Really stumped as to why Ferraris have some crap specs

I've whined before about kerb weights going up. This is somewhat more serious, I think.

I test drove an Alfa 164 recently (I love Alfas!) and was disappointed in the turning circle (most FWD cars are like that anyway). It wasn't that bad but geez, you take manoeuverability for granted in your own car until you try one less so. I just checked the Ferrari F355's turning circle. The Alfa's was 11.2m or something like that. The Ferrari's was 12m!! WTF? (EDIT: that's more than a Jag XJ). A front-driven car, with all its limitations, has a smaller turning circle than a smaller 2-seater?

Another thing I don't get: the 360 (and I think its successors) have a significantly off weight distribution ratio. It's about 42/58. And it's a mid-engined car for what? Even the Quattroporte is closer to 50/50. And BMWs are pretty damned close to ideal.

Now, okay, I don't own nice cars like Quattroportes, M3s or F355s. But this isn't armchair philosophizing. I mean, the turning circle issue is important if you're going to drive the damned thing on the road (like you're supposed to, because cars are not trophies).

So. What gives?

 

I personally couldn't give a stuff about the turning circle.
I can't imagine anyone asking that question in the showroom and being put off by it being 1m wider than some other car.
Strange as it may seem, no one is buying these sort of cars to go parking and shopping in. They are after many things including good vehicle dynamics, road holding etc and I would personally expect that the manufacturer whoever they are has done their homework and designed the vehicle with particular dimensions for a reason. If that means a wider turning circle because they have changed the wheelbase or made the track wider then so be it.

The Quattroporte is an entirely different car, its a four seater, if they decide to make its weight 50/50, then thats probably what they wanted. If the new 458 Italia is weighted at 42/58 or something similar, then I for one would still go and buy it like many here I'm sure. They have been designing cars for years, they obviously know what they are doing and still get the new cars around Fiorano quicker and quicker.
I'm sure that they can still park it in the pits afterwards with no problems.

 

There is a bigger concern to me.Government regs and luxury/electronic parts are overwhelming the engineers ability to build light weight vehicles.Can you imagine what lurks behind the bloated dash boards?

 

In the quest to provide more cockpit space, more luggage space, more of the latest electronic features, plus all the government mandated safety items, luxury "sportscars" have suffered. Then there are the secondary effects of the above such as the increased performance required because of the weight increase. Everyone should drive a true minimalist sportscar like a 1966 Lotus Elan once -- 120HP @ 1500lbs, turning circle 9.8m to get some perspective. And then there is what the customers want and will buy...

 

The Honda Odyssey has a turning circle of 5.58m and can seat 7!!!

Aaron

 

Bingo! its the way of the world today... everything is being driven by marketing people who only want more bling, bells, whistles and comfort than their competition at the sake of the core product. But, if you want to sell more cars you have to build something that is more suited to Joe Public or worse, Joe Gotmoneyandnopassion. I personally applauded BMW's resistance to cupholders! (yes, I know, they finally caved in). I have one (cupholder) in my other cars but don't have nor need one in the Ferrari. Yeah, a lot of today's cars will outperform yesterdays cars. But think how much better (sportscars) they could be... if the 458 had been built with F40 creature comforts in mind?? <sigh>

Rick

 

Well you could be on to something with weight distributions and other issues I've not thought about. but I will tell you what I see and what I have experienced. There is no doubt that the 458 430 360 355 348 in that order are amazingly fast for their day around the ferrari test track with their pro drivers. I'm certainly no pro but I have been roadracing for years and have 2 race licenses and do casual trackdays too just for tracktime. For some reason I see people in ferraris on average slower than people in what would have been a competative car. 90% of the time I see people jump in a vette or porker and be instantly comfortable and drive fast. No so in a ferrari. Ferraris seem to be a handful at speed. Yesterday there was a guy testing and practicing in his 360GT full decked out racecar airjacks and all. He was fast but he carrys just over 5lbs/hp! I watched as a guy in driven to the track bone stock C6Z06 (6lbs/hp) filled his mirrors for a whole session. Its typical of what I see when the power to weight gets close to XYZ ferrari you can usually beat it. I don't know what that means but that's what I witness. The 348 was a hot car in 1990. When I raced my 348 years ago I was surprised by how hard it was to go fast. Quite frankly it was easier to go fast in a late 80's 944 or 928. I don't know why.

 

Except Lotus builds the 2010 Elise/Exige, which are ~2000lbs, and the 2010 Porsche Boxster Spyder skates in at 2866lbs.

That's about 1000lbs less than the bloatmobile Ferrari 599.

I think Ferrari fell into the trap a while ago of adding weight in order to add luxury in order to justify charging a premium for their cars.

 

If you don't like the turning circle diameter, drop it into first gear and give it a big dose of throttle. I can, personally, get my F355 to turn in just about 2 body lengths.

