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How to build a genuine 300+ Turbo Clio

Right chaps this isn't really a guide as such, its a complete spec list of what I've found works well on a clio. I've had tons of PM's over the last couple of years regarding Turbo clios but have always kept my true spec quite quiet, anyway here goes.

I took my completely standard Trophy lump and did little more than fit a set of CatCam rods, a set of Wossner pistons and a set of megane R26 OE spark plugs

It's well documented on here that after destroying my OE box I swapped to a JC5-128 DCi box. I found it a great set up for a genuine 300+bhp clio on both road and track, AndyRG tried one when his clio was around 270bhp and hated it. Based on this I'd stick with an OE box sub 300 bhp.

I stuck with the OE fly wheel but ran a Helix paddle clutch. I'm not going to lie it was horrible, there was very little pedal travel from fully disengaged to fully engaged which resulted in everyone who ever drove it stalling it repeatedly. I would also say the longetivity of them wasn't overly impressive so it's something to bare in mind. It does work though and I didn't experience any slip or issues on either road or track

I used a Forge type 7 200 series universal intercooler it was the largest unit I could squeeze under the front cross member but I did have to remove the small plastic undertray that runs from the front bumper to the subframe.

Pipework wise was a bit of a ball ache, there wasn't anything available off the shelf at the time and I wanted 2.5" pipework, so I bought a stainless universal kit off ebay and set about painstakingly cutting each bit to the correct length before ordering the suitable silicone hose. Since then Ktec have a kit off the shelf and personally I'd save yourself the headache and just buy that or pay for a custom hand made set up.

Ktec turbo down pipe, turbo link pipe running into an ultra performance single box de-cat'd exhaust. It was basically 2.5" from the turbo back with only the single back box causing and restriction. Again it worked really well and was suprisinglt quiet. Other options would be to get a custom turbo back exhaust with a flexi joint.

This is the area which gives the biigest problem but has the benefit of shaping both the overall power and also the characteristics of your power band. It's pretty straight forward, the bigger the turbo you choose the more power you'll make for a given boost pressure, the trade off is it'll spool later and you'll lose out in the lower rev range. Because of this you need to be honest about what sort of power your aiming for, it's no good fitting a 600bhp monster turbo but the rest of your set up only capable of flowing/supporting 350bhp.

I ran 3 turbos during my tinkering.

First off was Ktecs own GT28 I found it extremely restrictive (I had a 2.25" exhaust and the stock cat which won't of helped) and it gave a very aggressive spool up due to running high boost (22psi) to try and make good power. The result was 267bhp. One thing which was a problem was the ECU but I'll cover that later.

The second turbo I used was a GT2860R it was basically a GT28RS but with a more compact GT28 compressor housing (two bolt inlet and three bolt outlet shown at the bottom of the link) this is by far the best turbo I used. I ran 341bhp @ 1bar (14.7psi) of boost. It gave a really responsive but smooth power delivery and best of all when running only actuator pressure (7 psi) it made 280bhp. It also allowed the use of the larger T3 style actuator which in it's self helped to eleiminate some of the boost problems I experienced with the T2 actuator found on ktecs turbo.

The third turbo I used was a GT2871R again I chose the compact GT28 housing. This was a bit of a disappointment. I'd heard so many good reports from them being fitted to 200sx's so assumed it would blow me away. The reality was it spooled later and slower due to the larger compressor wheel and made the power delivery more aggressive than the GT2860R with 1.2bar of boost it made 374bhp.

The truth is your limited to a T25 flanged turbo, also the amount of space means that you need to sacrifice a larger free flowing compressor housing for a smaller more compact GT28 housing or you can cut a big hole in the bulk head.

