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Peugeot 8v Engine
Frequently Asked Questions - Engine

Induction Kits and Filters
Q. What does an induction kit do?
A. An induction kits improves the airflow into your engine. The primary aim of any performance modification is to get more fuel and air into your engine. The induction kit does this by providing a more direct route for the air, into the inlet manifold. Also, a high quality cotton gauze filter allows more air through. Usually this is from a better position at the front of the car to take advantage of the cooler, denser airflow.

Q. Do induction kits give more power?
A. Yes, induction kits do work. They are particularly good when combined with other modifications such as a high performance exhaust or gas flowed head and cam. Don't expect miracles when fitted on their own, but you will see more power.

Q. Are there any other benefits in fitting an induction kit, besides more power?
A. Yes, the kit removes the need for the standard air box and pipework, giving a neater underbonnet look. It also makes servicing and maintenance easier, as there is less in the way. Also, the cotton gauze filters such as Green and K&N are cleanable for an indefinite life.

Q. Will there be any problems if I fit an induction kit?
A. No, but you need to be aware that the engine will be noisier under acceleration. This is because the manufacturers installation is removed and much of this is designed to reduce noise and resonance. However, you will have the benefit of a much sportier induction sound - ideal for the car enthusiast.

Q. Can I fit an induction kit myself?
A. Yes, induction kits are easy to fit and always come with full instructions.

Q. If I don't want to remove the manufacturers system, are there any alternatives?
A. Yes, you can fit a high performance replacement filter. These improve air flow through their better quality cotton gauze construction.

Q. Why don't I just run without an air filter for maximum power?
A. Never be tempted to run without filters. Your engine will suck in dust and dirt particles which will wear away the mechanical components very quickly. That's if you are lucky enough not to suck in a stone which will cause immediate engine failure. Good quality filters do not significantly reduce airflow so there is no excuse for not running an air filter - even on a race car.

Engine Conversions
Q. I have seen the 205 with an Mi16 engine installed. What is involved?
A. This conversion can be completed by any competent mechanic. There are several main areas to consider:

1. The base car - start with a GTi model as this has the easiest specification to work with. If you start with a non-GTi model you will have a non-injection wiring loom, inadequate front suspension (the design is different and you will need to swap to a GTi sub-frame assembly to change this) and narrow wheel arches. You will also have fewer engine ancillaries that can be re-used. The GTi suspension and braking capabilities are easily able to cope with the 16v power.
2. The donor 16v engine - make sure you buy an engine with all the ancillaries, plumbing, wiring, ECU and other control components you need. These are costly to source separately. Your requirements will depend on how you intend to run the engine (see below). Unless you know the engine history, it is worth at least fitting a new set of valve stem seals, head gasket and cam belt. Also fit a new clutch while the gearbox is off.
3. Fitting the engine - drop the old engine out under the car. Mate the 16v to the 205 gearbox. Use a 1600 gearbox for lower ratios, 1900 for higher top speed and more relaxed motorway work. Note that the 1600 has different driveshafts and hubs to the 1900, so swapping gearboxes means swapping these as well. Lift the 16v up into the engine bay. The engine mounts are the same.
4. The exhaust manifold - the Mi16 exhaust manifold hits the 205 bulkhead. You can cut and fold back the bulkhead lip and re-shape the bulkhead behind the manifold to relieve this. You can also shorten the bottom engine mount, but consider this a temporary fix as it can cause oil starvation problems under heavy cornering. For the best job and better power, buy a bespoke manifold or have one made up.
5. The radiator - you will need to make up some brackets to drop the radiator away from the 16v inlet manifold, if you run the engine on its standard injection. If you run sidedraught carbs, there is no need to do this. You can buy (or make) a shorter 16v inlet manifold to save moving the radiator - the choice is yours and based on economics.
6. The plumbing - you will need to use a combination of 205 and Mi16 coolant hoses to connect everything up, including the Mi16 water cooled oil cooler (you could use the 205 1900 air cooled oil cooler) and 205 header tank.
7. The wiring - there are two ways to approach this. Firstly, you can retain the 205 engine loom but you will need a distributor conversion plate to use the 205 distributor. There are several disadvantages with this: you have to buy a conversion plate; you are running with the 8v ECU and therefore the 8v fueling and ignition settings and you have to have the rev limiter disabled in the 8v ECU as it cuts in before maximum power from the 16v engine! My preferred method is to use the 16v engine loom and Motronic 4.1 ECU. This requires an amount of wiring in, but you end up with a very professional conversion, using all the original Mi16 ancillaries and control systems.
8. Enjoy harassing innocent drivers of more exotic machinery!

Chips and ECU Modifications
Q. How does a chip change work?
A. Your cars engine is controlled by electronics. The electronic control unit (ECU) takes signals from the engine through sensors, then decides what ignition advance and fueling to provide, depending on load (throttle) speed (rpm) and various other parameters such as temperature.
The manufacturer will have spent millions developing the car, ECU included and you can bet that it is pretty well sorted as standard. However, it will be set up for a compromise between performance and economy. By swapping the chip for one with different parameters ie. more fuel and different ignition advance, the idea is that you can gain some performance.

Q. Does chipping my car actually work?
A. The short answer to this is not usually. Normally the manufacturer has things pretty well sorted from the start. There are some exceptions, such as the Mi16 which runs a bit lean in the mid-range as standard. This was for better fuel economy for the fleet market. You can remove some flat spots with a 'SuperChip', but don't expect miracles! You will get better value for money and better results by modifying the traditional way: induction kit and exhaust; gas flowed head and cam. In addition, spend the money first on making sure your engine components are in good condition: plugs, leads, distributor cap and arm etc.

Q. I have heard of the 'UniChip'. Is this the same as chipping?
A. No, don't confuse this with chipping. The UniChip sits piggy back on your existing ECU and can be fully programmed by a rolling road operator. It is ideal when you have had some modifications to your engine, which go beyond the capabilities of your existing ECU. The UniChip can be programmed to provide exactly the fueling and ignition advance that your new modifications need - with superb results.

Engine - General
Q. I have a '98 1.9 Turbo Diesel Pug 306 which has developed a new whistle. The problem is most apparent when the engine is idling, although it does exist when on the move as well, and increases in frequency as speed/revs increase. The noise is not there all the time, and will occasionally disappear, although it does seem fairly persistent now. My local Pug garage are at a loss.
A. This could be many things, from a noisy alternator bearing to a leak in the induction system. In this case, it turned out to be a noisy water pump.

Q. My engine runs very badly on tickover. What causes this?
A. There are many causes of a lumpy tickover and it is a case of running through the most likely in a methodical way until the problem is cured:
1. Ensure that all of your ignition components are in good condition: spark plugs; distributor cap; HT leads etc.
2. Check the breather system hoses for leaks or blockages. Check the dip stick seal is a tight fit in the tube. Check the seal on the oil filler cap.
3. Check the idle correction and mixture (or have a garage check this for you).
4. If the problem still persists, you will need to have the ignition/electronic control units checked by a garage.

Q. My 405 1905cc petrol engine smokes badly from the exhaust (black smoke), especially when cold. What is likely to be the cause of this?
A. The most common cause of smoke from this engine (and also 1600cc as fitted to 205 GTi, 309 among others) is worn valve stem oil seals. These stop oil from the cylinder head passing down the valve guides and into the combustion chamber. When they wear and/or perish, oil can pass them and is then burned with the combustion mixture, causing black smoke. The seals are only about 80p each, but the job entails removing the cylinder head for a rebuild.