Sunday, March 25, 2012

Congratulations Mercedes... welcome back to the car business.

I've written several articles in which is easy to understand that I hate most Mercedes.
In particular I hate the A and B class Mercedes. But I was right to hate the A-Class, and WAS is the keyword.
The new A-Class is a car built with logic and brains. So I congrat Mercedes for quitting the construction business and entering the car making world.
The new A-Class is no longer built in high but rather (and like this post I've written before) like the best cars on it's segment. It looks like a mix between the audiA3, the Golf and the BMW3 series.

My Opinion:
I'm honestly anxious to test-drive this car. In engineering terms this makes perfect sense and it's a REALLY big evolution from it's ancestor. But dynamically you must drive-it to feel-it. But I will try to pull a few strings (a.k.a. contacts inside Mercedes) and make a real test drive and review out of the next article.

Improvement is obvious and easy to spot. The Old A-Class Mercedes was both ugly and dangerous. It was a dynamically nonsense and the tip-over during the moose test proved-it immediately.
But this one, this one is a CAR... not building.
Does this mean the car loses habitability? Probably, but who cares? IT'S A CAR! Not your living room! It's supposed to carry you from your work-place to your living room at home in a safe and logical manner. And when you arrive home, then you can enjoy the comfort of your living room.

Like the article mentioned above, this car clearly copies a lot from it's rivals... but if sometimes I condemn this, in this particular case I applause-it and congratulate Mercedes for the excellent evolution.
Copy-cat? Copy-cat is good when it comes to improving the "should never be born" old A-Class.

 More like Brothers!?

I've seen that ass before!!! Sisters for sure!

So I've clear that Mercedes pulled out the biggest automotive Orgy in the history of the auto-mobile. It must have been quite a Gang-bang between the Audi-A3, the Citroen DS3, the BMW 1 series and the Volvo S60.... but hey, it worked and I like it.

It's my new favourite "bastard". And I'm actually thinking, that if this car drives? I could even consider-it in my buy list...and that is quite a compliment.

Dislikes? Sure, a couple so far... but nothing odd

I would agree to these "X" shaped venting decorations, but the Mercedes logo is more logical and I can only understand this if it's going to première the car in the next X-Men movie.

I can't understand this latest trend of substituting a steel sheet (and a B pillar union reinforcement bar) with heavy-glass. Want to see the sky? Buy a Cabriolet... but don't go fitting something heavy on the top of the car, or it will unsettle the handling. It's just stupid!

It's going to be Front Wheel Drive... and I kinda Expected it to be Rear Wheel drive, but copying out BMW didn't go that far. Pity, cause the car is prettier than the frankensteinic BMW 1 Series, but I doubt it will be able to eclipse it's chassis driving everything through the 2 front wheels. Guess it's a wait and see.

It seems that AMG is already working on it, and there are plans for an 1.6 and 2.0 direct injection turbo, making the car available from factory with up to 200bhp...but the cherry on the top is that it will be available with an optional 7 speed gearbox, and that could make-it quite a rocket. That one I MUST TRY! ;)

While some of the best car makers I've always loved are making mistake after mistake, some of the ones that I've always hated are making progress after progress and creating interesting products. I like this! I would love a world with nothing but well engineered, involving, passionate cars.
Seems like I'm going to have to test drive a Mercedes because I want to, instead of HAVING to,and at the same time have to test drive a Honda because I have to instead of actually wanting to... you have no idea just how bizarre this is.

Behold, the best Mercedes since the Gullwing (in my scale):


Saturday, March 24, 2012

LFB... the brakes are not made to make you go slower

well, not ONLY to make you go slower.

Quoting Mario Andretti, "It is amazing how many drivers, even at the Formula One Level, think that the brakes are for slowing the car down."

Of course the brakes will stop your car by dissipating kinetic energy (from the car's movement) into heat. But that's only half the story.

Welcome to LeftFootBraking.
A trained driver will be able to use it's left foot to brake. It's a hard technique and requires practice to master, mainly because you need to know when to do-it and train your foot to the right pressure.
It is however an excellent technique to make you go faster. That's right, braking will make you faster.

If you think about it, why would you need your left foot to brake? Why cant the right foot do -it? the answer is simple: because it's busy accelerating.

