During the last Century, both evolved considerably – till the ‘Euro-II’ like Pollution Norms got the better of them. For, the Carbs worked on a fundamental principle of ‘reaction’, which could easily get stifled for many reasons. Whereas man, wanted to be literally in the Driver’s Seat – as always.

And thus, as the cliché of necessity being the mother of invention goes, a System of ‘controlled-feeding’ of Fuel + Air + Ignition Spark to the ICE Cylinders in the early ‘80s evolved. A ‘system’ like that had to be based on the engine’s ‘needs of the moment’, such as the load on it, its rpm, vehicle’s road speed etc.

Such a ‘system’ had to ensure that the ‘ob-Nox-ious’ Pollutants were kept to a bare minimum all over it’s operating range – not to mention squeezing the maximum ‘mileage’ out of the last drop of fuel that went into it. Thus ‘fuel-injection’ systems were born – replacing nearly a century old Carburettors.

For the uninitiated, ‘MPFi’ stands for ‘Multi point fuel injection’. Such a system ‘injects’ fuel into individual cylinders, based on commands from the ‘on board engine management system’ Computer – popularly known as the Engine Control Unit or the ECU.

MPFi Systems can either be: a) ‘Sequential’ i.e. direct injection into individual cylinders against their suction strokes, or b) ‘Simultaneous’ i.e. together or all the four or whatever the number of cylinders, or c) ‘Group’ i.e. into Cylinder-Pairs.

These techniques result not only in better ‘power balance’ amongst the cylinders but also in higher output from each one of them, along with faster throttle response.

Of these variants of MPFi, ‘Sequential’ is the best from the above considerations of power balance/output.

‘SEFi’’, as advertised by Ford, stands for ‘Sequential Electronic Fuel Injection’, which technically is the best of the above variants of ‘MPFi’. Hyundai/Maruti ‘MPFi’ systems are in fact ‘SEFi’ too. The erstwhile Cielo’s and Matiz’s had the (b) or (c) variants of above MPFi systems.

On the other hand, older Opel-Astra’s had a ’single point’ fuel injection system, which is in between an Mpfi and the now obsolete Single-Carburettor systems.

The ‘Fuel Injectors’ are precision built ‘Solenoid Valves’, something like Washing Machine Water inlet Valves. These have either single or multiple ‘Orifices’ which ‘spray’ fuel into the Fuel inlet manifold of a Cylinder upon actuation, from a common Rail/Header pressurised to around 3 bar, fed by a high pressure electrically driven fuel pump inside the Petrol tank of the Car.

The ‘on-board’ ECU primarily controls the Ignition Timing and quantity of fuel to be injected. The latter is achieved by means of controlling the ‘duration’ for which the Injector solenoid valve coil is kept energized – popularly known as the ‘pulse-width’.

In general, an ECU in turn is controlled by the ‘data input’ from a set of ‘SENSORS’ located all over the Engine and its Auxiliaries. These detect the various ‘operating states’ of the Engine and the performance desired out of it. Such Sensors constantly monitor: 1. Ambient Air Temperature, 2. Engine/Coolant Temp., 3. Exhaust/manifold temp., 4. Exhaust ‘O2’ content, 5. Inlet manifold vacuum, 6. Throttle position, 7. Engine rpm, 8. Vehicle road speed, 9. Crankshaft position, 10. Camshaft position, etc.

Based on a ‘programmed’ interpretation of all this input data, the ECU gives the various ‘commands’ to the Engine’s fuel intake and spark ignition timing systems, to deliver an overall satisfactory performance of the Engine from start to shut down, including ‘emission control’.

This/Part-1 of a 4-part Article is an attempt to familiarise the average ‘BS-II/III’ Car Owner as to what actually lies beneath their Bonnets. In Part-2, we’ll talk about the do’s and don’ts relating to MPFi Cars. In Part-3, for the more curious ones, we’ll see how the stuff works and in Part-4, we’ll explore the commonly encountered problems and DIY-Trouble Shooting.

Immediately, to get the best out of an MPFi System, one should always use – a) The OE recommended Petrol Additives with the ‘Regular’ Unleaded or the new generation ‘Premium’ Petrol’s and b) NEVER Tamper with the OE Wiring Harness of the Car – EVEN to install the ubiquitous Music System OR any other Electrical Accessory - other than those ‘approved’ by the OEM/Dealer and ‘installed’ by him, as these are designed to suit the Car’s OE Central Wiring Harness ‘Couplers’ provided for the purpose. ‘BUTCHERING’ OF THE OE-CWH IS AN ABSOLUTE TABOO FOR MPFi CARS.

