Car Service

Performance tyres, selection and tyre tread patterns.

2009-11-02T19:12:00.000-08:00

Tyres (USA spelling = Tires) and wheels – a cheap tyre can reduce your ability to corner on a dry surface by as much a 10-20 mph in the wet this difference can be much much greater. Most performance tyres (USA - Tires) are best in the dry.

Ideally you should have a dry and wet weather set of tyres (Tires) and change them in the morning – realistically for the Northern Hemmisphere you should bias toward wet weather tyres (Tires) . Soft racing spec tyres give the best grip but wear very quickly. A directional ‘v’ tread pattern seems to give me the best compromise between driving in the wet and dry.

Asymmetric tread is designed with a different pattern for each corner of the car to maximise control although they all need replacing at the same time and some cannot be transferred front to back or axle to axle.
Cornering speed can vary immensly depending on tyre selection and surface conditions.

Modern cars come with recommended tyres (not just sizes but makes and models) – stick to these and you will be ok. Never have different tyres on the same axle. New tyres should generally go on the rear to prevent over steer problems and try to get the same or very similar tread patterns for the front and rear.

Bear in mind that tyres tested as the best on track could be the worst on road. Tracks are smooth and our roads are full of ruts and potholes the tyre may bounce or just create a harsh and noisy ride (my recent tyre change stopped most of the annoying in car rattles I was getting!)

Tyre pressures also have a profound effect on handling – keep them up to the manufactures recommended pressures for the speeds you are driving at and the car will handle predictably and the tyres will last. Check them visually every day and check pressure weekly.

Regular loss of pressure can be caused by a puncture, a faulty valve, a split in the wall of the tyre or heavy driving so get a suspect tyre checked properly. Driving with the wrong tyre pressures is as illegal and dangerous as driving with under the minimum tread depth.

The wheel should also be balanced (I recommend yearly as the tyre tread wears down and the alloy receives little knocks and scrapes) to maintain full control over the car and optimum life of tyres and brakes – the wobble of a wheel at high speeds can also damage other components near the wheel like brakes and suspension so get it checked properly.

The best grip in the dry comes from a slick tyre, one with no tread pattern whatsoever. This is illegal for road use as these are extremely dangerous in the wet. A good compromise is a tyre which has large rubber contact areas. These often have a diamond style cut.

V grooves are good allround tyres and although these do not give the best grip in corners they were voted best tyres by drivers using them due to the predictability of the handling. So often the on-paper results of tests are quite different from the real life feel of the tyre. Most rims can take tyres that are a little wider than standard and as the contact area is increased the grip is also better.

Tyre prices vary considerably and this should be taken into account when buying a rim. Often a slightly larger profile can save as much as £200 per tyre! So make sure you don't end up with a really rare size, as a premium, will always be attached to the price and many tyre specialists will have to order in stock when you need a replacement.

Punctures are a real pain but it is worth bearing in mind that these can be repaired if the damage is in the central third of the tyre tread area. Inner tubes cannot be used in tubeless tyres due to the ridges around the inside of the tyre - which rub on the tube wearing it away until the tube eventually blows.

Damage in the side-wall of a tyre can mean a serious accident is looming if there is a blow out. Always avoid rubbing the tyre against the kerb when parking and check for damage frequently. If tyres need regularly inflating then suspect a puncture. Punctures can easily be detected using a strong washing up liquid mixture and pumping up the tyre. Bubbles will form in the area of the puncture (it's also worth checking the valve as well as these have been known to fail).

NB: DO NOT RUN THE CAR ON A FLAT TYRE AS THE RIM MAY BECOME PERMENANTLY DAMAGED - THE TYRE SHOULD ALSO BE DISCARDED AS POTENTIALLY DANGEROUS.

http://www.torquecars.com/tuning/performance-tyres.php

Sports exhaust design and performance gains.

2009-11-02T19:10:00.000-08:00

The job of the exhaust is to break up the sound pulse from the engine, muffling the sound and allowing the exhaust gases to escape efficiently.

We see the young lads fitting drainpipe size exhausts and will examine the cause of power losses in these cases.

What effect do they have on the engine and do all exhausts increase power?

This component affects the Blow phase of combustion - getting rid of the exhaust fumes is important and the less pressure there is in the exhaust system the higher the BHP produced.

However the rate of flow or velocity of the exhaust gases also comes into the equation. Big exhausts slow up the flow and smaller ones increase it. You have to balance the exhaust with the intake and engine capacity to give the best flow rate without causing backpressure (a delay of exhaust gases unable to escape quickly.)

Ideally you will have a different bore size for each RPM band in the engine, but this is not practical, so an optimum all round setting is selected. Most good quality performance aftermarket exhausts move the optimum to work more effectively at higher RPM.