So LFB is used along with acceleration. WHY?
OK, When you normally brake, the car's weight shift towards the front and this will make the front wheels "heavier". That's why people at driving school teach you to enter corners under braking, allowing the front axle more weight and better grip.
When you accelerate, the opposite happens. The weight sifts to the rear of the car and the front end looses grip, widening your trajectory.

Some cars have a natural understeer tendency. And this doesn't need to be suspension setup. Just try a turbo FrontWheelDrive car and step-on in mid corner to feel it immediately understeer as the front tires give up on both steering ans gripping while also being pulled up by weight shifting.

What if you could have both? If you accelerate, but then brake just enough to maintain weight transfer under control (or even shift forward), allowing more pressure under the front axle and increasing grip. That's LFB.

In a powerful FWD car it's very important as the brakes will also "dame" the engine power and maintain control without decelerating (maintaining intake gas and engine movement inertia).

But this is not only true for FWD cars. Any car can benefit from this as it's directional wheels are at the front and braking shifts weight to the front.

For instance, my s2000. It's a rev2 chassis, so it has buil-in Understeer-under-acceleration to make the rear-end let-go more poised and predictable.
But I'm used to it and sometimes I'm counting on it to help-me steer the corner out under power with minimal steering and maximum grip.

By The Way: don't try this in a car equipped with the standard ESP. It will not understand acceleration with braking and shut-down your engine to emergency mode. IT'S DANGEROUS!!!! That's one of the reasons I hated the Audi A3.

Need proof?
I'm using this technique since 1997 and I normally do-so in some perfectly drawn bends I have on my Work-Home trip. I abuse the car so much on those right turn corners, that my tires are always rounded on the outside from the left side of the car and rounded on the inside on the right side of the car, as you can see here:

My rear right tire:

My Rear left tire:

(the inside is worn because of aggressive camber, but not as worn as the right tire was...also take a good look on the outside of the's rounded and worn-out)

My front left tire:

SOOOOO this should establish that those right corners are made frequently under heavy cornering (these were reinforced side-wall Falken FK452..not budget tires)
If I LFB under those corners (as I do), the left brakes pads would normally suffer a heavier load....
And here it goes:

It's clear that the brake pads on the left (front the front left wheel) suffer a lot more stress than the right wheel ones.

Toyo R888 + 5zigen Gn+ Proracer + S2000 = FUN

I've been waiting for some time now to write this article.

I've been driving the S2000 for quite some time now (err make that - it's my daily driver since 2007).
As a car lover and 100% petrohead I am, I usually wakeup 2 hours earlier than to avoid traffic and only return home after the gym training session, avoiding traffic once again.
This is not JUST to avoid the stress, but mainly to have the road clear enough for some daily fun.

Now I've always defended that the S2000 OEM suspension was good and that I really didn't get why most owners switch to tuner suspension.

Well, this time, when I needed to change my tires I decided to go crazy and fit my racing 5zigen GN+ with some Racing Toyo R888 rubber.
I've had a set of these before but never tried them on a every-day basis.

So after a month on these beauties what can I say?

I love the lack of NVH technology... the tires roar constantly while contacting with the ground and it's just so hardcore that it's good.

The car used to get sideways with ease, well...not any more. You have to really push things to get a tail out, and when you do, the slightest correction is immediately carried out. No delay, no fuss... just ask what you what and keep accelerating enough to allow the brilliance of the chassis and the super perfect tires to make your wishes out in perfectly executed commands.

The grip level is so high that it became evident in the first 10 minutes I drove it on the road WHY there are after market suspension kits to the Rev 2 S2000 for street use.
Using the stock suspension on the Rev2 chassis, this setup will enhance the settings and make them excessive.
The rev2 S2000 is more controlled and poised on the limit. This is because of some understeer-under-acceleration setup, making the let-go more progressive since the front end bites-in less aggressively.
If you add huge gripping tires to this setup and leave-it as it is, the car will get a bit on the "all-or-nothing" side. Step-on the gas in a bend and the rear grip will up the car's nose and you'll feel understeer...Step-off and the front-end dives-in and grips like hell creating oversteer.
It's easy to get used not to step in or off to much and the car will grip brilliantly, but this suspension travel will immediately get you on the phone with your car parts supplier.

A lot of people ask-me about these tires behaviour in the rain.
About the rain: If by rain you mean pouring rain, then I have to say that this is not the rain tire. It's got some groves to channel out water, but it's only to make it minimally's far from safe to normal driving speeds.