This is a very well understood anomoly. Weight distribution should definately NOT be 50%/50% unless the rear tires are the same size as the front tires. With high powred cars, it is almost NEVER the case that the rear tires are the same width as the front tires.

If you take the front/rear weights and compare them to the tire footprint, you want the rear tire footprint to be slightly bigger than the relative weight it carries. This gives the gently understeer under maintanence-throttle max cornering conditions.

With the weight distribution closer to 45%/55% one would want a 225 front tire and a 275 rear tire--notice that these are almost the exact F355 tire specifications. When you get down to brass tacks, the suspension geometry comes into play and alters (slightly) the tire size versus weight distributions; and to an even lesser extent, chassis tortional stiffness.

But the thing to remember is that 50%/50% weight distribution is for cars with the SAME tire sizes all round.

 

Having a 50/50 street mid engine rear car oversteer into a spin... I rather have it like they are now or like in a Porsche 911.

 

Well, here's my take on it:

Turning radius is often limited by steering geometry, and the placement of the tie rods affects bump steer, steering feel, and stability. I prefer the geometry be designed with the steering feel and control as number one, not the turning radius. My Cobra steering is fantastic, but rack placement to get it that way severely limits turning radius, which is more like a city block. But I sure wouldn't trade it, the steering is soooo sweet. The wife's Odyssey will turn around in a parking spot, but I am willing to make compromises in that car. I have never felt the 355 to have a particularly big turning circle to be honest - seems just fine.

Weight distribution should definitely NOT be 50/50. That is some sort of marketing crap, and I have not understood why people buy into it. The Lotus Exige S is 38/62, and it is one of the best handling cars out there. F1 cars are something like 30/70. You want significantly more weight on the rear. When you step on the gas, the weight shifts rear ward and keeps the tires planted for maximum acceleration. When you nail the brakes, the weight shifts forward and the extra rear weight allows all four wheels to stop the car, not just the fronts.

In a turn, physics helps balance things. Remember that grip is related to the force down on that tire. So with the same coefficient of friction, there is more grip from the tires with more weight on them. But those tires also have to move more weight, because that part of the car is heavier, so it actually balances itself out naturally. It then comes down to subtle things like suspension geometry, spring and shock function, antisway bars, and the such.

The midengine placement is not for weight distribution, it is to reduce the polar moment of inertia. Like an ice skater pulling in to speed a spin, keeping the mass central means you can rotate (or stop the rotation) of the car quicker.

Look at the older 911s. They are known for snap oversteer. Must be because all that weight on the back wheels, right? I don't think so. Want to keep an axle planted, put weight on it. I think it is more that there is a big motor like a pendulum sticking out of the back of the car. So once it starts rotating, it is really hard to stop it from rotating, and the thing just keeps coming around. Which is why a pro can really have there way with the car, but an inexperienced driver can be caught out.

 

Exactly...

Here one.. I have a 1985 Lotus Esprit Turbo with a 225hp/240tq turbo motor on a 2300lb chassis. I happened upon a highway stop light next to a 2008 Mustang Shelby GT500 recently and thought I would be slayed if I dared race him.. but tried anyways Of course I did loose, but wasnt beat as bad as expected.. At the time I wondered why a car, 23 years newer, with almost twice the hp wasnt that much quicker... I no idea it weighed 4000#!! ..geez.. it needs 500hp!!

Two other cars which I would highly recommend everyone test drive in anger is the Lotus Elise/ Exige and the Caterham hyabusa super seven.. those are 1966 Elans on steroids!!..and two of the most fun cars I have ever driven..

 

the short answer to the 911s problem is that the weight is behind the axel. not above it or in front of it. So like throwing a hammer... its a bit wobley. an Audi A4 is the same... its engine is way out infront of the front axel.... good luck not getting understeer in that car

 

There it is, kind of suprised it took that long to get said.

 

Exactly! 50/50 weight distribution is often a marketing ploy and is often only achieved by putting a battery way out over the rear wheels of a front engined car giving both ends of the car a lot of weight at the sacrifice of the polar moment of inertia.

For future reference when trying to ascertain what the 'true' performance specs for a road car should be start with an F1 car and work your way down from there. There is a reason way F1 cars don't have a perfect 50/50 weight balance. I remember getting in an argument with a friend of mine a couple of years ago (who was into Hondas and all that crap at the time) over what was the true performance platform; a front wheeled drive car versus a rear wheel drive car. I just told him to tune into SPEED TV early on a Sunday morning for the answer and walked away.

 

So, you want more responsive steering and road feel and a smaller lock-to-lock for faster reaction BUT you also want a tighter turning radius.

I suggest you complain to Sir Issac Newton. Darn him for creating those pesky laws of physics we are all bound to.

