Renault Clio 4 RS Mod Journal

Xcede if giving the Renault Clio RS owners some love. Let’s start with a bone stock, zero hardware on pump fuel. Car was run stock then flashed on the dyno and run again.

Car was then mapped on the dyno.

And with the same fuel, no adaptation time, this was the result:

With a conservative map in order to preserve the gearbox, there was still a very healthy gain.

Next we put the car on a ramp to see what Renault RS division had done with the exhaust. To be totally honest it’s not bad given the constraints they had to work with and it works pretty well.

But where there is an opportunity to flow and introduce more efficiency, it has to be taken. So out with the secondary catt!

And onto the primary catt:

Like I said, modern cars are designed a whole heap better than a decade ago and even though the stock downpipe had a horrid 90 degree bend in it, it was still designed and flowed pretty well. The stock was diameter was 53mm and we fitted a 63mm 304 stainless steel pipe and reduced that bend as much as we could to produce a much free-er flowing design to ease the pressure on the turbo.

And then back onto the rollers to verify the results:

A peak gain of 4kw at 7NM, as expected when I said the stock design looked pretty good. But that doesn’t tell the whole story.

The red line is before the downpipe and the black line is after. Look at how much quicker the turbo spools up due to the optimised design. The dyno starts at 2000rpm and already there is a 60NM gain ON THE WHEELS at 2000rpm! There is a healthy 40NM gain all the way to 2600rpm. Transforms the drive at low rpm and dramatically increases the engine responsiveness.

And at high rpm there is an average gain of 10kw on the wheels from 5000-6000rpm. Revs much more freely and crisply. And sounds magnificent as well. Definitely a worthwhile improvement over stock.