Interestingly some performance car makers have a "dual bore size" exhaust which varies according to the RPM allowing low down Torque and better peak power figures.

Polishing the inside of the exhaust will aid the fast exit of gases as there is less internal friction.

We hate to see street cars with massive exhausts and we hope the following suggestions will help common sense to prevail. Typically the exhaust is based on the amount of air an engine needs to expel and this varies greatly in turbos and highly tuned engines.

As a very very general rule of thumb, under a 1.6l engine, TorqueCars recommend you stick with a maximum 1.5 to 2 inch pipe (the smaller the engine the smaller the bore size). Under 2.5l engines go with 2-2.5 inches and over this go with a 3 inch exhaust.

Over 2.5 litre engines we would suggest a twin exhaust system using half the engine size to determine the optimum pipe size as we have just outlined. so a 3.0 Engine would be ideally suited to a twin 1.5-2 inch bore and 5 litres with a 2-2.5 inch twin bore.

This bore size applies to the minimum bore size throughout the length of the exhaust right up to the back box and tail pipe.

(The back box & exit pipe can be a little wider but this will not release more power, it will just give a deeper sound.).

Gases flow better from a large pipe to a small pipe if the join is cone shaped. Steps will cause turbulence and this can interfere with the airflow and affect performance.
Bigger exhausts will actually slow up the flow of gases, there is an optimum size to give the best flow rate but resist backpressure where the exhaust gases are constricted. If you can get your fist inside - it's too big!

The shape of the exhaust manifold (painted red in picture) is also critical as is the primary and secondary length. This is something best left to the experts to calculate – most manufacturers do a reasonable job. Aftermarket performance exhaust headers will obviously be better.

However you can improve a standard exhaust by smoothing out the inside with a grinding wheel on a drill. Alternatively buy a purpose built stainless steel unit for your car.

The best systems for a street car are called 4-2-1 which means they go from 4 pipes into 2 pipes and then into 1 in a 3 step process. This will maintain some lower RPM torque. Some very high performacne exhausts are 4-1 where all the pipes merge at one point lower down the manifold or 4-2 with two exit pipes. These exhaust allow higher peak power figures and are best suited to a very high average RPM band for example on race cars.

A larger diameter exhaust means that as the pressure needed to expel the air is lower the whole process will be quicker with a lower push needed. Cats suck power a little by slowing up the airflow. Catalysts are sadly a requirement on today's cars, there is a typical reduction of 1-4 bhp overall.

If you find a high flow sports cat or use an off road only de cat pipe you will notice an improvement on most applications. Although this benefit will be very minimal on smaller engined cars. There is little differance between a sports cat and a decat and some high performance cars already come with a good quality sports catalyst.

Another option is to go for a 4-2-2 exhaust where you have twin exit pipes with 1 for 2 exhaust ports from the engine.

Most sports silencers add a deep roar to the exhaust but this adds little to the overall experience other than the noise they make. One of the best exhausts I ever had was a standard one (from a larger engined car) with the rear silencer remover – the centre expansion section was larger to help muffle the sound but it really improved flow a lot and sounded great. I will note that low down torque was lost with a noticably higher peak rpm torque band.

TorqueCars recommend the "Cherry Bomb" for simplicity and a deep throaty sound but you will probably need to fabricate your own mounts.

Just as induction length is critical so exhaust length is also vital. You should also aim to have the same exhaust length from each exhaust port.

Most standard exhaust headers (or depending on your location manifolds) are cast and have many imperfections on their internal surface. They often have ridges where surfaces are joined. Grinding and polishing the inside of the exhaust smooth will aid airflow and improve things.

While you are at it you could polish it throughout its length to completely remove resistance. Performance exhausts are made of stainless steel which has a much smoother internal surface and is also much lighter. Attention should be given to the joins and bends, and the fewer the better being the order of the day.

Under bonnet temperature is one of your biggest performance killers see the induction and vents articles for more suggestions. Wrapping the exhaust manifold with a heat resistant wrap can yield a dramatic reduction in temperature and will help the cat to reach operating temperature more quickly therefore prolonging its life and efficiency.

(Don't use cloth bandages as this becomes a fire hazard!) The application of a ceramic coating can substantially reduce the transmission of exhaust heat into the engine bay and will keep get the catalyst up to working temperature more quickly.
Removing your cat from the exhaust

To find out more about exhausts in general, or to ask which exhaust application would be best for your car, join in the friendly banter in our members forum and discuss exhausts in more detail (and all aspects of car modification).

http://www.torquecars.com/tuning/sports-exhausts.php

Uprating brakes is an essential modification. (brake kits)

2009-11-02T19:08:00.000-08:00

Brakes – part of going fast requires that one is able to stop as fast.