So yours truly again e-picked the brains of his TyreGuru – Mr. Sudershan Gusain – and this is how he enlightened me…

Tyre burst or explosion, two different things tho’, is an interesting topic and internationally, very few studies have been made in this direction. Here are some general explanations about them and they apply equally to automotive as well as ACTs:

A tyre burst/explosion is not so common a phenomenon but:
• It is difficult to detect before it happens.
• It may have multiple causes.
• It can have tragic consequences.

Some figures from Canada indicate that tyre explosions account for 1% of all accidents leading to deaths over there.

Before we proceed further, we should distinguish a BURST from an EXPLOSION:

BURST
A Tyre Burst can be defined as due to ‘mechanical deterioration’ of tyre material, thus weakening its ‘structure’, resulting in a sudden and violent release of the air.

The causes of a tyre burst can be classified into 2 categories:

MECHANICAL CAUSES
• Excessive tyre inflation.
• Improper bead seating on the Rim.
• Structural fatigue of the casing.

CHEMICAL CAUSES
HEAT is the main cause that can lead to a burst of chemical origin. Various chemical reactions can happen when heat inside the tyre builds up. Thermal decomposition of rubber then occurs and it chemically breaks the tyre material into its original components viz oil, gas and char.

EXPLOSION
Explosion is a sudden expansion of a gas under pressure. Flammable gases with relatively low self-ignition temperatures can get formed inside a tyre due to heat and/or decomposition of tyre material due to many other causes. And when the internal temperature of a tyre becomes higher than the self-ignition temperature of such gases, an ‘explosion’ can occur. However, for it to happen, the following conditions are to be met:
• Concentration of enough inflammable gas.
• Inside tyre temperature higher than the self-ignition temperature of the gases formed within.
• Oxygen concentration inside the tyre higher than 5.5%.

A chemical explosion of such a nature is much more violent than a burst, as it occurs at much higher pressures - usually ~ 500psi or more.

For a tyre explosion to occur, a high degree of heat is required. The causes of such high heat generation are due to following possibilities:

The most common cause is ‘wheel welding’. Rubber will start to decompose around 250°C. With the increase in internal temperature, the mix of oxygen and flammable gas auto-ignites at around 450°C and an Explosion can occur.

Use of a welding torch to release bolt/nut.

Use of petroleum lubricant or solvent during tyre mounting.

Brakes’ overheat.

Electric discharge either from a high voltage line or lightning.

Fire in ambience.

Severe under inflation or overloading.

Presence of contaminants inside the tyre.

Oil or other combustible fluid ‘absorbed’ by the tire.

If we now go back to the original question i.e. Tyre burst or explosion during take-off, one can probably understand that we should first determine whether it is a burst or an explosion. They key causes in case of an aircraft would be:

These are also the reasons why ‘Nitrogen’ inflation as well as disc brakes is mandatory on Aircrafts.

Question
Just went through your article on ‘Engine life’ and was curious about the line ‘Maximum dry CR 13.5 kg/cm @ 400 rpm’. I assume ‘dry’ means cranking the engine without allowing ignition to take place and ‘CR’ means compression ratio, but what does the figure 13.5 kg/cm stand for? Is it pressure (i.e. kg/sq. cm)? VG/Mumbai

Answer
‘Compression’ Tests are of 2-types - i) ‘Dry’ meaning as done below and - ii) ‘Wet’ meaning after injecting a 10-20 ml of engine oil thro’ the spark plug opening ‘before’ cranking the engine for the test. Ideally speaking, in a healthy engine, there shldn’t be much difference between the two. However, if the piston/rings are worn out, there will be significant difference. So a ‘wet’ test is a sort of double check before concluding that the p/r’s are gone.

It’s a std procedure when taking the ‘compression’ readings to - i) remove all the spark plugs/Air Filters, ii) depress the Accl Pedal fully and iii) crank the engine by the starter motor, which is usually 400 rpm per typical petrol engine starter motor design, till the pressure gauge screwed in place of a spark plug/cyl registers a max reading (2-fellows needed). The PG used is a ‘Stay-Put’ type, like a Tyre Pressure Gauge, which permits one to read it accurately and then ‘reset’ to zero.