Manifold wise you can get them from ED or Ktec there both the same so the choice is yours lol

Initially I tried using the OE ECU and a boost controller but it was obvious from the outset that it wasn't suitable so I swapped it out to the EC1 supplied by RStuning. This is probably the key to making a real usable FWD turbo car, whilst using the OE ECU and a boost controller no matter what throttle was being applied the boost controller was always aiming for full boost. This meant that steady throttle or small throttle openings were met with quite a jerky response. By using an aftermarket ECU and giving it full control of the boost, it was possible to have a Boost Vs TPS map. This meant that whilst on 50% throttle I only got 50% boost. It provided exceptional throttle response and almost eliminated traction issues.

When doing it I wouldn't scrimp on sensors, I had a chinese copy of a MAP sensor start giving false readings to my ECU causing the car to run stupidly lean, luckily I have a data logging and monitoring system so spotted the high EGT and AFR's, be warned!

Uprated engine mounts
Oil Cooler
Uprated Coolant Hoses - they have a convienient join near the heater matrix where you can run a water feed through the turbo to aid cooliing
Data logger/monitor - allows you to keep an eye on essentials whilst enjoying yourself EGT's, Boost, AFR's, AT etc.....
Brakes - I run a JamSport set of Willwoods with DS2500 pads and HC discs. Great bit of kit and fit under 15" wheels
70mm Jenvey throttle Body
Heat protection - the turbo sits very close to the brake lines and the dwn pipe is close to the PAS so it's vital to have some high quality heat protection on the bulk head and rack. I used nimbus sheets and also had my turbo manifold, turbo and downpipes ceramic coated.

Gearbox problems - if you build a 370bhp clio turbo your gearbox will break if you use it with intent. I destroyed my OE box (literally destroyed), my DCi box spat the circlip out at 341bhp and with a new one welded in it was spot on. However when I moved to 374bhp and the more aggressive power delivery it wasn't long before 4th gear stripped :( I'd suggest a reconditioned box to aid longetivity probably with some strengthening mods.
Clutch - as above if your horsing it about your clutch will last less than 10k miles, if you use it on the drag strip expect signifuicantly less
Mapping costs - mapping costs a bomb, try and get it right first time rather than making small changes and needing multiple maps
Consumables - Oil's, gaskets etc.... soon amount up to a pretty penny so take your time and nail your engine build from the off theres nothing worse than having to drop £70's worth of good oil because one of you gaskets is weeping and you need to strip the engine down. Some people would reuse it but remeber that oil runs through you turbo so any crap in there could cost you your turbo.

That pretty much covers it, all the above is what I've actually used to make a genuine 300bhp+ obviously it's not the be all and end all of it. I'm sure there are better products out there (its been nearly two years since I built the above) but the above works. All figures are based on a F4R lump that was still running PAS and AC so simply deleting either would give an increase in power.

Hope the above helps people who are genuinely considering building a Turbo Clio


The Boosh!

ClioSport Admin
  Elise, Duster
Good thread Steve, could you put it in cliosport guides as well? I tried to copy it across but failed.

Sorry to the two people who commented :eek:
  Arctic Blue FF 182
Great write up! Been wondering for quite some time what your set up was! Nice to see someone playing around and not just grabbing something of the shelf! Top work!
  172 cup, Impreza P1
Very good read and info, cheers.

I'm nearing the stage of getting mine mapped soon so some of the info has helped confirm my thoughts on a couple of issues.

Thanks again!
Maybe a costing list along with the specs might be great for people looking to DIY!

Really good wrote up though, extremely useful!
  KTM 990 SD / S60 D5
Just roughly priced this up based on the links provided £6423.83 plus mapping costs and unless you can fit it yourself a fair amount in labour as well.
Theres plenty of bargains out there lads, rest assured I didn't pay anywhere near retail for any of my parts so the overall cost was no where near what Doms put.

The first post is more of a guide so people know what there looking for.
  BMW 535d
I completely agree with this

I found the aftermarket ECu ran the engine so brilliantly. Sesnors are a big issues too so no cheap copies

Even silly things like making sure it is all set up to the boost you are running etc. I learnt the hard way and ended up frying 3 pistons and a head
Very good post Steve!