The brake works with a friction pad, which is pressed against a Disc – the friction converts the momentum of the car into heat which is then dissipated over the brake disc slowing up the car.

Heat is a big problem with heavy braking and a racecar must be prepped to cope with the high heat demands placed on the braking system.

The braking force goes from the pedal into a magic box called a servo, which uses engine power to amplify the pressure of your foot decreasing the effort you need to expend.

The pressure is transferred to the friction pads by means of liquid (brake fluid) inside a tube. At the brake pad end, which is subject to high temperatures, the fluid itself can get very hot.
When making the car go faster you must make sure you can stop it faster too!

The benefits of using a liquid, which cannot be easily pressurised, means that the effect of braking passes along the tube (brake pipes) almost instantly. A cable would stretch a little and needs constant adjusting – most handbrakes use a cable system so you are aware how inefficient the cable brake system is also cables are more susceptible to the effects of heat and stretching.

The problem with brake fluids are that they are hygroscopic (they draw in water particles) which reduce the effectiveness of the transference process also at high temperatures they can boil – bubbles of air in the brake fluid create a spongy effect at least or at worst can completely prevent the brake from having any effect. (See the article on Brake Fade for more details of this phenomenon and how it can be avoided.)
Vented brake disc

The heat is dissipated from the pad by the discs – a vented disc has a central channel which increases the surface to air ratio of the disc and created better and faster cooling.

Drilled discs also increase the air ratio and along with grooves help to prevent a gas build up between the pad and the disc and keep the pads ‘clean and sharp’.

Bigger discs = better cooling but bigger discs may require a different style of alloy wheel.
Brake pad selection.

The pads though are an essential part – the higher the friction the better.

Racing pads are specially constructed from a high friction compound which works at much higher temperatures.

A true racing pad will start working effectively only when it gets hot so this renders race spec pads useless for the road where braking most often happens on cold pads.

TorqueCars have found that fast road pads such as those supplied by Pagid and Black Diamond are a very good compromise and some makes of performance pads have the added benefit of producing nearly zero brake dust and even last longer than the standards pads I was using – although driving style will effect the wear on the pad and on your discs.

ABS helps to prevent lockups under heavy braking and allows you to steer the car but steering will reduce the braking efficiency as the ABS cuts in more. ABS on gravel and snow can actually be a problem as the brakes are cut due to loss of traction whereas if the wheels where slowed a little the car could stop more quickly.

Rally cars have a custom ABS setup which is quite different to standard road cars and maintains control and braking efficiency on gravel surfaces. If you are not a competent mechanic Torquecars recommend that you leave brake work to the specialist as a failure would result in a certain accident.

Brake upgrade kits.

There is much that can be done to upgrade the cars braking system. Key areas for attention are fitting bigger discs. As a larger disc will have a bigger friction area and be able to dissipate more heat you will benefit immediately. You will also notice you have more feel and it is easier to detect the point of lock up with a large disc conversion kit. Taking a standard family car with relatively small discs, as an example, an easy and cheap route would be to visit the breakers yard and get brake disks and servos from a performance model from the same family. For example a basic 1.1L car will usually upgrade to the 1.8 GTi brakes (you may need to upgrade the wheels at the same time). And often small cars share similar part specifications to the larger executive counterparts so a little research and chatting with our forum members will point you in the right direction.

Brake calipers and pistons next come in for attention. More pistons equal a greater clamping force and allow the use of much larger pads. Torquecars see little point of adding more pistons to a standard size disc as the heat dissipation ability of the disc will be impaired by the larger pads used. When upgrading the discs you should also look into increasing the pad, caliper and number of pistons for best effect.
General maintainance & care.

When driving through floods apply the brakes briefly to dissipate the water and grease that gets on them and this will dramatically improve your chances of stopping in an emergency situation.

Once a year or if you notice the brakes losing their effectiveness you should rough up the disc surface with abrasive steel wool or similar. This will brake the glaze and help the pad to bite the disc more effectively. You should always check your pads for wear and if you are preparing for a track day Torquecars recommend fitting new pads as these will take a lot of abuse. Check the brake discs for wear by measuring the diameter and ensure that a wear ridge is not appearing on the outside. Thin brake discs can warp or under heat stress can brake causing a wheel lockup so it really is a false economy to run with worn discs.

Brake fluid should also be frequently checked and changed annually to bi-annually depending on your driving style and the recommended service interval for your car.B rake fluid should be checked ideally by a specialist for its boiling point which gives an idea of its degradation. Synthetic (dot5) brake fluids are not hygroscopic and have extremely high boiling points. Stainless steel braided hoses prevent any flexing and therefore loss of pressure at the pad end, they also look nicer and theoretically last longer too – get a full set and do front and back at the same time.

http://www.torquecars.com/tuning/brake-mods.php

Which headlight bulb should you choose?