The fig ‘13.5′ is - i) the ‘pressure’, either in psi or kg/cmsq here, recorded by the PG used as above and ii) ‘13.5′ is the fig for a healthy engine having a compression ratio of 9:1 - as per Suzuki Work Shop Manuals.

Question
Also, would the pressure not depend on the compression ratio, as well as the inlet pressure (in supercharged/turbocharged engines, this would be above atmospheric).

Answer
Obviously it’ll be higher for engines having ‘Compression Ratio’ higher than 9:1. At 400 rpm, atleast a Turbo Charger will have no effect coz the engine is prevented from firing by removal of its Spark Plugs and in a Super-Charged engine, the pressure build-up will be negligible at such a low rpm. May be they recommend taking off the S-C drive belt in such a case but I won’t know off hand as I’ve yet to come across a work shop manual an S-C car!

Question
Wouldn’t it also not depend on the condition of the air filter and the inlet/exhaust valves (more the fouling, less the pressure)?

Answer
As I’ve said above, the air filter is removed for such a test. I suppose valve/seat wear goes hand in hand with piston/rings wear, as far as an engine performance is concerned.

Subsequent Responses
Thanks for the very precise answers to my queries! It has improved my understanding of automobile engines. I remember I had the chance to witness a ‘dry’ test, after the garage had done a ‘carbon clean’ chemical process on my Maruti-800 a few years back.

However, instead of the ’stay-put type’ pressure gauge you mentioned, they had an instrument that took the compression readings on ‘cards’, much like an engine indicator (used in marine engines). He claimed that the improvement in readings was due to the ‘carbon cleaning’ of the valves/valve seats and pistons/rings. He even inserted a sort of probe inside the spark plug hole, to show me on a video screen the cleaned insides - an instrument similar to what ENT Doctors use to look inside one’s ears/throat! VG.

That was an interesting experience you shared with me VG. However, this ‘Carbon-Clean’ using machines for the purpose can be dicey and do more harm than good, as certain minimum carbon deposits at ‘strategic’ locations within an engine are actually necessary, to enable it achieve its highest possible/designed compression ratio. SKG.

Question
What’s the funda for an ICE’s life i.e. how much should I expect a used Honda 1.3 DX engine to last - given that it shows 42 Kkm on the odo as of now. I have heard that 1-Grand Mark is the near end of a Car engine and time for an overhaul. Would that mean I only have another 58 Kkm or so to see before I have to visit the garage for an expensive overhaul? Or does it also depend on the way one drives and maintains the engine??

Answer
A question like this is difficult to answer with reasonable accuracy. It’s some what like asking why some Guys croak at 30 and some > 75, when the average life expectancy in India is 50!

For example, I have seen any # of M800s in DLH with engines killed by 70 kkm whereas I had a ‘91 std with a Retrofit AC, driven by atleast 6-members of the family over a period of 10 yrs/144 Kkm, with engine still in full pep/nil oil consumption – to the extent none could figure out that the odo had once turned over!

For starters, consider the following extract from my Article ‘Funda’s of Automobile Engg.’

Q: What is Engine Life Factor (ELF)? How can it be calculated?

A: It’s a ‘Factor’ given by the Formula ‘ELF = 100,000/Max RPM x Compression Ratio’ of an ICE. Since it’s a ‘number’ only, it’s devised to ‘compare’ the Life and Reliability amongst comparable ICEs.

Now where does that leave one - gasping for breath or waiting to exhale!?

On the other hand, it’s been my experience, based on funda’s of A-E, that the life of a Car Engine largely depends on the following - perhaps in that order:

1) Its basic design/materials, ‘workmanship’, and OEM-QC standards.
2) How well mated it’s to the Car by way of ‘Power to Weight Ratio’ - anything below 70 is an ‘edge’ design.
3) The proverbial ‘nut behind the wheel’.
4) How well it’s been ‘run-in’ and subsequently driven/serviced/oil-changed.
5) How often and for how long it’s been driven at >75% of its max rating - rpm/bhp. Cars in India lose out on this front compared to their western counterparts that log most of their mileage in 5th gear a/a ours in 3rd - typically translating to 1.66:1 ELF wise!