However if by rain you mean wet tarmac, then get your facts right. The compound if so soft that it will grip even cold. This car can turn so fast in the wet tarmac running R888's as it would turn on the dry tarmac using normal tires.

I've already reviewed these tires before here, so I'll just add that my new favourite sport is outside overtaking on hard corners. It's wonderful to overtake others on the outside while they desperately try to brake their cars into the corners with their tires screaming all over the place.
The only bad thing is when you overtake-them they immediately brake and leave you some distance because the tires pick-up just about every little bit of dirt you have on the road and projects-it out the back of the car into the front end on the one chasing you.

Brilliant tires... and kind-of addictive ;)... they definitely can make you a "show-off'r"

The CRZ that kills birds...

...but makes the guy paying for it feel alive and happy.
It's no news, the CR-Z ir FAR from being the acclaimed CRX replacement.
I tend to think that If they called it Honda Green, or Honda TweetyBird...or even Honda CRU, I wouldn't hate it as much.
But Honda called the CRZ the "Next Step from the CRX", hence the "Z". That was just offensive. It seems like the company that created the CRX forgot their own product, or the new guys working there never ever understood the "old"guys project at all.
The CRX was about Lightness and Nimbleness coupled with a state of the art engine that pulled out 100bhp/tonne in it's best evolution.
Years latter, Honda managed to:
   - kill lightness with a huge battery pack!?!?
   - kill nimbleness with a high-stance car instead of a LOW-to-the-GROUND sports one.
   - killed the engine power using a IMA unit that pumps out less than 80Bhp/litter and a joking 114bhp top + 14bhp with electric assistance.

So, is Honda selling worse a product marketed as a better one?
NO, and YES.
No, the CRZ is not worse than the CRX if you are a bird and feel that the CO emissions is disturbing your libido function.
No, the CRZ is not worse than the CRX if you have an accident and absolutely need to walk out of it with nothing but an headache.
No, the CRZ is not worse than the CRX if you think that a sports car should have the same economy as a diesel vw lupo.
No, the CRZ is not worse than the CRZ if you like that odd rear-end
Yes the CRZ is far worse than the CRX if you like cars
Yes the CRZ is far worse than the CRX if you think a sports car needs an engine
Yes the CRZ is far worse than the CRX if you like a nimble and light chassis
Yes the CRZ is far worse than the CRX if you like to lightly tune up your car to your personal preference.
Yes the CRZ rear end is ugly and difficult to live-with compared to the CRX.

To make a long story short (quoting my self talking to a friend that brought the CRZ), Honda makes you pay for the car, but built it having the bird and pigeons in mind, NOT YOU!
He replied: But I've already brought the thing...
 ...Is there a solution for this mess?
No need to panic.
When Honda released the Eighth generation Civic, the European version on the coupé was a disgrace. The car has lost it's independent rear suspension that made the EP3 (7th gen) chassis so good.
However, the 8th gen sedan had the same EP3 independent rear suspension...but was an IMA hybrid!
Weird! Honda puts the brilliant K20A engine in the Coupe type-r with a bad suspension...and the poor stupid IMA hybrid in the sedan, but with the best rear suspension the civic has ever had.
So how would one save this car? Well Honda may be selling crappy products, but they tend to do so on the European market only, cause the Japanese Domestic Market version of the 8th gen Type-r has the brilliant K20 Engine (pumping over 220bhp from it's Natural Aspirated 2 litre engine) coupled with the sedan chassis that suffers an extreme diet.

The very same approach could be used on the CRZ.
Dump the batteries, dump the IMA engine (maybe it will be useful to build an epi-lady or something like that) and fit the K20A with the 6speed Gearbox into it, then lower and stiffen the car.

Now I've been saying this since I've seen the first car specs with a claimed 200bhp from an extreme IMA unit... but Honda failed to deliver.

Meet the K24 CRZ from Eibach

It's pointless to tune a chassis without removing unnecessary weight. And a Car with 200kg of batteries that return less that 20bhp...needs a diet.
Together with the batteries, an engine that produces no power at all is also no good, so out with the IMA and in with...

... the K24. It's the same K20 from the Type-R Civic and JDM Fourth Generation Integra but since it's being used in the Accord, an extra 400cc has been added to cope with the extra weight.

The result? Well the result is FINALLY a CRZ. A decent successor for the CRX.
This car is created for the ones Paying for it... it's a driver's car, not the TweetyBird's car, and since the driver is the one paying for it, it feels just right.

