A Reliable starts with Good Maintenance

Hi there fellow Uno Admirers

Before you can modify any car it should be in good working order, otherwise you will end up chasing your own tail trying to resolve problems as they occur. Quite a few times I have been asked to modify an Uno only to find that when I opened the Bonnet it looked like the Exxon Valdez supertanker had run aground in the engine bay, I would then tell the owner until he could be bothered to steam clean the engine I would not touch his car.

* So my first suggestion is buy a can of „Hyperclean“ by „Coma“, this engine degreaser is better than most because it contains an anticorrosion agent. I think there is nothing worse than having to do some work on your own car and end up covered in grease/oil or shit up to your elbows, there is the added benefit that any oil leaks the engine may have will become evident.
* One of the most common reasons for oil all over the engine on the Uno is the rubber on the dipstick, this with age wears and becomes hard, end result is oil leaks out, this rubber is available separately and the cost is ridiculous, the other is oil leaking from the cam carrier gasket.
* I you are going to do any work on your Uno buy a workshop manual, besides guiding you on how to do things, it also has all the specifications of the Car, like valve clearances, Tightening torque figures for loads of bits, etc, probably the best ten pounds you could spend on your car.
* Use quality parts, don’t skimp on bits like spark plugs or engine oil, always use synthetic engine oil, and replace at the recommended intervals i.e.: 6000 miles or 10,000 km. As for spark plugs the best ones I have found are the NGK triple electrodes BCPR 7ET for both the 1.3 and 1.4 engine. Check the rotor arm and distributor these items also wear out, replace at least every 50.000 miles, Don’t buy cheap HT leads, stick to either the original Fiat ones or Use Magnecor Race leads,
* Check the valve clearances on your engine at least every 12.000 miles, although the camshaft and the buckets with their shims run in a bath of oil and suffer very little wear, but valve seats do wear, and if they are not set correctly the engine will not run smoothly especially at idle. The clearances (cold) inlet: 0.30-0.35mm and exhaust (Cold) 0.40-0.45mm. Once adjusted they normally stay within tolerances for aprox 30,000 miles. But because of this many garages and owners neglect to check or adjust them.
* Check the tightness of the nuts that hold in place in the inlet and exhaust manifolds, for some strange reason the nuts at the cambelt end of the engine tend to work loose, and air leaks as a result can occur, which lead to rough running, loss of performance and strange air leaking noises. Also check the hoses on the engine for the induction system, check their condition and proper fitment, otherwise they could blow under boost and then the engine will not run, not a nice job refitting an intercooler hose on the side of the road with a burning hot engine.
* Check that you are getting full throttle, to do this properly remove the Hose that goes to the inlet manifold, get a friend to put their foot flat on the floor with accelerator, quite a few of you will find that the butterfly doesn’t open fully or goes beyond its maximum opening and starts to close again, in almost most cases you will find that the throttle stop is not adjusted correctly. If you lack throttle travel (i.e. it doesn’t open fully) adjust the cable that goes from the throttle butterfly to the linkage, invariably the always some in the cable, take care not adjust to tightly, otherwise the throttle position switch wont click when you let go of the throttle, if that still doesn’t give enough throttle travel, then you have to grab the throttle pedal and pull it upwards gently to bend it (don’t go mad here!!). If it opens too far, loosen off the adjustment on the throttle cable, once its set correctly adjust the throttle stop screw.
* Change the antifreeze and coolant every 2 years, antifreeze in a modern engine carries out 2 functions: 1) prevents the coolant from freezing inside and if mixed at the recommended ratio of 50% coolant and 50% antifreeze it will protect your engine down to –35ş degrees Celsius. 2) The antifreeze prevents corrosion inside the engine, and these agents loose their effectiveness with time. In order to minimise deposits inside the engine and cooling systems its a good idea to add a flushing agent to the cooling system before draining in most cases they must be present for aprox. 24 hours to loosen sludge and other deposits and when you refill the cooling system use distilled water instead of tap water to minimise a build up of deposits and sludge.
* Change brake fluid every 2 years at least, Not everyone realises this but brake fluid is Hygroscopic, which means that he fluid absorbs moisture, and what could happen is that the brake fluid will exceed 100ÅŸ degrees Celsius under hard use and the water present in brake fluid will boil and turn to steam, in the best case this will give a spongy brake pedal, in the worst case the brake pedal will go the floor and the car wont brake because although a fluid is not compressible, a gas is (such as steam!!). When you replace your brake fluid should use a minimum of D.O.T 4, nowadays mineral based Brake fluid of D.O.T 5 are becoming available, which are even better because they have a higher boiling point.
* For those of you who are real road warriors, a cheap mod that is worth doing to the brakes is to remove the shields behind the brake discs, In my own car equipped with standard brakes apart from fast road performance pads, I could not do more than 2 laps before severe brake fade crept in, when I removed the shields I could do more than 5 laps before brake fade became apparent. Don’t use cheap brake pads as problems with brake fade and squealing could be a problem them, My preferred make for pads is Ferodo, a word of warning, I don’t recommend other than standard pads for the rear brakes, whichever the pad manufacturer is, because if you fit fast road pads to the rear, and you have been out for a hard drive, pull up outside your house, apply the handbrake, the handbrake will not hold the car on an incline once the brakes cool down.
* Another mod worth doing is to remove the cooling fan for injection system and its associated pipework as I never known one to come on, so as Colin Chapman used to say „never give a washer a free ride „. So why carry around the extra weight. It also helps unclutter the engine bay. Also worth doing is to remove the original air filter housing and crosspipe that goes above the radiator and fit a direct induction filter, the cost doesn’t vary much from that of a performance replacement of the standard air filter element, again this removes weight and uncluters the engine bay.