2009-11-02T19:05:00.001-08:00

Headlights The headlight bulb went the other day. In most cars I can ignore this until servicing time or the next MOT. I know a lot of other Torquecars members will have a go at me for this but I am often too busy to get involved with changing bulbs and I still have a driving lamp on that side anyway. However in my Audi it is not possible to ignore this, each time you turn the lights on the car will beep a warning message at you and patronise you for your entire journey by showing you a picture of an amber bulb with an X through it.

Normally I wouldn't mind but I had changed the bulb recently for a spare, which I obtained from a headlamp assembly I purchased from a scrap yard. Sadly though this only lasted a couple of weeks so I had to go to a shop and actually buy a bulb.
Which headlight technology is best for your car? What is the difference between Xeonon, halogen and HID?

There was an amazing selection to choose from. When confronted with choice we humans usually make silly decisions and go with the cheapest or most expensive option or just altogether give up and leave the shop.

I resisted the urge to do the latter and went over the options open to me. There were bulbs that were 40% brighter than normal ones at twice the cost. Then there were bulbs which had a bluish hue and claimed to run at the same temperature as HID lamps at a similar price to the 40% brighter ones. (Having tried these before I was disappointed that the light emitted did not have a the bluish hue the packaging had subtly implied but not actually stated!) Then there were bulbs that were 80% brighter than standard.

I would guess that with a fixed wattage going in the brighter bulb would be more efficient and emit less heat and more light. I was also hoping for the brightest light I could get. Then the top shelf caught my eye. It had super high wattage bulbs on it. Peaking at 80W of pure light they seemed to offer everything I wanted. Sadly though after reading the packaging I determined that these were only legal for street use on cars registered 100's of years ago.
History of headlight bulbs.

Almost as soon as the motorcar was invented the headlight appeared. Early ones were in a fixed headlight unit so the whole thing had to be changed. They used Tungsten filaments and this was actually fairly inefficient. Heat output was high so light output was much lower. The light given off appears to be yellow because it is at the lower end of the light spectrum. The filament also burns out slowly over time so as it gets older it gives off less light.

Then we had a breakthrough in Tungsten Halogen technology. Now over 30 years old this technology has been refined and perfected to give us the range of bulbs we have today. Early bulbs were made of heat resistant Quartz and then later bulbs were made from heat resistant glass. The gas used is generally Argon although called halogen in this application! These bulbs can burn longer and hotter so are able to give off more light giving it a whiter appearance. The brighter you go the whiter the light gets. Modern lights now use Xenon/halogen gas mix which enables the filament to last longer.

HID is the new kid on the block and sadly most upgrade kits are not legal. These take a few minutes to reach full light intensity although they obtain 70% brightness within a few seconds. In the UK cars need automatically levelling headlights to make these legal. These lights give a bluish/purply hue do to the light frequency they emit. HID was not an option open to me so I will discuss HID headlights in another article in more detail.
So what did I go for and was it worth the money?

It is annoying keep changing the bulbs for MOTs and having other drivers flash you so I opted for the 80% brighter ones and set about proving to myself that they were worth the 3 times the cost of a standard bulb. I replaced the bulb, but this time round it only took a few seconds. This was probably due to the fact that I had loosened up the housing and connectors last time plus the knowledge I gained on which orientation the bulb required to clear the battery and other components.

I then did a very thorough scientific test. Leaving the standard bulb in the other light and cleaning both lenses to establish a matched control group I turned on the engine and switched on the lights. Then I got out of the car, walked a hundred paces and turned round to inspect the bulbs. I really shouldn't be so cynical. The new bulb was clearly brighter than the other one. As I moved from left to right and then moving in closer I continued to check for brightness and my original conclusion was right. The new bulb really was brighter. It is hard to judge 80% brighter by eye so perhaps I will get my cameras light meter out and take some measurements.

http://www.torquecars.com/articles/headlight-bulbs.php

Fine tuning your suspension setup for your driving style.,Bushes (bushings), Toe, Roll

2009-11-02T19:02:00.000-08:00

Many people just concentrate on lowering the car and assume that stiffer springs and the lower ride height will improve handling.

However there are many other settings for your suspension which can make a massive difference to the handling before you even think about changing components.

The shocks are generally a piston inside a liquid and some have an additional gas chamber to absorb shocks (gas compresses whereas liquid does not compress under pressure.)

Shocks can have a fairly complicated structure.

Testing the shocks on your car you bounce the car – if you get more than one bounce then your shock are on the way out.

Without shocks the car would drive like a thing on a spring and just bounce everywhere.
Fine tuning your suspension settings can dramatically increase cornering OR straight line stability.

