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After some more digging, I found specific information relating to the steering ratio of the smart's manual and electric power steering systems.

The manual system has a ratio of 22:1 (meaning one degree of rotation at the front wheels requires 22 degrees rotation of the steering wheel). The EPS system has a ratio of 21:1. So technically it is quicker, but by a very small margin.

Here are the theoretical steering inputs (i.e. steering wheel rotation) required to execute a 30 ft radius turn in each case, with the MINI Cooper thrown in for comparison:

Car......................................Wheelbase.......Ratio.......Steering Input
smart with manual steering...........73.5 in..........22.0:1........254 degrees
smart with EPS...........................73.5 in..........21.0:1........242 degrees
MINI Cooper...............................97.1 in..........13.2:1........199 degrees

This is a crude comparison that does not account for speed, steering geometry or tire slip angles, but it gives a clue as to why the MINI feels more agile.

I think the real world difference between smarts with and without EPS on the same tires will be minimal. I also suspect that the improved agility noted by some jounalists for smarts fitted with EPS may have more to do with bigger tires and reduced slip angles than the steering system itself.

The article referencing the steering ratio information can be found here (it contains some other interesting technical info too): http://www.duemotori.com/news/auto_news/10741_The_new_smart_fortwo_more_power_and_more_driving_fun.php
 

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Car......................................Wheelbase.......Ratio.......Steering Input
smart with manual steering...........73.5 in..........22.0:1........254 degrees
smart with EPS...........................73.5 in..........21.0:1........242 degrees
MINI Cooper...............................97.1 in..........13.2:1........199 degrees

QUOTE]


The Smart does feel like steering a truck compared with the MINI, and maybe that's why I wasn't too excited about the handling. Maybe an improved power steering unit with a radically reduced ratio would turn the Smart into what it really could be: a modern replacement for the classic Mini. The new MINI is too much of a pig to fit that bill.
 

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I think the steering cannot be too quick on the Smart because of stablity control issues with such a short wheelbase and tall body. Safety is the reason I think the Smartcar will always be less agile than the squat Mini. The Mini I think of as a cut and thruster and the Smart more as a relaxed cruiser.

All the euro car reviews on the new models mention that the power steering really helps though so there must be something to it. Perhaps just being able to turn the wheel easier gives the feeling of more agility since the ratio will always have be quite ponderous for the stability control system not to be constantly cutting in?

Sure would be nice to have a showroom full of Smarts to test drive both back to back! Well I can dream. :)
 

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That was TERRIBLE!

While that clip was pretty funny it is a little disturbing. First thing I do will be a set of high performance tires.
And a beefing up of the sway bars may help alittle bit, too. But the tires in a situation like that can make all the difference.
 

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And a beefing up of the sway bars may help alittle bit, too. But the tires in a situation like that can make all the difference.
Different tires would likely help, but a little piece of motor racing practice is this: in wet weather suspensions are SOFTENED-UP, not stiffened-up. A stiff suspension transfers too much weight to the outside tires and the result is excessive oversteer.

BTW, a person at the road show I attended had a "Brabus-ized" G&W 450. He admitted that the fatter tires cost him 10%-15% of his gas mileage.
 

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I think that buyers of the Smart are not really performance oriented and what with the height and short length stability issues perfer to have the safety margin of slow steering. In fact the Euro journals describe the stability control system in the Smarts program as brutal to keep it stable. For the small group of performance oriented folks there's always Brabus mods.
 

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Agree but disagree

Different tires would likely help, but a little piece of motor racing practice is this: in wet weather suspensions are SOFTENED-UP, not stiffened-up. A stiff suspension transfers too much weight to the outside tires and the result is excessive oversteer.
Agreed, fishrdnc, but we're talking about a race car suspension that is already VERY STIFF and taking away alittle bit of that stiffness to make it just stiff. On the other hand with the Smart, I'm convinced by watching the video that it is VERY SOFT and shows obvious tendency to understeer. So the suspension's conditions (race car compared to Smart) are at opposite ends of the spectrum you might say. I wonder if the rear end setup in the Smart has any sway provisions of any kind and what does the front suspension have. In the video, the car was very *loose* into the turn, not being able to handle the turn radius at the speed it was going.....leaning alot.....trying to straighten out the curve....that's understeer at it's worst. And better tires doesn't mean wider tread....as mentioned, that will take away mileage and also decrease traction as there is higher weight distribution at the rear wheels due to adding width to the traction tire. The 55 series aspect ratio radials that come on it should be good but the jury is still out on that one.....Simply adding a better quality rain tire would enhance the stickiness on wet roads like the Nokian NRV or similar tire.
JMHO :D
 

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Agreed as well

I don't think that clip is funny at all.
Ihoboy,
Not sure what's going on with posting on here. I just put a post entitled *Agreed but disagree* countering fishrdnc's post and it is not here now and I am not sure where it went.
Anyway, I agree with you. The video shows way too much lean and understeer and terrible control in the curve. I wonder what tires were on the car there.....not the 55 aspect ration tires the USA Smarts are coming with I don't think. It appears to have inadequate sway provisions, doesn't it? Did you notice how much it begins to sway just as it is coming into the hammer head part of the course? I wonder if the front suspension has a sway bar or sway provisions at all? Some of this question may be answered when we finally get our cars and can drive them ourselves and see for ourselves what is what.
 

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Yes, I am afraid that statement is correct. Look how long it has taken just to get the road show here! Test drives.....We'll be happy if performance enhancements become available in '09....unless aftermarketers get on the stick and make them first.....then there is that warrantee thing, huh......
 

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Some of this question may be answered when we finally get our cars and can drive them ourselves and see for ourselves what is what.
When I did a couple of quick turns durng the oh-so-slow test drive, the car has far too much lean and feels like it has an incredibly high center of gravity. With all the ground clearance it has, I would be tempted to do some substantial lowering and suspension stiffening to keep all four tires firmly seated during a turn. You'd think that MB could figure this one out for themselves.
 

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Great post on suspension. I was wondering if the EPS will be worth the extra money, if improving the tires(wider) and factory setup(lower) is the plan.
 
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