The K24 is producing around 280bhp and that's more than double the original 1.5 unit's 112bhp...that's 116Bhp/litre and its close enough to the european version S2000 120Bhp/litre to be called an evolution worthy of this day and age.

If you like you can watch the video of the test drive from Banzai magazine HERE.

Honda's new CEO means business...or at least it should

Being CEO myself, I tend to look at other CEO's with a sceptic viewpoint.
They are normally "dime counters" (a.k.a. economists), "professional bullshitters" (a.k.a. economical engineers...which along with "dime counters" and "politicians" created the economical crisis we live today) or plain managers. These last can be divided into 2 types (project managers or traditional mangers)...and then the business type will dictate it's type-for-the-job index.

I'm, in truth, a Project Manager with engineering roots, witch makes me suitable for companies who's business relies essentially on Projects... traditional manager are suitable for "operation" or "process" based businesses.
The automotive business is a mix of these 2. You need to constantly create NEW cars, described as Projects (creating growth by improvement), and then you need to mass produce these cars as what's described as an operation (archiving consolidation).
Till recently, most CEO's are background "dime counters", making them the worse person in the job for creating interesting products, but the best to make them cheap.

Honda is an Engineering Company.
Like most successful engineering companies, It's been run by lovers.. No, I don't mean the pretty blond that dates the CEO making everyone believe that she's just his secretary, but rather the CEO it's self in love with the company. Mostly this means that in an engineering company, they are Engineers.
As with many Engineers in a Management Position, they will soon need to acquire Management Knowledge and that can create 2 different types of CEO's... The Project Manager type, and the Process Manager Type.
That doesn't mean however that they can manage as well as they would love to.
From It's creation till today, Honda had 7 CEO's:
  • 1948–1973 – Soichiro Honda
  • 1973–1983 – Kiyoshi Kawashima
  • 1983–1990 – Tadashi Kume
  • 1990–1998 – Nobuhiko Kawamoto
  • 1998–2004 – Hiroyuki Yoshino
  • 2004–2009 – Takeo Fukui
  • since 2009 – Takanobu Ito
I've been an Honda fan until the recent "eco mania disease" I call Honda's DarkAge. And that's Takeo Fukui's ruling time. Takeo Fukui's has a degree in Chemical Engineering (ok, not quite the mechanical guy I expected), but it's curriculum includes Honda Racing and Honda R&D, so I would expect better from him.
Honda used to create good consumer projects with economy and affordability in mind, and then go weird and create type-r versions of those same products for the passionate ones. That seemed like a perfect thing until politicians (probably the only thing worse than economical engineers), decided to use the car's CO emissions as a pretext for excessive taxation. And that doomed the industry.
Honda, much like Toyota immediately gave into this mass stupidity where instead of using the taxes already being paid (for ages I might add) to plant trees and filter out carbon, the cars have to emit less and less carbon. I'm surprised that the damn politicians didn't yet fit a face mask with a catalytic converter to each and every Olympic athlete and football player...I mean when they breathe deeply under physical stress, they will be emitting more carbon than a prius!!!

To sum up, the industry was already counting dimes instead of focusing in creating good products, when the politicians joined the game and made these  shift their entire product range to dull, and ultimately bad products. Why the BAD word? Cause a hybrid vehicle will eat more gas than a full engined gas car (because it lacks engine and has excessive weight due in part to the huge battery pack in the boot)... and the battery pack is created from heavy metals mined and fused creating more impact on the environment then all the f1 engines in the world together...and this is just part of the equation,, cause when the life-cycle ends they have to be recycled and this creates more impact...or left to rotten that is even worse.

So it's true that a hybrid is a bad car right? Not quite.
In the essence of the tree-huggers GREEN car, the hybrid is  stupid and bad idea. But if you reduce the battery pack and replace the metal battery for the brand new membrane accumulators (rendering it useless for consumption reduction purposes as it's still an emerging technology and doesn't yet supply/accumulate lot's of energy), and then use the electric motors to torque the huge gas engine further than it would (like Lexus did, like Porshe concepts to do) than it's actually a good thing.

And then we get to the article:
Meet Honda's CEO - Takanobu Ito.
He entered Honda as a Chassis Design Research and Development Expert, and was one of the responsibles for the NSX all aluminium chassis. He was one of the Engineers behind one of Honda's best project till date.
So I'm expecting him to be THAT kind of good CEO that creates good products instead of destroying them to "count dimes".
And he decided that the Civic should have a Type-r again, and a new NSX should arise... and it's a hybrid one.
Now before grabbing your tomatoes, remember my previous paragraph...the hybrid that actually doesn't give a damn about the birds and the squirls and their erection problems due to CO' the only Hybrid that actually makes sense.