(Damper – the shock absorber).
Bound & Rebound settings
This is the dampening force of the shock absorber. Bound is the rate at which the shock allows compression and rebound is the rate at which the shock releases the compression.

If your suspension has a dampening control then you can play with these settings and get the optimum setting. Electronic in car adjustments is now possible and if you are considering drifting your car you really should invest in one of these set-ups.

Camber
This is the angle of the wheel to the road. If you put all of your weight on the outside of your feet you would have a positive camber and if you rolled your feet inwards so all your weight is on the inside you get negative camber.

As the car rolls into a corner the camber can make a big difference to handling and also tyre life. Sadly the best camber setting for handling will cause premature wear to the tyres!

Front wheels are set up to get negative camber as the wheel is deflected up. The camber setting is the angle of the wheel to the road as well as the angle of the wheel to the chassis. As the car corners and rolls the suspension geometry must maintain the best angle of contact of the tyre to the road.

This is why manufacturers go to such great lengths to set up their cars correctly and when you make suspension modifications it should be your aim to keep as close to the makers spec as possible. Generally the more tuned the suspension set-up the less variation there is under stress and the less room you have to play with. Start off with the manufacturers settings and alter these slightly increasing the negative camber and test the results. If you can’t feel any difference then why are you bothering!

Remember that kerbing wheels and hitting bumps can knock out the camber setting. Tyre temperature alters the camber so the camber is best set with warm tyres!

Caster
Imagine it is a windy day and you lean forwards – your legs now have a negative castor. The angle of the wheel hub in relation to the suspension arm is described as the angle of castor. The positive castor keeps the wheel straight when going along – a bit like a pram wheel the connecting arm to the hub is set slightly back. Stability results whereas a neutral camber would result in the wheel wobbling around the axis. The angle a car wheel is set at generates more camber when the wheel is turned.

Toe
Stand like Charlie chaplain with your heels together and your toes out. Now imagine your cars tyres are at this angle too – this is known as Toe Out. Toes in is where your heels are apart and the toes are together. Obviously the angle of Toe in a car is barely perceptible.

The effect of this setting on the car is stability – toe in gives great stability on the straight and the car resists a turn to the right or left. Toes out gives a much quicker steering response. Toe in is a road car setting and Toe out is a track setting – it is up to you to decide how much Toe you want. Toes applies equally to the rear tyres although they are generally set as a lower angle than the fronts.

Roll
Eliminating roll in corners helps cornering stability and keeps all four wheels on the ground. When pushed really hard most production cars will lift a rear wheel of the ground and when cornering you really need as much rubber in contact with the black stuff as possible.

The roll bar also known as a sway bar helps to keep the car level in a corner by taking the lift from one side and trying to move it to the other. As this is not possible the lift is effectively pulled down and everything is kept in contact with the road.

Strut braces stiffen the top of the suspension mountings and help reduce flex when you are pushing the car hard so also have a minor benefit at reducing roll.

Spring stiffness
If the springs are too stiff the car will bounce over humps and lumps in the road.

If it is too soft the car will just wallow along (it’ll be a really comfortable ride though).

The best shocks are adjustable on the car and let you get the set up perfect to match your driving style.

If you have slightly softer springs on the front the nose of the car will grip in corners and you will have more oversteer (back gets lighter and tends to go wide in corners). If the soft springs are on the back you will get understeer, which is how most production cars are set up nowadays because the inexperienced driver reacts better to understeer than oversteer.

Bushes (bushings)
These connect the suspension components to the chassis of the car. The rubber ones deteriorate in time.

New polyurethane bushes last longer and keep the handling much tighter but because they are harder they can make the ride a little more bumpy.

A set of new poly bushes will sharpen up the handling of your car reducing the slop and sway associated with rubber ones.

You can get a full set of suspension bushes for most cars although rarer models often only have the main bushes available in polyeurothane. Custom bushes can often be made up to suit your application.

http://www.torquecars.com/tuning/suspension-settings.php

Engine oil and the importance of good lubrication. (Oil Type, how much)

2009-11-02T19:00:00.000-08:00

When starting a cold engine let it tick over for a few moments to circulate the oil - most engine wear occurs within the first minutes of switching it on

Oil is an often overlooked part of the engine but more internal friction = lower power and more heat produced.

So the aim is to reduce the internal friction and cool the engine with a good oil and changing the oil frequently is vital to add longevity to your engine - certainly for the paranoid before and after a track day session and every 3-6 months.

This is not intended to be a highly technical guide that bangs on about SAE's Viscosity index and shearing of oil (if you want that ask for it in the feedback box below!).