All these little details help your car deliver the best performance, whilst remaining reliable and are a good base to start modifying things further.

Good luck every one

Driven by Passion
Joe Rubido

Written by Joe Rubido 15/07/98
E-mail jrturbo@activanet.es

Tekst na engleskom koji se bavi modifikacijama Una Turba. Dok sam vozio ovaj automobil ovaj tekst mi je bio koristan pa ga ću ga podeliti sa onima koje ta tema zanima. Tekst je preuzet sa (sada neaktivnog) sajta www.unoturbo.co.za

UNO TURBO; BASIC ENGINE BOOST UPGRADE

Hi there everyone.

As promised long ago, I have got round to writing an article on how to modify your Uno Turbo. In order to keep things simple, cost effective and reliable this article will show an uno engine a modified air filter arrangement, and how to raise the boost.

Above you can see the picture of a standard uno engine bay; you will have to remove the following items to gain access to the turbo actuator hose:

The intake hose to the airflow meter
The hose from the airflow from the airflow meter to the turbo intake
The joining hose and metal pipe from the turbo to the intercooler
The bypass or recirculation valve (same as a dump valve)
The airflow meter itself
Disconnect the wires to the maximum pressure sensor
The injector cooling fan and its associated trunking
Once these items have been removed the turbo actuator and the short rubber hose will be visible and accessible.

Above you on the left you can see a photograph of the turbo actuator and the hose, on the photo you can see hoseclip being loosened in order to remove the turbo intake hose from the airflow meter, you will need to do this in order to have enough space to work.

Also above on the right you can see a picture of the bypass valve, this item is a dump valve that releases the excess boost pressure when close the throttle back to inlet of the turbocharger, instead of releasing the excess charge to the atmosphere like the aftermarket dump valves you can buy, On the Uno Turbo there is no need to fit an aftermarket dump valve because as you can see Fiat had the good sense to fit one as standard unlike Renault on 5 GT turbo or Ford on the Escort and Fiesta RS Turbo.

You should replace the original short hose with a longer hose, long enough to fit a bleed valve in position that at later moment can be adjusted, so the length of the hose installed should be aprox. 1 meter length. you can fit a shorter one but access to the bleed valve will be more difficult.

Once the bleed valve has been fitted, refit all the hoses in the reverse order, taking care to make sure that that they are securely fitted. To begin with the bleed valve should closed, also those who haven’t removed the injector cooling fan, and the shroud under the plenum chamber should take the opportunity to do so now, as this never comes on and is about as useful as an ashtray on a motorbike, as Collin Chapman used to say „Never give a washer a free ride“, after you have removed these items the engine will considerably less cluttered.

When it comes to refitting the wires to the maximum boost pressure switch don’t, just insulate the terminals with tape so they touch each other and secure with a tie rap somewhere.

Also at this stage whilst refitting things, its a good idea to fit a direct induction airfilter and remove the airfilter box and the pipe that goes across and above the radiator, again this will help unclutter the engine bay and make future servicing and repairs easier.

Recommended things to do at this stage is to replace the spark plugs with triple electrode one from NGK, model BCP7 ET, check the condition of the distributor cap and rotor arm and replace if they show signs of excessive wear.

Once everything has been refitted, your car should start as it would normally, take the car for a short test drive to ensure everything is order, it shouldn’t feel much different at this stage except that you will have a bit more induction engine noise. If everything is ok, we move on the next step, which involves adjusting the boost by opening up the bleed valve. Under normal circumstances a standard Uno turbo will never exceed 0.5 bar boost on the gauge, open the bleed a fraction and take the car for a test drive, pick a quiet road because your attention should centered on what boost the engine runs.

