Now that we know HOW to improve Handling in a car,

[andylawcc]

to bump up horsepower and torque, you can go with force induction, better intake and exhaust, advance cams, adjusting timing and compression... and the list goes on.

but to improve handling, the only (financially sensible) things we can upgrade are
1) Tower bars/strut braces and anti-sway bars
2) shocks and springs
3) tires and wheels


is that it?

{modded and updated}

for the HOW part, read the first 20-25 replies,
for the WHY part, read everything after 30th.

 

[Kelvrick]

Weight distro. Weight in general.

 

[Vic]

2a) coilovers
4) bushings
5) custom alignment

edit: Kelvrick is right, weight and weight distribution. I also forgot brakes.

 

[Actaeon]

Center of gravity...

 

[boyRacer]

racing school

 

[Eli]

At heart, an engine is an air pump.

To increase it's performance, you must make it breathe better.

 

[Actaeon]

Originally posted by: Eli
At heart, an engine is an air pump.

To increase it's performance, you must make it breathe better.

Right.

But what does that do to answer his question?

EDIT:

andylawcc: You pretty much nailed down handling, sway bars, shocks, and most importantly, tires.

 

[andylawcc]

okay, i see.


pardon me, but what do coil overs and bushing do? aren't they part of the "shocks and springs" setup.

 

[Vic]

Coilovers would be part of the "shocks and springs" setup, which is why I used "2a"

Bushings would include those in the steering rack, better bushings could improve steering response and feel -- depends on the car.

 

[Zenmervolt]

Polar weight. For example, a mid-engine car and a front engine/rear transaxle car may both have 50/50 weight distribution but since the mid-engine car has virtually no weight at the "poles", it has much faster turn-in and is more prone to snap-oversteer since there's not as much polar inertia. This is a tradeoff, because it's more "comfortable" to have the weight at the poles, but you get more performance (though less "forgiveness") from having lower polar inertia.

ZV

 

[Eli]

Originally posted by: Actaeon

Originally posted by: Eli
At heart, an engine is an air pump.

To increase it's performance, you must make it breathe better.

Right.

But what does that do to answer his question?

EDIT:

andylawcc: You pretty much nailed down handling, sway bars, shocks, and most importantly, tires.

Didn't really notice his subtitle.. lol

 

[andylawcc]

heh, usually the question should be on the title line and not the subtitle's my fault.

 

[Ornery]

Tires are critical, and since they need to be replaced anyway, it's an economical "upgrade". BTW, what's the deal with the paper thin sidewalls? What do these boneheads know, that these guys don't?

 

Originally posted by: Ornery
Tires are critical, and since they need to be replaced anyway, it's an economical "upgrade". BTW, what's the deal with the paper thin sidewalls? What do these boneheads know, that these guys don't?

Because cars like that will never be driven at levels where a properly engineered tire/sidewall and suspension setup will drastically affect their handling.

 

[Vic]

Originally posted by: Ornery
Tires are critical, and since they need to be replaced anyway, it's an economical "upgrade". BTW, what's the deal with the paper thin sidewalls? What do these boneheads know, that these guys don't?

The tires on that F1 car cost more than the entire Civic and last less than 100 miles.

 

[GasX]

you can:
add or subtract air in the tires
put weight in the trunk of a RWD car

 

[Ornery]

I'm mostly wondering why the "engineered" tires don't have the tiny sidewall, "racing profile" that all the boy racers love. Why not emulate the "real" racing tires instead?

 

[Eli]

Originally posted by: Vic

Originally posted by: Ornery
Tires are critical, and since they need to be replaced anyway, it's an economical "upgrade". BTW, what's the deal with the paper thin sidewalls? What do these boneheads know, that these guys don't?

The tires on that F1 car cost more than the entire Civic and last less than 100 miles.

No sh!t?

I knew about the 100 mile part, but do they really costs 10s of thousands of dollars for a set?

:Q

 

[Zenmervolt]

Originally posted by: Ornery
I'm mostly wondering why the "engineered" tires don't have the tiny sidewall, "racing profile" that all the boy racers love. Why not emulate the "real" racing tires instead?

Because the rules and regulations set forth by the racing bodies mandate that the tires have tall sidewalls. If it were not for the rules, F-1 and CART cars would use low-profile tires as well.

Low-profile tires drastically reduce sidewall flex which increases responsiveness and gives the driver a more direct feel for what the car is doing.

ZV

 

Originally posted by: Zenmervolt

Originally posted by: Ornery
I'm mostly wondering why the "engineered" tires don't have the tiny sidewall, "racing profile" that all the boy racers love. Why not emulate the "real" racing tires instead?

Because the rules and regulations set forth by the racing bodies mandate that the tires have tall sidewalls. If it were not for the rules, F-1 and CART cars would use low-profile tires as well.

Low-profile tires drastically reduce sidewall flex which increases responsiveness and gives the driver a more direct feel for what the car is doing.

ZV

My searches on the topic find that not to be compleletly true.

 

[Zenmervolt]

Originally posted by: SampSon

Originally posted by: Zenmervolt

Originally posted by: Ornery
I'm mostly wondering why the "engineered" tires don't have the tiny sidewall, "racing profile" that all the boy racers love. Why not emulate the "real" racing tires instead?

Because the rules and regulations set forth by the racing bodies mandate that the tires have tall sidewalls. If it were not for the rules, F-1 and CART cars would use low-profile tires as well.

Low-profile tires drastically reduce sidewall flex which increases responsiveness and gives the driver a more direct feel for what the car is doing.

ZV

My searches on the topic find that not to be compleletly true.