This is a rough beginners guide to the slippy stuff and enables you to make an informed decision when choosing the correct grade and type of oil for your car.
When starting a car allow the engine to tick over for 10 seconds before driving it. Don't EVER leave a car idling though!
Which oil Viscosity should you use?:

Multi grade oils are popular and are rated typically with 2 numbers ie: 15w40 which shows

1) the thinness (viscosity or how runny it is!) at low temperature (W=Winter)

2) the thickness (viscosity or how sticky it is!) at high temperature (20w50 is thicker and 10w30 is thinner).

If the numbers are close together then the operating range and performance is more uniform. The second number is the important one unless you live in subzero climes! Use the recommended oil for you car - older cars sometimes prefer a slightly thicker oil to avoid leaks and burning in the cylinder but consult your workshop manual for your car.

Choosing oil that is too thin can cause permanent leaks in the seals. Running low on oil will typically wear the top of the engine and this wear is typified by a rattle in the top of the engine on acceleration especially when cold, the pistons will also wear more quickly and you will start to burn oil (well, your car will) producing a blue exhaust discharge.

Do not use a different grade to the recommend one unless the engine is very worn (in which case go thicker) or if the engine has been rebuilt (a thinner oil may be needed but the engine rebuilder will recommend the correct grade.)

Never put a semi or mineral oil in a car that requires fully synthetic unless this is an absolute emergency and get the oil drained and corrected as soon as possible afterwards. Try also to avoid mixing viscosity grades of oil and certainly never mix oil types.

NB: The oil light comes on to tell you your oil is empty and NOT when it needs topping up check your dip stick every 2 weeks or after a long journey - oil is CONSUMED by engines (but different cars have different consumption 16 valves seem to use more than their 8 valve counterparts) and always goes down - never up!

Some people recommend a thinner oil in the winter and a thicker one in the summer - your manual should have the recommended oil specs to air temperature chart. Sadly so many people just buy the cheapest oil they can get and use the Grade for the cars life summer and winter.

Which oil type - synthetic, semi synthetic or mineral?

A raging argument ensues about synthetic oil lasting for 36,000 miles or more. There is certainly some big advantages to synthetic oils but I would still recommend a regular filter change - the filter gets the tiny particles of metal from inside the engine that acts like a sandblaster inside your engine so even if the oil does last it will pick up lots of gunk from the engine.

While your changing the filter you may just as well change the oil anyway! Choose a good quality filter that collects the damaging small particles of metal. There are magnets available that wrap around the filter to collect more fine metal particles and these have be proven to be effective.
Engine oil Additives:

Most oils contain ingredients to resist combustion (stops engine fires!), detergents - cleans the inside of engines and anti cake agents to prevent the oil clogging up and blocking important bits of the engine. Some oils contain electrostatically charged particles (GTX magnatec, electrosynthtec etc) which bond low friction molecules to stressed metal surfaced, (crank journals, bores, cams etc) and help reduce cold engine wear.

There are additives that you can add yourself to the oil:
PolyTetraFlouroEthelyne - PTFE bonds to the surface of the metal parts to theoretically create a low friction surface. Other additives work in this way also and usually need the engine to be warmed up for the bonding to take place - most engine oils set out to do the same thing so the question of these additives has been raised.

(I have used X1 super lube and can vouch for it's effectiveness - it reduced cold start noise the engine ran cooler and I get slightly better fuel economy.) When you strip down an engine treated in this way the cylinders will generally have a hard black - almost mirrored finish - perfectly smooth. If you have a rattle from the top of the engine, sticking valves (especially if the cars servicing has been neglected) or cold start problems you may wish to give these additives a go - there is a chance the problem will not get any worse if you are lucky (avoiding an engine strip down).

Other substances condition the oil and make it 'sticky' (it works well and I don't know how!). The oil seems to cling to the surfaces of your engine for longer but it still lubricates and flows around and can even prevent minor oil leaks and reduce blowback and burning oil (Morays is the products name but I'm sure there's others around) The downside is that this additive is flushed out with the oil and needs to be reintroduced.

When starting a cold engine Torquecars recommend that you let it tick over for a few moments (don't run it for minutes though) to circulate the oil - most engine wear occurs within the first minutes of switching it on although there is little if anything that can be done about this - as the oil warms an thins it gives better protection (most cold start engine wear occurs due to acids created in the combustion process rather than friction). Only drive at 1/2 to 1/4 of your redline until the engine warms up unless you want to wreck the engine.

Some pistons, normally high performance ones are tapered which stops slap on the skirt which can be catastrophic to a piston. An engine specialist showed me scratch marks on a piston (on the tapered end) and explained that it indicated that the car had been driven very hard before it had warmed up - obviously pistons change shape slightly (expanding) as they warm up and this design prevents piston slap.