It’s my reckoning that OE Engines of most present day cars with PWRs > 70 can easily do 200 Kkm+ if ‘well looked after’. However, when it comes to assessing the ‘residual life’ of a used car engine, one can go about it scientifically as follows:

A typical expression found in various W/S Manuals in respect of the ‘health’ of a 9:1 Compression Ratio (87 Octane) Petrol Engine states:

i) Max ‘dry’ CR - 13.5 kg/cm @ 400 rpm/normal Starter cranking speed.
ii) Permissible Inter-cyl variation - (+/-) 1.0 kg/cm.
iii) Wear-down/service limit - 10.0 kg/cm.

Therefore, by implication, one can predict the remaining useful life of an engine by comparing its present CR with its values under (i) and (iii) above, vis a vis its ‘true’ Odo reading at the time of such a Test.

However, this will tell you about the state of its pistons/rings and valves only and not about its various other wear prone parts, such as journals/bearings etc. Only a ‘trained’ ear can tell the latter to some extent, by listening to its ‘noise spectrum’ at various loads/speeds.

Engine oils do more than you think. It’s easy to name the main function of engine oil: to lubricate every moving part of your engine with a protective film that reduces friction. But engine oil has at least four other duties, and failure to perform them all can seriously reduce the performance and life of your engine.

First, your engine oil cleans your engine. Gasoline and diesel engines can produce soot, ash, acids, and moisture that eventually form sludge, varnish, and resins. If they collect on critical engine parts, it means serious trouble. A quality engine oil keeps them suspended until filtered out or drained away when you change your oil.

Next, oil seals microscopic hills and valleys on piston rings and cylinder walls. Without proper sealing action, you’ll lose power and waste fuel.

Further, engine oil also protects your engine against rust and corrosion.

And finally, oil cools vital parts such as camshaft, rods, and pistons that the engine coolant in your radiator cannot reach. As much as 40% of the cooling job in your engine is performed by the oil in your crankcase.

Some facts about viscosity index

The Viscosity Index or ‘VI’ measures the change of an oil’s viscosity over a wide range of temperatures. The higher the VI of an oil, the less it will thicken when cold, and the less it will thin out when hot. A high VI oil will be more effective when lubricating your engine over a wide temperature range. Changes in viscosity and VI result in different viscosity grades, so you can pick the best grade for your vehicle.

Here’s a description of the five most common ‘SAE’ multi-grade oils:

0W-30: Premium winter grade oil. Provides year-round protection and fuel economy. Can be used where SAE 5W-30 is recommended.

5W-30: Premium multi-grade oil for easier cold-weather starts, maximum protection, excellent fuel economy and added engine life. The preferred grade for most cars built after 1989.

10W-30: The most commonly recommended multi-grade oil by OEMs in India. Delivers excellent all-round performance for the average driver.

10W-40: A premium multi-grade oil for hotter-than-normal running conditions, say where ambient temperatures exceed 40°C. It’s capable of providing extended engine life under such high temperature conditions.

20W-50: Thicker premium multi-grade oil for added protection against metal-to-metal contact; specially formulated to meet the needs of high performance Engines.

Making a change for the better

Today’s engines are efficient and sophisticated machines, often using multiple camshafts, turbo-chargers and other features. They also run faster and hotter, placing tremendous demands on engine oil performance.
That’s why it is essential to follow a strict oil-and-filter change schedule for your car. Changing the oil and filter remove harmful contaminants that may build up in your oil.

A fresh supply of engine oil with its specially selected additives will restore the protection your engine needs against corrosion, gum deposits, excessive wear, and other problems.

The oil and filter should be changed at the interval recommended in your owner’s manual. Every 5000 -10,000 km or 6-12 months is a common recommendation in India, especially for the BS-III Engines.

Speaking of performance additives

Most oils look, feel, and smell the same but their performance can be vastly different, thanks in part to their ‘in-built’ additives. Additives suspend dirt, inhibit foam, improve cold-weather flow, prevent corrosion, reduce friction, and add other qualities.

Many specialty additives or oil treatments are sold separately as brand names and promise longer life or extra performance for your engine. Remember that modern oils are recipes with measured portions of ingredients. Upsetting the recipe balance could lead to problems.