Well, there are of course differences given sidewall construction, but all else being equal a lower profile means reduced sidewall flex and reduced sidewall flex means more responsive steering.

Now, there are tradeoffs of course, if the sidewall is too short it can cause problems with suspension compliance and other things so there's much more to consider, but it's a dead cert that the racers would use lower profile tires than they use now if they could get away with it under the rules.

ZV

 

[Howard]

Rip out the carpet, the unused seat(s), buy ultra-light aftermarket wheels (brakes if you are uber-rich, like the carbon fiber-reinforced silicon carbide rotors), install a real roll cage.

 

[Vic]

Originally posted by: Zenmervolt

Originally posted by: SampSon

Originally posted by: Zenmervolt

Originally posted by: Ornery
I'm mostly wondering why the "engineered" tires don't have the tiny sidewall, "racing profile" that all the boy racers love. Why not emulate the "real" racing tires instead?

Because the rules and regulations set forth by the racing bodies mandate that the tires have tall sidewalls. If it were not for the rules, F-1 and CART cars would use low-profile tires as well.

Low-profile tires drastically reduce sidewall flex which increases responsiveness and gives the driver a more direct feel for what the car is doing.

ZV

My searches on the topic find that not to be compleletly true.

Well, there are of course differences given sidewall construction, but all else being equal a lower profile means reduced sidewall flex and reduced sidewall flex means more responsive steering.

Now, there are tradeoffs of course, if the sidewall is too short it can cause problems with suspension compliance and other things so there's much more to consider, but it's a dead cert that the racers would use lower profile tires than they use now if they could get away with it under the rules.

ZV

Well, yes and no. The issue is to keep the unsprung weight to a minimum, and bigger wheels add more weight than bigger tires. So the idea is to find a balance between wheel diameter and sidewall profile to optimize for the least weight. But large sidewalls introduce flex which is bad for handling, but to eliminate sidewall flex in larger profile tires costs big money.
The average joe in his Civic just accepts the fact that his better handling wheel/tire combo is going to weigh a little more and to save money goes with the bigger wheels and lower profile tires.
The F1 guys go out and buy $10k tires (or get sponsored and get "free" tires, which is more common) that have kevlar sidewalls because (1) they can, and (2) they have to if they want to win. F1 cars also have carbon fiber suspension and million euro engines too.
It's all price/performance ratio and what's available on the consumer market. The average joe can't buy 60 profile tires that handle like they're on rails, so he buys 40's that are somewhat more affordable.

Another issue (though not for the Civic) is that F1 cars have onboard brakes (once again, to reduce unsprung weight and don't have to worry about brake clearance problems. In WRC, the rally cars run 19's and low-profile tires when racing on tarmac because they need 19" wheels to clear their monstrous brakes.

 

[mAdD INDIAN]

Originally posted by: Ornery
Tires are critical, and since they need to be replaced anyway, it's an economical "upgrade". BTW, what's the deal with the paper thin sidewalls? What do these boneheads know, that these guys don't?

Thin sidewalls reduce flex, which in certain scenarios increase handling because the tire can handle more stress.

If you look at F1 tires, they have LARGE sidewalls because those tires EXPAND and CONTRACT depending on temperature. And they expand by quite a bit; when they expand they become stiff, and they need those large sidewalls to handle the stress. Street tires don't handle 3gs of cornering forces or acceleration/de-acceleration forces. And F1 tires as a whole are worse than regular street tires. They only work in certain very small temperature ranges, take a while to get to proper temperature, only last an hour or so, and are ridiculousy expensive. However, in that narrow range of theirs, they have AWESOME grip.

Note, I don't mean regular tires are better than F1 tires in grip, I'm just comparing both in their entirety and not in their respective mediums. (yea I know, apples vs bread, but Ornery made the comparision and I'm just explaining it).

Anyway, in touring car series, those cars use thin sidewall tires similar to the one you pictured. In fact, SCCA World Challenge series require the use of Toyo tires that you can buy at your local tire store.

So yea, open up your mind Ornery and realize that different tires serve different purposes and work in different environments. You can't compare F1 tires to street tires, they work in totally different principles.

 

[Ornery]

"different tires serve different purposes"

Yeah, some are for real racing, and some are for poseur racing.

ARTICLE 12: WHEELS AND TYRES

• 12.1 Location:
  Wheels must be external to the bodywork in plan view, with the rear aerodynamic device removed.
  12.2 Number of wheels:
  The number of wheels is fixed at four.
  12.3 Wheel material:
  All wheels must be made from an homogeneous metallic material.
  12.4 Wheel dimensions:
  12.4.1 Complete wheel width must lie between 305 and 355mm when fitted to the front of the car and between 365 and 380mm when fitted to the rear.
  12.4.2 Complete wheel diameter must not exceed 660mm when fitted with dry-weather tyres or 670mm when fitted with wet-weather tyres.
  12.4.3 Complete wheel width and diameter will be measured horizontally at axle height when fitted with new tyres inflated to 1.4 bar.
  12.4.4 Wheel bead diameter must lie between 328 and 332mm.

There is NO mention that the sidewalls have to be wide. The wheel size is fixed, but not the tyre profile.

I don't know who this guy is, but his explanation sounds as plausible as anyone's, and I agree:

"I also think that if we went to low profile tires, they'd be less of a factor as far as any advantage over one another. "

They are on low profile - for the width of a tyre expected to do a job.
The street-craze to make very low profile tyres are OK for posing in car parks.
They are useless at handling cornering.
When the wheel camber changes during cornering an extremely low profile tyre cannot keep as much footprint on the road.
Watch the F1 slo-mos through corners and you can see them suffer the same problem.