The piston contains less metal than the bore surrounding it, which may even be made from a different material with a different modulus of expansivity, thus the piston is likely to expand at a higher rate than the bores. Until the whole engine is warm and the bore and piston have expanded equally engine revs should be kept relatively low.

Important note to turbo car owners:
Turbo's spin at phenomenal speeds and are more prone to wear if the wrong oil is selected. They also run at high temperatures and this can show up weaknesses in the oils formulation. Also if you have a turbo you must wait for the turbo's turbine to slow down before switching off the engine.

The supply of fresh oil stops when the engine stops and the turbo's spinning will continue and wear it out (consult your manual for details or buy a turbo timer which keeps the engine running for you automatically shutting it off when it's safe to do so.) Most turbo manufacturers recommend the use of a fully synthetic oil.
How much oil should you put in?

Obvious Tip: keep the oil level below the max and above the min line !! - too much oil and it will get into places it shouldn't and could start seals leaking or cause other damage the engine ie:- burning oil/broken seals/piston rings.

Too little oil will cause premature wear. Always change the filter with the oil. Of the 7 oil changes I had done at garages only 2 had the correct level of oil - (3 would have caused serious damage to the engine if I hadn't spotted it (when I drained it out there was a whole litre too much oil!) after a service check the dipstick and complain if the oil is under the min or over the max mark!

I heard recently about a Porsche which was burning oil - it had been overfilled. When the correct level was restored the car thankfully didn't burn oil and no damage was done. The dipstick (on this car) should have been checked with the engine running as oil seeps into the pistons when stationary!

Don't assume you know how to check the oil. Consult the manual. If the manual says 4.5l then put 4.5l in and check the level in the way specified in the manual, allowing sufficient time for the oil to reach the sump, then top up if necessary - generally oil is checked with the engine warm but having stood for a couple of minutes to allow the oil to settle. Although I have slagged off garages the average motorist is equally negligent with 1 in 4 having below the minimum oil level in the engine.

Please also note that only car engine oils should be used, not motorcycle oils, which are designed for a totally different purpose (they have to lubricate the gear box and also most bike clutches run in oil) - the same goes from transmission fluid.

http://www.torquecars.com/articles/engine-oil.php

Cold air intakes and induction kits and the effect on performance. Tuning Car

2009-11-02T18:56:00.000-08:00

Improving the Suck – if you put a piece of cloth over your mouth and suck in air you will not have too much of a problem but if the cloth were wet or a double thickness things start to get harder. Your engine, just like you, needs to breath air.

The air filter is a very necessary part of the engine unless you are operating in a laboratory so the aim is to get an efficient air filter that is not too thick and is not oily, greasy or dirty. This is where induction kits and sports panel air filters come in.

TorqueCars have looked at the various types of filter materials available today and we have concluded that the best filters for flow rates use oiled cotton gauze as their filtration medium.

These are not particularly easy to come by for most applications, so for the average fast road car we would recommend going with one constructed from sponge impregnated with a dirt retentive spray.

This slight coating of oil will aid filtration. As an alternative to sponge get a filter which comprises layers of a fine grade metallic mesh as both of these will flow better than the standard paper filter.

The oil sprays for air filters have been traced to problems with the mass air flow sensor. We must stress that you should only use a light coating of oil on the air intake side of the filter. It is a good idea to clean the mass air flow sensor periodically anyway.

The bigger the surface area of the filter the better the air flow will be. Mainstream cars today can be fitted with an air induction kit which completely replaces the air intake box.
Cold air induction kits, a cheap way of making the most of induction roar

The plus is much better air flow, particularly at higher revs, and the induction roar as air is sucked into the engine the downside is also the roar - some people dislike the extra noise these kits create .

Smaller engined cars can actually lose power when an induction kit instead of an airfilter is fitted. It can be challenging to deliver COLD air (which carries more oxygen) to the engine as the temperature under the bonnet can get quite high and and a 20 degrees rise in temperature can rob you of up to 3% of your power!

Under bonnet temperatures can quickly rise to double this. An intercooler can be added which is sprayed with Co2 and reduces the temperature of the air intake. It should be noted that in some small engine non turbo applications the car will feel less powerful with an induction kit - in these instances the best option is a direct replacement panel air filter which goes in the standard airbox.

Sucking warm air in from the engine is a great way to lose power.

Make sure you have a cold air feed pipe to get cool air from outside of the engine bay - cold air carries more oxygen.

So the best air induction kits come with a cold air feed pipe and are fitted in an air box which shields the intake air from the high under bonnet temperatures – the best compromise between the standard air intake box and the induction kit. Some kits have a long pipe which the filter sits at the end nearest the bonnet which really does help cut down the noise and improves the intake temperature.