Im putting together my own turbo build and its costing me nowhere near to what the ktec or engine dynamics are charging so I can second that there are great bargains to be had if you know where to look.

Im using a garrett gt28rs and only wanting to push 230hp on standard internals until I can get a forged engine built. My question is, can I use standard management to map it on without having the issues you had with part throttle etc?

Also would a 10an oil return be suitable?
.8 feed restriction be okay?

I Forgot to add the fuel setup so here goes

I retro fitted a complete PH1 fuel line, sender unit and fuel rail set up. I used a 255LPH fuel pump and a 3 bar regulator along with a set of siemens 630cc injectors. This allowed me to run 374bhp at approx 75% duty cycle.


I've spoke to a few people recently and have been asked what I would build now, I would use a GTX2860R turbo from garrett (possibly with the GT28R comp cover). It has the spool of the GT28RS but the flow capacity of the GT2871R. The reality is the compressor wheel out flows the turbine wheel and the natural choke point seems to be around the 370-380bhp (with a .86 turbine housing) this would give you the flexibility to run approx 275bhp @ .5bar all the way to 375 @ 1.2 bar. I would retain the cast logg manifold but would ditch the "off the shelf" turbo downpipe, exhaust and intercooler pipe work. For less than the combined price of them you could easily get a full custom turbo back system and intercooler pipework made. The rest of the set up would be as above, the PH1 fuel set up is becoming hard to obtain nowadays so you might have to improvise on that front.
Suprisingly I was only at BTM on Monday for a quick catch up with Fred. My Trophy is at the fabricators still (1 year on the 2nd May:(), when I get it back I need to pull then engine out as I have some custom pistons and one piece stainless vlaves to go in. I haven't decided 100% on what cams to use but I'm looking at mildish ones as I want a sensible ish rev range and some decent midrange torque. But I will pop round when it's finished :D
  Clio 172
Handy thread this, it's given some ideas for my build, quick question, what were your charge temps like on the gt2871r?

Did you not find the cast manifold caused a lot of restriction and reversion?
I honestly cant remeber what the temps were and I've deleted my old data logs, I think they were high 30's/low 40's but can't be 100% sure.

Those were the exact problems I was having with the log mani at 374bhp, I don't think the small 53mm turbine wheel used in the gt28rs and gt2871r helped much either. I used an EGT probe and the exhaust temps were starting to get silly if we tried to push it any further.
  Clio 172
I bet your charge temps would've got silly high if you had gone much further.

A mate of mine is building an R5 with a Clio engine in it, he's gone straight to a GT3071R cus he's worried the smaller turbine wheel will cause too higher temps
TBH it was almost two years ago since I had this set up and all the problem I experienced were based around exhaust gas flow. The old F4R lump flows surprisingly well, I've not seen many others make 341bhp for 1 bar of boost. Who's your mate with the five? As I know most of the lads running f4r lumps in fives, in fact Ashy has a gt3071r on his F4R Five.
Last edited:
  182 cup / Audi s3 8L
Just read through everything. Epic read. Has caused some serious thinking..and assessing of bank account
  fast renaults
i also want to build a low cost f7r turbo in the future.

my biggest problem will be wich clutch to use.

anyone got tips?

i am aiming around 250 BHP and this engine will only run trackdays.
  fast renaults
i also have a r5gt turbo with 200bhp but this clutch cant hold the power so it thought
the f7r engine/gearbox would also have a problem getting this power on the road.

i think i also need a stronger pressure plate??

or will the original plate be strong enough?
  182/RS2/ Turbo/Mk1
Mine was a helix paddle and standard cover when this graph was done, and it did 10K miles like that:

  fast renaults
i see this is a clio172 i am building a F7R i think the F7R flywheel is smaller this means smaller clutch plate
the biggest problem I see is getting the engine power to the ground
anyone got experience with F7R turbo engine and in particulary the clutch to use?
  clio 182
did you use standard cams you do any head work with the head? and what about the bottom end bearings and stuff you uprate those? or use new standard ones? cheers