An oil formula may include a little anti-wear additive the same way a cake includes a pinch of salt to bring out flavour. If a little salt works, should you add more? Probably not, and the same goes for oil additives.

Believe in choosing the best quality oil you can afford and change it according to your Owners’ Manual is wiser in the long run.

Today’s Aircrafts are a culmination of the state of art engineering know how of all disciplines – be it mechanical, structural, electrical or electronics. They more than ably fulfill mankind’s eternal desire to fly – literally around the world and in much less than 80-hours!

Present day commercial Jets have some unique features when it comes to their Tyres. For without their required ‘functionality’ AND ‘reliability’, they may perish at the drop of a hat – not to mention carrying hundreds of lives alongwith. Therefore, these two requirements take precedence over aesthetics.

Tread design of ACTs is ‘plain/rib’ type, since such patterns result in great ‘straight-line’ stability, smooth rolling, lower noise levels, less prone to irregular wear, along with very good ability in channeling out water on wet runways to eliminate loss of control while landing/take-off due to ‘aqua-planing’.

You may recall that this is similar to ‘wet’ F1 tyres. Besides, since Aircrafts do not zigzag or are called upon to traverse through soft ground, they don’t need to have Stock Car like tread patterns.

Tread rubbers of ACTs (as well as F1) tyres have to have great braking efficiency and high temperature withstand abilities. As a result, unlike Stock Cars, durability takes a back seat here. Besides, ACTs have also to face extreme operating conditions, such as:

1. They have to withstand very wide range of temperatures and that too within a short span of time. For example, at a cruising altitude of 10,000 meters, their ‘hold’ temperature can be low as (-) 45°C. Within half an hour or so upon ‘approach’ to landing, it changes from this to near ambient at ground level. And soon after ‘touch down’, their tread surface can rise to (+) 250°C or more! And nearly the same is true in reverse after a take off!
2. Load on an ACT is around 25-30 tons ‘per tyre’, as against a typical SUV @ ~800 kg per tyre and a typical truck @ ~ 4-6 tons per tyre.
3. Consequently, ‘inflation pressure’ in an ACT is very high. For commercial jets, it’s around 220 psi, as against 30~35 Psi of a stock car. For such reasons, ACTs (and F1’s) are filled with pure nitrogen out of necessity and this philosophy is trickling down to demanding stock car users as well.
4. The takeoff speed of an Aircraft depends on many parameters such as its ‘laden-weight’, the ambient air temp/density, wind direction/velocity etc. The take off speed of common jetliners these days is around 300 km/h and landing around 240 km/h.

Apart from the above/extreme operating conditions that ACTs have to withstand, their manufacturers have to keep their weight to minimum possible so as to minimize the aircraft’s fuel consumption. This is far from easy and one of the reasons why so few Companies around the world successfully produce ACTs to today’s demands. Because of such extreme requirements and limited tread depths, ACT tread wear’s are much faster and surprising as it may seem, it’s viable to ‘re-tread’ them today, as opposed to ‘Not Recommended’ for Stock Cars.

Accordingly, ACTs are sent for retreading after around 350 landings for Radial and 200 landings for Bias Ply tyres. On an average, a Radial ACT can be retreaded upto 3 times (350×3=1050 landings) and a Bias type upto 6 times (6×200=1200 landings). Quite like Stock Cars, Radial ACTs are preferred due to better rolling resistance, traction and the fact that they offer almost 150% higher number of landings between retreads.

However, unlike conventional retreading techniques, retreading an ACT is a highly evolved task. For example, after a retread, their balance and uniformity in all the domains has to be checked such that it conforms to the ‘original’ spec again. It’s for such reasons that leading ACT mfrs have plants dedicated just to retreads.

To conclude for present, it may interest you to know that the worlds most advanced commercial jetliner as on date, the ‘Airbus-A380’ has 20 nos tyres of size 1400×530R23/40PR in its rear under carriages and 2 nos 1270×455R22/32PR for the nose. Bridgestone Japan is the chosen vendor for these, producing them at their Plant in Kurume, Japan.
And, for a change, I’ll ask readers a question this time. Most of you may have read of ACTs bursting at take off, also. WHY? If you know the answer, e-mail it to expert@indiaautomobile.com ALONGWITH your full name and address. The correct ones received by Sunday the 16th March ’08 will be published in these columns next week i.e. Friday the 21st March ’08.