The Rising Sun prepares for a come back
Takanobu Ito is preparing the Type-R come back (although unsure about the type-r badge yet... can't quite understand why).

And the new NSX concept is beautiful as you can see...
...but hey, Honda's new design is not the issue, but rather the lack of engine, so the new NSX is pretty much like the old one and uses a V6 (not my favourite platform, but after seeing Honda sell the CRX replacement as a 1.5hybrid with 124bhp...I'll take anything that outputs over 100bhp/tonne)

So where does the Hybrid part fit? Well picture a rear wheel drive car that's a 4wd car. In truth, the NSX is a MECHANICAL ENGINE-TO-GEARBOX-TO-WHEEL RWD platform, but a couple of torque electrical engines have been built into the 2 front wheel hubs, and that means that it can torque the front wheels into a corner with electronic precision that is very, VERY efficient and hard to beat.
Check my article comparing the Asterio Roadster with the Audi eTron that uses the very same principle.
NOW THAT's an Hybrid I would buy. Pure, atmospheric mechanical grunt driving the rear wheels and 2 torque engines driving the front and signing you into PERFECT apex lines, melting rubber on the way due to the extreme G's it's pulling.

It's a much needed change
Honda has finally realized that the ONLY cars they built that are successful, are the "old" ones.
The Accord, and the CR-V are today's success story's...followed by the not so successful (no wonder) Odyssey, and then comes the flops, the CR-Z, the Inside and the Ridgeline...leaving the obvious huge failure (with vomit provoking design) Crosstour.
The Market Is reacting to this lack of vision and things seem to start to change. My S2000 is pulling the 8 year line and I'm thinking that one of these days it will have to stop being abused dally and start having a more calm weekend abuse only...but how would I buy a daily driver that doesn't render-me a depressive state? not much to choose from unless I want another 8 year old car :S!
FINALLY Honda is planing to move out of the closet it's locked it self in... and together with Toyota's rethinking the Supra and creating the 86 replacement, I would guess that the sun will rise again.

Wednesday, March 7, 2012

The's all about the grip - Understanding tires Part 4

This is the 4th of 5 posts about tires.
1 is about how important it is to understand tires and what to consider when buying them.
2 is about the tire measures and proportions one can see in the tire walls.
3 is about tread design
4 (this) is about compound and structure
5 is about maintenance and repair

Tires are supposed to create drag. That's it's main purpose because by doing so they will allow you to grip the road. That's one of the things I've never really understood when people buy budget tires (plastic model copy or a well known tread design) or when they buy energy "efficient" tires that reduce rolling resistance. These are 2 examples of what's not to do. The plastic compound doesn't grip and the budget tire with low rolling resistance lacks structure and will bend all over during cornering, loosing shape and ultimately not griping.
For some reason people love to see their cars are equipped with competition sourced technology, but then go the opposite way when it comes to tires.

This is a post about the tire compound and the tire's structure.

Starting with the compound.
As the name states, a compound is a new material composed by several different raw materials in order to archive together what none of them would be able to alone.
Evidently, talking about tires, one always talk about a rubber compound. However the ingredients and cure involving these compounds are mainly composed by rubber, several others are added in different parts of the process and quantities, allowing for a product more suited to the usage its going to be subject to.
Most tire rubber compound mixes include:
  • Rubber or polyisoprene (sometimes cut with Styrene-butadiene co-polymer for low budget tires)
  • Polybutadiene (to control temperature build-up)
  • Halobutyl, Chlorobutyl or Bromobutyl  rubber (user for air insulating the inner side of the tire, being Chlorobutyl the most expensive option... see those tires that loose pressure too often? either they were cheap or they have a puncture)
  • Halogen (used in chemicals bonding process)
  • Carbon (increases hardness, resistance and longevity)
  • Silica (used in High performance tires together with carbon to increase durability by lowering heat build up)
  • Sulphur (not for the evil smell but rather to allow rubber molecules to link with each other during the eat and pressure of the vulcanization process...and thank Charles Goodyear for that process)
  • Zinc Oxide to catalyze vulcanization process, together with antioxidants and antiozonants that protect the rubber against oxygen and ozone that tend to make cracks all over the rubber during the vulcanization process.
Together with the rubber compound, a tire is also made out of steel and fabric, but we'll be covering that later.