You aim to achieve 1.0 bar boost and no more! which the engine will achieve in 4th or 5th gear at aprox 3500 rpm under full throttle, above that the boost will start to drop, this is normal with the 1300 Uno turbo, because the standard turbo isn’t big enough to deliver high boost at high engine rpm, you will probably find that the boost level at 6000 rpm drops down to 0.75 bar. However tempting it is to raise the boost further do not do so, as the fuel injection system in standard form can not cope with more boost, and your engine will run lean with serious risk of damage. You have been warned !!

With these modifications if your engine is in good order it will develop approximately 125bhp, a little bit more if you fit a performance exhaust system. These are real horsepower figures and not the bullshit and exaggerated claims you will come across in many magazines adverts.

It also very wise, to take the car to a rolling road to confirm that engine is not running too lean at full power and at the same time the will tell you how much power you engine develops.

I should also warn you that this modification also increases the torque output of the engine, and if your clutch is worn and on its last legs, by raising the boost it is quite possible that it will slip, if this is the case reduce boost pressure until it stops slipping and organise Having a replacement fitted.

The author is not responsible for any damage that may occur as a result of carrying out these modifications, the owners do so at their own risk! I have modified quite a few Unos as described in this article without a problem but as I cant personally check the modifications that each of you carry out, I cant be held responsible.

4/12/98

e-mail Joe at jrturbo@activanet.es

Tekst na engleskom koji se bavi modifikacijama Una Turba. Dok sam vozio ovaj automobil ovaj tekst mi je bio koristan pa ga ću ga podeliti sa onima koje ta tema zanima.

Uno Turbo Modifications.

Introduction:

Before one can contemplate modifications to this engine you need to fully understand how a turbo-charged engine works.

The Air Engine.

Any piston driven engine is basically an air pump. In a conventional (non-turbocharged engine) the job of filling the cylinders in done by the pistons. On the inlet stroke the falling piston produce a partial vacuum in the inlet manifold and the fuel-air mixture is „sucked“ into the cylinder. On the compression stroke the fuel-air mixture is compressed and ignited by the spark plug so producing the energy to drive the piston down-wards. On the final stroke the pistons expel the burnt gases out of the cylinder into the exhaust system.

The Turbocharged engine.

The turbocharged engine is radically different to the conventional type, not so much in the mechanical parts, but in how the inlet fuel-air mixture (the charge) is ingested.

In a turbocharged engine the inlet manifold does not operate at a partial vacuum but is positively pressurised by the output from the turbo. You need to appreciate that most turbocharged engines use a comparitively low compression ratio. In high performance engines compression ratios of 14:1 or higher are used for a very good reason. Firstly by using a high compression ratio the vacuum produced in the inlet manifold is greater and a larger volume of charge is ingested into the cylinder. On the compression stroke the mixture is compressed to a pressure which is x number of times over the atmospheric pressure. (The compression ratio is simply the swept volume of the cylinder divided by the combustion chamber volume) For a turbocharge engine the swept volume is fixed, as in the conventional engine (non-aspirated) and so is the combustion chamber. But as the manifold pressure is now positive relative to the cylinder, more charge is ingested. In an example using the case where the compression ratio is say 7:1 and the boost from the turbocharger is 1 atmosphere (1 bar) the effective compression ratio is 2x the actual or 14:1. Power output is directly proportional to the size of the combustion „bangs“ and the revolutions per minute of the engine. For high output powers a combination of high boost and high rpm will give high output power. (Duckworths formula!)

If you have read this far and fully understood the above you are now in the position to understand the final part. If you didn’t understand the above – go back and read it again. Only when you fully understand the principles can you see how adjusting the boost pressure can give added horsepower.

Increasing the boost.

For a given amount of boost and a static compression ratio, for a particular type of fuel, there is a certain maximum output power that can be obtained.

By increasing the boost, assuming that no bad side affects occur, then the power output is directly proportional to the boost. By bad side affects I mean premature ignition (knocking or „pinking“) or failure of the rotating parts, eg a connecting rod

failure causing severe engine damage. All of these are possible in a highly stressed engine. The Uno Turbo is generally a very good mechanical model, but all items have their limit.

The Down-side of turbocharging.

In the conventional engine (non-turbocharged) the trick to getting the maximum horsepower is to keep the inlet charge as cold as possible. If this can be achieved the charge will be dense and will allow the maximum power to be extracted from the fuel-air mixture. Unfortunately with the advent of turbocharging, which incidentally came about during World War 2, the air passes through the turbocharger housing and due to the combined effect of compression and the proximity of the exhaust impeller housing is heated to a temperature well above the ambient. The inter-cooler job is to reduce temperature of the air to something around ambient. This will depend on several factors. Firstly the ambient temperature. Secondly the surface area of the intercooler should be as large as feasible. Thirdly the internal volume of the intercooler should be small. All of these are variables and often, as in most engineering problems, a compomise has to be made. A large surface area for the intercooler often means the internal volume is not as small as one would like. The penalty of this is that the turbocharger has to fill the internal volume with a lot of air before the boost pressure comes up, the so called „turbo lag“.