Fuel used in F1 Cars
No specials fuels are used – only Unleaded/‘Green’ Petrol - similar to that available at our roadside filling stations. It has to comply with the strictest EEC standards concerning pollution. At one time, the fuel used in F1’s consisted of a mixture of hydrocarbons and was a very special fuel, which bore little resemblance to commercial petrol. The FIA thus introduced regulations with the dual aim of not only steering the oil companies’ research in the right direction so that it would benefit the ordinary motorcar but also significantly reducing motor exhaust emissions.

Tyre Changes per Race
The present FIA Regulations stipulate that each driver may use a maximum of 32 dry-weather tyres (40 in 1998) and 28 wet-weather tyres throughout the duration of an event. Each driver may use a maximum of two ‘rubber specifications’ for his dry-weather tyres during free practice, but he must designate the rubber specification he wishes to use for the rest of the event before the start of qualifying practice.

Thus, the maximum number of tyres he may use for qualifying practice, the warm-up and the race is 28 (14 front and 14 rear), chosen from amongst the 32. The Scrutineers, who are also responsible for checking that no driver exceeds the maximum number of tyres allowed, identify all of these tyres by means of an FIA-supplied bar-code system.

Refuelling during a Race
It is allowed but not obligatory. It must be carried out with the refuelling equipment specified by the FIA. The system is based on aviation equipment and complies with all the other safety requirements laid down by the FIA.

Speed Limits
Strange though it may seem, yes, but only in the pit lane, where the speed limit is either 80 or 120 kph (50 or 75 mph), depending on the circuit and the configuration of the pit lane. There are electronic devices checking the speed of the cars along the whole of the pit lane. If a competitor exceeds the limit during a Race, he is usually penalised with a time penalty whereas if he exceeds it during a practice session, he is usually fined ($ x km).

However, as in everyday life, the severity of punishment is proportional to the seriousness of offence, and also takes repeat offences into account. To avoid this, most Constructors equip their cars with a speed limiter, which the driver has to activate (usually by pressing a button on the steering wheel) as soon as he enters the pit lane. However, sometimes drivers forget and thus end-up paying a penalty!

Weighing of F1 Cars
The Scrutineers may weigh the cars any time, to make sure they never weigh less than 600 kg, including driver. Electronic weighing devices are located at the entrance to the pit lane to enable these checks. During qualifying practice, an electronic programme selects at random the cars which are to be checked. When a car is chosen by the computer, a red light comes on and the driver returning to his pit must proceed to the weighing area. If the weight of the car is insufficient, the driver could be excluded from the event, but he has the right to request that the car be weighed a second time.

To avoid cheating, any car that breaks down on the circuit is made to pass in front of the computer, which decides whether it must be weighed in the same condition. At the finish of a Race, all the cars are directed to the ‘parc de fermé where they are weighed. The drivers are also weighed separately before proceeding to the podium or to their motor-homes. If a Car+Driver weight does not comply with the 600 kg limit at the finish, it maybe excluded from the classification. This has happened in the past.

F1 Engines
The engine of an F1 Car is the most complex piece of equipment that goes into it. It consists of close to 5000 parts of which around 1500 are moving elements. When all of these are meticulously put together after about 2-weeks of work, it can produce more than 750 hp and reach rpm’s higher than 20,000! At their maximum pace, the current V8 engines consume around 60 litres of petrol for 100km of racing.

While manufacturers could easily continue to develop more powerful engines within the 2006 Regulations, the FIA felt that such unnecessary costs should be avoided and thus ruled a freeze on engines’ basic specs as of the 2007 F1 season. So instead of a yearly 20 to 30 hp gain, the manufacturers cannot develop their engines further and are now imposed with a rev limit of 19,000 rpm.

At the end of 2005, the last season where the regulations allowed 3-litre engines with 10-cylinders, some engines were producing more than 980 hp and running very close to the 1000 hp mark, a figure that was never reached since the ban on turbo engines. It was thus a sign for F1’s governing body to change the Regulations, as top speeds of 370 km/h reached at Monza were deemed hazardous for the drivers as well as the spectators.

