesium versions are about 20 +/- lbs lighter then comparable aluminum versions. I believe that the savings is comparable with the engine crankcases.

[speeder]

The cliche is that 911's are the ultimate example of engineering triumphing over design,(engine behind rear wheels is not exactly the optimum place, but they made it work, doggonit).

Many posters seem to be convieniently substituting aesthetics for mechanical design, when the quote clearly refers to the later. In terms of aesthetics, the 911 is widely considered to be one of the, if not THE best auto design of the 20th century, strictly from a styling standpoint. But that is not what was meant, of course.

This is much ado about nothing, old topic that has been beaten to death before I was born, (w/356), 911's have already won every popularity contest ever entered, and 944's lost theirs, with the buying public and collectors saying, "yawn".

[Kurt B]

Who said "terrible design" No one reputable did. I believe the general belief is it's a an imperfect design perfectly executed.