Turb lag is a fact of life and there is little one can do except adapt ones style of driving to the limiting factors. Having been used to driving a turbocharged vehicle if one now steps into a normal vehicle the driver has to readapt to prevent wheel spin on take off.

Increasing the density of the inlet charge.

For a particular atmospheric pressure and temperature there is a definite amount of fuel-air mixture which can be maintained without the fuel falling out of suspension and becoming droplets of petrol. A very good way to both increase the density and lower the charge temperature is to add water to the inlet mixture. Water is very low cost and has several plus factors. Firstly it is very easy to add water under pressure to the inlet side of the turbo by using a metered spraybar in the input to the turbo. Water has the low specific heat required to both cool the mixture and impart added power. When water is ingested into a conventional engine the water is turned into superheated steam under combustion and provides and extra „kick“ to the piston. This can be as much as 30% if correctly engineered. In reality 20% is more likely as the water is not always vaporised effectively, but in a turbocharged engine we have the turbine blade in the inlet to give us an added benefit. The water if injected into the inlet side of the turbocharger is firstly atomised by the rapidly spinning blade and takes up the heat from the combination of the compresing of the air and the excess heat from the exhaust impeller side of the turbo. In all the turbo is made for water injection and 20 to 40% extra power can be achieved by setting the water flow at the correct level. A plus factor is that the engine runs smoother and higher ignition advance can be used to good advantage to develop even more power.

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Dangers involved with water/turbocharging.

All the above seems too good to be true and as with all physical items there are a few vital points to bear in mind. If the water feed is too vigorous the danger exists that too large a water droplet will strike the rapidly spinning turbine blade of the inlet impeller and cause severe damage. The inlet impeller is going at up to 200,000 rpm in the Uno Turbo. Even a minute drop of water is like a piece of concrete and if a piece of impeller blade is sheared off the resulting imbalance will immediately destroy the turbo. Therefore it is crucial to increase the water feed very slowly and carefully to get the optimum setting.

14/9/98

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Track: BlackWood GP Normal
Weather: No Wind
Car: XF GTI
Green Line= Optimum Racing Line
Km/h | MPH= Both

Turn 1—————————
After completing the first lap, you’ll be coming to Turn 1 at a higher speed around 100 MPH (160 Km/h). Brake point for this turn is at 80-75M slow down to about 44 MPH (70 Km/h) then gently come off brakes and apply half throttle as you are entering the apex. Apex speed is around 40-42 MPH (64-67 Km/h). As your exiting the turn apply more throttle.

Chicane—————————
Entering the chicane is very important, If you enter it incorrectly you will exit incorrectly. The trick to entering it is to use the curb in the first turn of the chicane. Try to get real close to the tyres.
Example Pic:

Look at the graph at the bottom to get an idea how to go through the chicane. Exit speed should be around 70-71 MPH (112-113 Km/h) Full throttle through the turn.

You know you’ve negotiated sector one properly when you getting times of 32.3x – 32.5x (or maybe even 32.6x). Another good indicator is that you will need to shift into 4th gear almost immediately after leaving chicane 1.

Turn 4—————————
(Turn after back straight): When approaching the turn, brake point will be around 105-100m. Then enter the apex at 55 MPH (88 Km/h) at half throttle, As exiting turn Full throttle.

Turn 5—————————
This turn is much like the first chicane, If you screw up the entry you will screw up the exit. Try to go as wide as you can (*Make sure none of your tyres touch the grass or you will slide*) As you are approaching the bridge and exiting it start to brake to about 57-60 MPH (91-94 Km/h) executing the turn at half throttle, as your coming to Turn 6 go full throttle (At full throttle point you should be somewhere along 60-63 MPH (96-101 Km/h))

Turn 7—————————
As your coming to the brake point 70-60M let your left side of the car (Only left side) touch the curb. Brake at the brake point 70-60M as your coming of the brakes apply about half throttle while entering the apex at 55-57 MPH (88-91 Km/h) as your exiting the turn go full throttle. You can either go around the cones or not.

Turn 8 and Turn 9 (final left/right)—————————
An ideal speed here is 60+MPH (62 is good). Brake, then aim at the cone that is farthest from you (the farthest to the left) while going 60+ MPH (96 Km/h). Ideally, as you take the right hander, you want to be going 64 MPH (102 Km/H) when you hit the curbing on the last right turn.

Guide Written By: Jonathan Asencios (JaBerXSpeed) And James Golz (Dolemite) Please don’t use this content without written permission.