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Frequently Asked Questions - Engine
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| 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.
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| 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!
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| 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.
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| 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. |
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