 

I don't agree with you guys. You can't compare an F1 design with pro drivers and a streetcar with john q Iwanna go fast. I don't think you can take weight distributions and polar moments out of context. It is the "package" that makes a car fast. If this was no true you would be able to design the perfect car on paper and win. But the facts are that designs on paper are proven on track and sometimes they fail miserably.

Back to streetcars my 348 was stock weight balance and was a more forgiving ride closer to stock 42/58 or whatever. When gutted for racing I was 40/60 at 2800lbs with me in the car and 1/2 tank of gas on slicks. Everything said about rear weight bias is true except once you broke traction and started to spin the light front end reduced your chance of catching the car by counter steer and once you got to a certain point is spun really fast and out of control because the weight was in the back like the hammer analogy. I found you had to tune the chassis to get just a mild oversteer but could never cure the snap oversteer that would come on occasion if I was not careful. The result was a more tentative slower driver. I'm no expert just an SCCA racer. Now when I race my Z06 with is near 52/48 and all 4 tires the same size barely any chassis tuning off stock and I can get some mild oversteer and no snap. If the car spins the front has more weight on the tires and counter steer is much easier. Because there is less weight in the back the polar moment hammer effect is not there and my front counter steer is more effective. If the car does spin from my own stupidity because the weight is in the front the spins are slower and more gentle with much greater chance of recovery and getting pointed back in the right direction to get back in the race. The Z06 is like a dumbell front engine rear transaxle yet the center of rotation is more centralized and works pretty much as if the weight were central. The result I'm faster as a club racer. This supports what I see on even casual trackdays which is a guy in a random porsche or vette or viper will be faster than a Ferrari 9 times out of 10. Anyway, try it for yourself. Don't be surprised if you show up at the track in your own 360 and try a friends C5Z06 for the first time you ever drive the thing and are faster in the vette.

 

That's what I meant with my short post and I thought most guys here knew this, what was it, coriolis effect?

 

I had an F355 and was inconvenienced by the turning radius. It took seesawing back and forth to get into a tight turn into the garage. It took a wide swing for a big circle to hit the driveway. But... it was nothing compared to a 512M I had for a short time at the same time. That thing was not even enjoyable because of the ridiculous turning radius. I didn't notice it at speed on the roads and highways, but it was annoying around town. Trading the F355 for a 550 Maranello, kept at the same time as the 512M, and Ferrari had gotten their sense back. I immediately compared the two and the 550 was a dream to drive anywhere compared to the 512M. You can compare mini-vans to sports cars all you want and wink, but when the sports car is actually a chore to drive, something's wrong.

As has been said above eloquently and intelligently, the "static" weight distribution is not important, other than a starting point for what is important. "Dynamic" weight distribution is. Biased to the back helps acceleration and a rear-heavy car is at an advantage even before the weight shifts (if it's rear wheel drive). In braking, a rear-heavy car shifts its weight forward and the dynamic effect is ideally 50-50 distribution in action. This lets all 4 wheels share the braking equally. Oh well, I guess I can't say it any better than it's already been said.

I always wondered with the 512M if Ferrari chose to not let the steering wheel turn enough to have a decent turning radius was because they were afraid it might go into a spin too easily or if maybe the front wheels would intrude into the interior too much if they turned further. Just thoughts, not facts, and it was a long time ago.

 

That's exactly what it is though

 

It's us just getting old, lol.

 

The whole deal about 50/50 wt. distribution started in the late 80s with BMWs introduction of the E34. Earlier 5s (and 7s for that matter) were notoriously "light in the rear", and BMW addressed this by making the E34 50/50. They heavily marketed this feature, and other companies began to follow suit.

Whether 50/50 is "ideal" is debatable, as many have pointed out. For the 5-series it was a huge improvement though.

 

Early 80's Porsche 944 are 50/50.

 

Yup. But the 944 is not your average front engined 80s car being that it has the transaxle in the rear (very unique). For most 80's front engined cars, getting to 50/50 was quite an achievement, and thus the marketing departments highlighted that (as has been pointed out above) as a major performance advantage.

While for performance purposes, most folks like a little more weight in the rear, most manufacturers aim for 50/50 or thereabouts, the goal being to not end up with a significantly oversteering car. The safety nannies dictate some understeer rather than oversteer. A bit of understeer, combined with ABS was the "safe" configuration for sedans and regular commuter cars for a long time. Now we have active suspension and active four wheel drift control being built into production sports cars so things are starting to change somewhat.

Me personally, leave everything off except the ABS and power windows please.....

 

A lesser car can easily have more steering response at parking lot speeds. Lesser cars easily have a short turning radius. However, stability at speed calls for very slow steering. Most Ferraris can easily travel beyond 150 MPH, slow steering is required.