Anyhow, back to the topic - Clio 172 standard exhausts are notoriously awful, be they on the Ph1 172, the Ph2 172 or on the 172 Cup. The systems are all almost identical – the Ph1 has a slightly shorter catylitic convertor, meaning that it is necessary to have a spacer if you wish to use a system designed for a ph2 172 or a Cup/Ragnotti, as the centre pipe may be a little short.

The systems are pretty dreadful, they rot reasonably quickly, and end up falling off in most cases either where the centre goes into the backbox, or the hanger pulling off the backbox. I have seen plenty of Catalysts failing as well.

The interesting thing is that most of the aftermarket systems aren’t much different in terms of quality – generally they are blooming awful. With baffles blowing, booming centre sections, and poor joins or welds. It is actually the reason that YozzaSport started doing clio 172 exhausts – because we didn’t want to put the poor products on the car when our supersprint system wore out and eventually fell to bits.

Road exhaust systems are always very difficult to advise people on, as the first question that people normally ask is “How loud is it?” Many times it is impossible to answer this accuarately, as it is such a personal thing. The other reason is that most systems that you will buy off the shelf will meet 98db requirements, as most trackdays are run to this kind of restriction, as are a lot of race events.

Removing the Catalytic Convertor on a Clio 172

One of the first points is the Catalytic convertor. If you remove the Cat on a standard 172 you will find that the noise will increase considerably. It is however the most cost effective modification that you can make to the car.

You will gain between 4-5 BHP normally with just a decat. We have tested both 2.25″ and 2.5″ pipes and find that 2.5″ decats are more effective in producing more power, however, the difference between these two diameters can be about 1db in terms of outputted noise.

Sports Catalytic Converter (Sports-Cat)

I would strongly advise against a sports cat – they are incredibly expensive for what you get and you may as well invest in a very high quality cat-back system rather than spending almost 75% of the cost of a cat-back system on a sports cat. Its a waste of time. If you don’t want to de-cat the car, just forget it, and leave the standard cat in – the power difference won’t be noticeable in most instances.

Lambda Sensors and Emission Warning Lights

On the Clio 172′s you can normally get away with simply removing the second lamda sensor, without the emission warning light coming on. Simply unplug the sensor and tie it up under the car – it is worthwhile putting the plug in a little protective bag and ziptieing it up under the car. If you plug the second lamda in without a catylitic converter in place the emissions light will come on within a matter of minutes.

The standard exhaust system part numbers are as follows:

172 Exhaust Manifold - 8200162399 – £440.68+VAT

182 Exhaust Manifold - 8200444565 – £440.69+VAT

172 Ph1 Catylitic Convertor - 6000073701 – £712.11+VAT

172 Ph2 Catylitic Convertor – 6000073732 – £821.49+VAT

172 Manifold to Catylitic Convertor Gasket - 6000073668 – £37.81+VAT

172 Centre Section Exhaust Moiunt - 7700424341 – £6.03+VAT

172 Ph1 Centre Section - 8200332139 – £148.21.VAT

172 Ph2 Centre Section - 8200332139 – £148.21+VAT

172 Backbox - 6000073740 – £103.38+VAT

172 Exhaust Mount - 7700424339 – £18.78+VAT

172 Exhaust Joining Sleeve - 8200661296 – £19.11+VAT

Clio 172 Race Exhaust Systems

How can I get the most power out of my Clio 172 Exhaust System?

Unfortunately one of the most popular systems to get the most power from a relatively standard car are no longer produced (since about 2003), you would have been looking at the 63.5mm(2.5″) SuperSprint system, if you were running throttle bodies (ITB’s) you would probably have considered their 70mm (2.75″) system, but unfortunately these systems were only produced in very low volumes for the European race series like the Dutch touring cars, Belgian Endurance racing and VLN where the clio cup race cars were very popular, as well as for rally cars over in Europe.

[Coming Soon]

So we would suggest that the two systems to consider if you are racing would be our Clio 172 Race Exhaust System, the Orbisound system or a cheaper alternative might be the OMP race system.

The Orbisound system is a race system and to be honest, you shouldn’t expect it to last that long as it is very lightweight. However it comes at such as cost and given the fact that it isn’t as robust as some of the other race systems out there on the market (OMP) it is an expensive option. If you are looking for the light weight system then the Orbisound system or the OMP race systems are probably the lightest out there as I said.

At a couple of kilos more, our YozzaSport system was designed to produce as much power as possible, but still retaining the long life and high quality that people should expect. We tested a number of different bore pipes – 2.25″ & 2.75″ and they basically made no difference to the output power nor torque, so we stuck with the middle ground to keep the systems within noise limits.

The perfect exhaust system on a 172 should be:

Stealth Exhausts

What is a stealth system? It is a system that is hidden behind the bumper – the same as the OEM exhaust. I.E. A replacement that doesn’t hang below or require cutting into the bumper.

Stealth Exhausts are normally not designed to be specifically a sports system, as they are normally intended to replace the standard system when it fails. Our YozzaSport Stealth system was always intended to be a replacement for the OEM system. We used the same centre section as our sports systems to make the backboxes interchangeable for the customers who wanted to fit the race systems when they were on track.

Click here to buy a >> 172 Stealth Exhaust <<

Sports Exhausts

Most sports systems that you will find will be either 2.25″ or 2.5″ systems for the 172 and 172 cup. The 304 stainless steel systems that we sell are as good as new 2 or 3 years on from when they were first fitted. Mild steel systems just aren’t worth the money.

We offer two systems for the 172, one has a 2.25″ Backbox and the other a 2.5″ backbox. They share a centre section (2.5″) and are completely interchangeable.

With a 2.5″ Decat the 2.5″ System normally produces between 8 and 10 bhp on a standard engine.

Stainless Steel Exhaust Manufacturers

There are a number of options in terms of manufacturers including; Ourselves (YozzaSport - Our systems are made exclusively for us by JP Exhausts – we can put you in touch to get fabulous deals on other types of system other than the clio systems) OMP,Supersprint, Orbisound, Magnex (who I think might be out of business as of late 2008), Blueflame, Milltek, ProSpeed and Hayward & Scott, as well you having the option to have a custom stainless steel exhaust made by someone like powerflow, the biggest problem however with powerflow is that the different dealers up and down the country can vary tremendously in the quality of the systems that they produce – they are only as good as the person who makes your system. I am sure that I haven’t covered all of the manufacturers, however, that is not the point of this excercise.

I hope that this helps you find the right system for your 172 or 172 cup.

Always a Hooligan,

/y0z