Starters for F1 Cars
As per FIA, an electric starter has not been obligatory for several years and teams choose not to fit one in order to prevent an additional source of energy/Battery from causing incidents such as a fire or explosion. They are, however, authorised to use a portable starter in front of their pits and on the starting grid, but if a driver stalls on the circuit during the race, he has to retire, even if the car restarts once the marshals have pushed it away from a dangerous position. Most cars nowadays are, however, fitted with sophisticated electronically controlled anti-stall systems.

Gearboxes on F1 Cars
’Automatic’ gearboxes are prohibited by the FIA. However, all the cars are equipped with semi-automatic gearboxes where to change gear, the driver no longer has to activate the clutch pedal at the same time as the gear lever. He simply presses a button on the side of his steering wheel. There is a button on each side: one for changing up, the other for changing down. He, therefore, no longer has to take his hand off the steering wheel also and such a electro-hydraulic device allows the driver to change gear in one or two hundredths of a second, which is unquestionably faster than with a conventional system.

Number of Gears on F1 Cars
The rapid changes possible with semi-automatic gearboxes mean that transmissions with a greater number of ratios (six or seven) can be installed. On circuits with a large number of bends, the drivers only use four or five ratios. Reverse gear is obligatory, but must not be used in the pit-lane.

Brakes of F1 Cars
The brakes on stock cars these days are derived from the ‘disc brakes’ which were first used in racing. All F1 cars nowadays are equipped with brakes with calipers made from light alloys while the discs and pads tend to be made from synthetic materials, i.e. carbon/carbon, as their resistance to heat is much greater than that of stock car brakes and they weigh significantly less. Which is why under certain conditions, the insides of the F1 wheels appear completely incandescent!

The braking power of an F1 Car is uncommonly high. At the end of a ‘straight’, at speeds around 340 kph, an F1 car can brake in less than 100 meters in order to take a slow corner. Naturally, carbon/carbon is expensive. It takes six months to produce a disc, at temperatures of between 900 and 2000°C. The same material is now used to produce clutch discs.

Next week we’ll talk about the fuel they use, refuelling during a race, no. of tyre changes allowed, their speed and weight limits etc.

How did it start
There was no ‘formula’ for motor racing during the years 1894, when the first ‘organised’ motor race took place from Paris to Rouen, until 1900. The then existing vehicles were simply raced. However, a differentiation was made between those cars on the basis of their method of propulsion (petrol or steam), and their number of seats.

During that time, cars always had at least two seats and it was not until the end of 1920 that single-seater cars were used for racing. The ‘invention’ of the rear-view mirror made an important contribution to this development, since one of the mechanic’s tasks in the 2-seaters was to warn the driver that someone was trying to overtake him!

When the first F1 race took place
The ‘FIA Formula-One’ World Championship was created early in 1950 and its first even was held on 13th May 1950 at ‘Silverstone’ Tracks in the U.K., which continues to be one of the most sought after ones even these days.

Participation Criteria for a ‘Constructor’
A prospective ‘Constructor’ must submit his entry to the FIA, providing evidence that he is both the ‘Designer’ AND ‘Constructor’ of the ‘Chassis’ of his car. He also has to substantiate sufficient technical and financial resources to take part in the Championship. A ‘Constructor’ need not be its engine manufacturer also and the name of the chassis manufacturer is always given before that of the engine manufacturer. In the event of winning a Championship, the title is awarded to the Constructor/Chassis manufacturer.

Drivers of F1 Championships
To qualify to participate, a Driver must hold a ‘Super Licence’, which is awarded on the basis of his past record in junior formulae races and of his having a valid contract with an F1 team which has entered the Championship.

How long does an F1 Race last
The distance is the least number of ‘laps’ which exceeds 305 km, and no race may last for more than two hours. On certain slower circuits (such as Monaco), in the event of rain, the Clerk of the Course is sometimes obliged to stop the race after two hours.

The Race continues whether rain or shine
An F1 event takes place in all weather conditions and tyre manufacturers have developed treaded tyres, which help to avoid the risk of aquaplaning. Nevertheless, the Race Director has the power to stop the event, if this becomes necessary for safety reasons as apart from track-grip, the greatest problem during rain is visibility, which is significantly reduced due to the spray thrown up by the cars’ tyres. In order to counteract this problem, the cars are equipped with a red light at the rear, which must be switched on if it starts to rain.