There is no one single mix recipe. Different manufacturers would use their own ingredients choice and percentages according to brand and product line...but a simple example would be something like:
  • 60 to 65% Rubber (SB rubber would be natural rubber cut with Styrene-butadiene making it cheaper and ultimately worse)
  • 28 to 35% of Filler compound made form Carbon and Silica
  • 1.5% Catalytic ingredient like Zinc Oxide
  • around 1% Acid
  • around 1% Chemical Accelerators
  • 2 to 3% Oil 
  • around 1.5 to 3% "special ingredients" (silica mostly but depends on the tire brand and tire product line and the amount of silica already present on the filler compound)
So now we have a recipe of ingredients and proportions... and like the cakes one can cook at home, the ingredients have and order and time to get mixed in the blender. It's the same with composite materials, so rubber compounds are no different. Much like the cake, this recipe will have it's ingredients mixed together in a huge blender machine under some counter rotating mix-blades. The big difference here is that unlike sugar, flower and eggs , these ingredients are denser and heavier. As a consequence, the mix eats up lots of energy, generating loads of heat. If this was your cake, it would start cooking while under mixing and that's not desirable, so the tires mixing process is cooled to control temperature and avoid pre-vulcanisation (the cooking part)...don't get me wrong, temperature is good and will allow better mixing, it is however difficult to keep uniformly controlled. Better compounds require an expensive and energy consuming process that will process smaller amounts at a time in order to ease the process and produce better compounds...but in smaller quantities with an expensive process, making this part of the reason why better tires are more expensive.
Back to the cake, after mixing, you normally tender the mix into a mould powdered with flower...and then again, the tires are also tendered and extruded several times into a mould powdered in talc.

And again, just like those cakes your grandmother used to do that would take forever to mix and cook are far better than the ones you buy in the supermarket, rubber compound mixed without rush and using the best of the best available tools with perfect temperature control and movement control to assure the best mix will produce the better, more uniform compound. Like most things that are built, taking time to do it right will produce better results.

I'll be continuing the rubber compound process story later on in the "structure" section.

Now just how much of a difference can tire compounds or "recipe ingredients" do when one plays with the proportions?
First comes the original rubber compound. We can start a rubber compound with 4 different rubber materials:

  • Natural Rubber - This is an expensive raw material and is also very soft so it's essentially used as a part mix to BR (Polybutadiene Rubber) very common in heavy load tires (truck tires).
  • SBR (Styrene-Butadiene Rubber) - This is the most common used rubber base used for tires. The Styrene/Butadiene mix varies a lot. For instance, the most common mix is 20% to 25% Styren on 80% to 75% Butadiene. If you want an excellent gripping tire that will work in cold and wet conditions, all you have to do is UP the Styrene on the mix to say something like 40%. But the recipe is not just to UP the Styrene on the mix as a tire needs to maintain structure and be able to endure more than 4 some hardness is essential. This behaviour is a result of the compound mechanics that make it generate more heat while being deformed. 
  • BR (Polybutadiene Rubber) - This is the primary bi-product of an oil refinery. It's a much "plastic like" rubber that is very hard and generated a lot less heat while being deformed. Now one might think that this is the rubber used in those budget tires that wear little and grip even less...and be partially wring about it. Ever seen a F1 race be interrupted by a pace car and make all the F1 cars start swinging behind it? They do so to stress the tire compound enough to generate heat and maintain tire grip levels...and they do so on hard compound tires that are very good enduring abuse, but the high Polybutadien compound they use can't get too cold or it will not grip.
  • Butyl Rubber and Halogenated Butyl Rubber - This is a soft rubber that bounds in an very tight and elastic way. Essentially it's very soft and a very good sealing rubber. It's used inside every tire to ensure a tight air seal. 

 Then comes the filler compounds, and these are essentially 2:

  • Carbon black - As it's expectable, carbon adds hardness and friction resistance.
  • Silica - Silica is a recent material in tire manufacturing (being used since the 90's). It enables the tires to endure more while decreasing roiling resistance and increase grip.

These days Carbon black + silica are widely used to produce tires that are able to generate grip without drawing so much energy while maintaining it's endurance and friction resistance characteristics.