Induction kits that protrude under the front bumper which claim to get more air forced in through the pressure built up on the front of the car as it cuts through air do not have significant power gains, other than the benefit of the cold air from outside the engine bay, - the RAM effect takes speeds up over 100 mph before a benefit is realised - they are however a great way to collect many botanical specimens of fly's, moths and bugs in the air filter!

NB: Be careful where you site the cold air feed - the last thing you want is to be sucking water into the engine every time you splash through a puddle.

If the induction kits air filter is enclosed in a box with a cold air feed, then more power can be obtained avoiding the hot under bonnet air (Carbon fibre boxes are very good for their heat shielding and durability). It also good to wrap a the exhaust manifold with a heat resistant material to keep the under bonnet temperatures down and tasteful vents can be added to the bonnet to take away the heat.

Induction kits sometimes come with a guarantee of "more power". In reality though, the power gains are so small, on small engined cars, they would not be noticeable in real life. Secondly the power increase tends to be at the higher end of the rev range and your low down power band will suffer.

So to summarise, if you have a large engined car (or an engine with good low to mid range torque) fit an induction kit with a cold air feed. If you have a small engined car or one with little power in the lower rev band fit a direct replacement sports panel air filter.

http://www.torquecars.com/tuning/induction-kits.php

Spark plugs

2009-11-02T18:53:00.000-08:00

One of the most essential elements in an engine is the spark plug which is often overlooked.

The stronger and larger the spark the better the combustion.

A bigger spark will ignite the air/fuel charge more effectively.

It is the burn rate and expansion of the flame front which causes the piston to change direction and produces the Power stroke.

Peak power is achieved when the flame front is at the point of maximum expansion. It is therefore essential that this happens at the same point each time and in each cylinder. The spark initiates this burn so a good strong consistant spark does a lot to give a consistant burn.
Performance spark plug selection should not be overlooked. The spark is an essential part of the combustion process.

Spark plugs are heat rated. Running with a plug that is too hot can cause premature ignition which can cause damage to your engine.

Spark plug technology has come a long way since the early days, new materials are in use which have lower resistance and longer life cycles. A set of modern Iridium plugs will typically last for 40,000 miles and will not require regapping or deglazing in its life cycle.

Copper tipped spark plugs actually benefit from a deglazing which can be done with some emmery paper, sanding paper or a wire brush. This will maintain the economy and efficiency of the engine as the glazing inhibits the spark consistancy and strength.
Dual core spark plug

There are a number of different electrode types. The overall aim is to get the biggest spark. We are talking fat as well as long. A good spark causes a much better burn. We have split tip electrodes, double and triple electrodes.

For most drivers though you will not notice a difference between these and a good set of standard plugs with a copper core. You will only get one spark no matter how many electrodes you have although a multi electrode plug may last longer.
Fitting spark plugs.

Fitting plugs to a car is a simple job which even the most mechanically inept can perform. Ensure you have the correct tool. Locate the 4 leads going into the center of the engine.

You may need to remove an engine cover or covers which are usually made of plastic and lightly screwed or clipped on (most cars we see have 4 cylinders in line but there are many other engine configurations around, 5 cylinder engines will have 5 leads and a V6 will have 2 banks of 3 but the idea is the same with one lead for each plug at the top of each cylinder.)
Spark plug internal

A cross section of an engine showing the spark plug cross section (white) to the left of the image.

We recommend doing these one at a time to avoid getting the leads mixed up.

The leads and plugs follow a set firing order and if the leads are put in the wrong plugs you could damage your engine.

Working from left to right take out the first plug using the removal tool. A plug will tell you a lot about the condition of your engine. Place them in order of removal for later inspection.

The most important point of putting the new plug in is to get it straight. Fit the plug only finger tight. In some engines you will be able to reach the plug tip easily with your fingers, in other engines you will need to use the tool to get a reach - if this applies to you just hold the tool like a pencil and do not use any leverage at first.

Whichever method you use please ensure that you only fit it finger tight initially. When it is as tight as you can get with your fingers pull another quarter turn on it using the plug tool.

The engine block is softer than the plugs so any damage from cross threading them is going to occur on the engine. (If this does happen a heli coil or re cutting the thread will usually fix the cross threaded hole.)

Next move on to the next plug and repeat. When you have replaced the plugs look at each of the old plugs. They should all be the same colour indicating a balance in the engine firing and fuelling.

A healthy plug has a dark grey soot on it.

A light grey or white soot indicates that the engine is running too rich.

Black soot indicates that it is running too rich.

Oily or greasy plugs can indicate major engine wear and you should investigate this more fully.

Cracks on the plug can indicate problems with excessive heat and should be investigated especially if present on 2 or more plugs.

http://www.torquecars.com/articles/spark-plugs.php