How Powerful are F1 Engines
Present F1 Regulations peg their engine capacities to 3.0 Lrs/19,000 Rpm. Turbo or Super Charging is not allowed. Even though the Constructors refuse to divulge details of their engine power, it is rumoured that nowadays their maximum powers exceed 800 Hp. Manufacturers of engines with eight or ten cylinders opine that maximum power is not always the most important factor. The ‘shape’ of its ‘power curve’ also matters, which in their case is better at a low engine speeds. Having ‘adequate’ power at lower engine speeds is of equal importance, especially on slow circuits.

Speeds F1 Cars can reach
The highest average speed of 242.615 kph achieved in Italy during 1971, that was won by Peter Gethin. Recent computer simulations suggested that current F1 cars can achieve an average speed of well over 300 kph. David Coulthard set the highest ‘straight line’ speed at 356.5 kph, recorded during the 1998 season.

Contrary to what I said last week, I’ve just realised that I’ve already written about the importance of Wheel Balancing AND Alignment during the month of August ’07 itself. For those who tuned in later, please browse thro’ www.indiaautomobile.com/articles/archives/August.

So this week, let’s talk about other related issues, such as ‘Steering Wobbles’ and ‘Steering Rattles’…

Steering Wobbles

These are basically a) those occurring at cruising speeds and b) ones that occur at slower speeds, such as at take off and braking. While the former can largely be attributed to ‘dynamically-unbalanced’ wheels and to a lesser degree to ‘wheel-alignment’, the latter are caused by different reasons, such as – i) Unevenly worn front Tyres, ii) Out of true Wheel Rims, iii) Internally Damaged Radial Tyre Casing, iv) Worn-out Steering/Track Linkages/Suspension Bushes/Members, v) Damaged ‘Knuckle’ Joint, vi) Damaged Wheel End Axle Assy, vii) ‘Out of true’ Front Disc Brake Rotors, vii) Faulty/Worn out Caliper Assys OR sticky Hydraulic Piston/Rings thereof and viii) Defective Engine/GB Foundations, etc.

Steering Rattles

The real crunch here lies in identifying the source of such rattles as more often than not, with wear and tear setting in, a steering rattle gets sort of ‘progressive’ i.e. it can ‘shake’ other members of the ‘system’ into rattling which on their own may not! Such rattles can originate from one or more parts of the steering system as a whole.

Here’s how one can systematically analyse them, as those caused by – i) Premature wear of Tie-rod end/Rack ball joint: These can set in by ignoring the need to have all the five Wheels in good ‘dynamic balance’ all the time. This can be checked out by hoisting the vehicle on a 2-post lift and ‘yawing’ each front wheel horizontally - to ‘feel’ if there’s any slack around them; ii) Rack and/or Pinion wear: This again is a consequence of neglecting to keep one’s wheels in good balance all the times. These can be checked out by – a) parking the vehicle with wheels ‘st-ahead’ on a level ground and b) standing out side the driver side, gently rocking the steering wheel to the left/right. If there’s no slack per (i) above, then a slight steering wheel motion will reflect in front wheels’ motion also. If it doesn’t, it’s an indication of excessive slack between the rack and pinion. If it cannot be rectified by suitably tightening the rack ‘damper-bush’, the only remedy is to replace both with genuine parts at one go; iii) Rack ‘Bush’ Rattles: These are ‘softer-sounding’ in nature and can be pinned down by – a) parking the car on a level ground with engine off and b) ‘rocking’ the stg wheel gently. If one can hear soft thuds from the LHS end of the car even while sitting in the driver seat, the rack bush is the culprit and the only way to get rid of it is to replace with a genuine spare part; iv) St Column Rattles: These are relatively easier to identify as their origin is close by and one can hear them as ‘metallic’ in nature – may be extending upto the pinion. Since most Cars’ steering columns these days have ball bearings at its both ends, the main culprit of such noises is invariably the one or more of the ‘universal joints’ deployed between the steering column and the rack-pinion. This can be set right by getting the stg column suitably ‘tensioned’ at a skilled Garage.

With the foregoing trouble-shoot, most steering rattles can be overcome with lasting success. If not, one is left with no choice but to have one’s steering system suitably overhauled, including replacement of ‘all’ the wear prone parts at one go.

Cutting corners here is not advisable since a half-worn part which was otherwise ‘silent’ will now start rattling due to greater thrusts on it from the replaced/new parts!