The Mixing of all these materials, as already explained is mechanically and temperature controlled. The initial mixing is done around 150 degrees Celsius, mixing rubber and filler together. The rest of the ingredients is mixed in later and cured at a lower (100 degrees) temperature.

The structure
These following tire cut drawing (Property of toyo tires 
The tire structure starts with the tire bead components. These are marked in pink and are a steel cord wrapped in rubber. The tire bead will ensure a perfect fit between the tire and the rim. Its steel cored for the simple reason that while extremely endurable and stuff, steel also has elasticity. 
While inserting the tire in the rim, the machine will stretch the tire bed trough the rim lip (witch is a good 1,5cm higher that original rim and tire bed diameter). The steel bed will allow for this to happen with elastic deformation and return immediately to it's original size after passing the rim lip. This is one of the reasons one should not fit a 17inch tire in a 17,5 inch wheel. The bead is built to specification and takes the elastic deformation onto account...over that and you create uneven plastic deformation and that will not return to it's original form.
The grey part on the cut drawing in the inner liner. It's purpose is to insulate gas inside the tire under pressure. It's built from soft Butil Rubber pressed against another layer of steel wire mesh reinforced rubber.
The blue part is something not all tires have. It's a reinforced side-wall. This makes the tire very hard and resistant, but also less deformable and also less comfortable. It's a very important part of a performance tire because the stiffer it is, the less flex and bending of the tire structure (and tread area in consequence) under heavy cornering.
With the inner liner formed, the tire will gradually be layered.
The tire wall you see in blue will be the LAST part of the tire assembly process.
This type of construction is called radial construction as the tire is laid out in layers that will each have its own radius on top of the earlier one.

This other cut drawing shows a bit more on the tread bed and radial layers.
With the tire bed already laid out, the body ply (red layer) is layered on top of it.
This layer will add thickness and hardness in the tire structure.
The next 2 layers (green and orange) are made from smaller steel wires pressure-sandwiched in rubber and criss-crossed (each layer has a crossed orientation from the one below).
The Yellow layer is a nylon fabric tissue layer.
Last but not least comes the real tire tread compound layer. This can be made as one single layer or a mix of 2 different layers (a harder and a softer compound):

  • The best tires are made from the same kind of soft rubber compound into one single tread layer.
  • Good tires can be made from an inner softer compound and an outer harder compound. This will make the tire grip well in the wet while new (because the groves are deep and the soft inner compound allow more flexing of the tire tread pattern), and when they start wearing the loss of grip due to texture will be replaced by better rubber compound that will not allow so much water through but will generate more friction, compensating on the actual contact grip side.
  • Finally the "honey-moon" tire as I normally call it. Its an Inner hard compound tire wrapped in soft compound. You will have lot's of grip that will go away with the soft compound leaving a harder more durable compound that will grip less but will "live forever".
There are some exceptions to this rule and understanding how a tire compound can be mixed together, one can realize that there are several types of soft and several types of hard compound. A Budget hard compound will be hard because of excessive carbon-black... this will endure and not grip even when hot. A competition Hard compound will be made from high Polybutadiene Rubber compound, making it grip with high temperatures and endure abuse. Following this line of thought:
  • You can have a soft(outside)-hard(core) compound tire made to grip a lot without needing to warm-up and then wear to the hard compound made to grip while hot. This would make an excellent wet-to-dry competition semi-slick tire. The outside softer compound with groves would run colder because of water and channel water out of the tire's way ensuring grip; as the track would warm the softer compound would wear faster generating more heat and gradually let in the harder compound already up to heat spec.
As in our cake, after mixing, tendering and pressing against a mould, is time to cook.
Now cooking a tire requires a lot more than heat.
After all the layers are put together (already under heavy mechanical pressure) the rubber in the tire is still ductile. Like most composite materials, an high energy reaction is needed to bound everything together at the molecular level.
Remember the Halogen, Sulphur and Zinc Oxide? They all come to life here when the tire is pressured cook inside a huge doughnut shaped oven. This is called the curing process (as in most composite materials).
The tire is placed into the lower mould bead seat, a rubber bladder is inserted into the tire. While the mould its self is closed, the bladder inflates, creating pressure. A recirculating steam gas or water will then add heat to the process.
The tire will cook under around 350PSI at 180 degree Celsius for anything from 20minutes to over 20 hours, depending on the compounds, size and thickness of the tire.
Some tires require a cool down process using a cold inflater to allow the tire to maintain form.