There is more to life with TurboRenault.co.uk

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Aussie-based 2010 Laguna III Sport Tourer 2.0T

Dave200

New Member
First time posting. Pretty rare thing over here, especially being the wagon (estate) and having the F4R turbo motor. We have a great Renault Sport community here in Australia but info on some of the less common Renaults is hard to find. I have seen a few helpful threads on here which is what spurred me to sign up.

Its done 85000km which is nothing at all and has some minor mods like aftermarket wheels and lowered 45mm on Pi springs.

I'm keen to understand what F4R is under the bonnet. It is the 125kw (170bhp) version and I believe the engine code is F4R811. The turbo pipework is routed differently to the mk2 Megane RS, it comes straight up in front of the inlet manifold on the passenger side rather than routing over from the drivers side.

How capable is the engine in terms of tuning? Is it possible to get it to Megane 225 power safely? I believe the transmission is rated to 330Nm so should be safe with more power and torque.
 
pretty sure all the conrods are the same on all f4rt's

the 170bhp engine has a smaller 10t turbo and injectors (plus higher comp from memory) than a meg rs. tbh id slap on a 14 or 15t turbo, some r26 injectors and give it a map. Will prob still be good for 250ish bhp.

If it was the 205bhp version its the same engine as the r26 (inc turbo cams and injectors)
 
Thats a pretty good looking estate!

@Brigsy might be able to advise on tuning, I suspect the con rods will be the weak point.

Thanks mate!

pretty sure all the conrods are the same on all f4rt's

the 170bhp engine has a smaller 10t turbo and injectors (plus higher comp from memory) than a meg rs. tbh id slap on a 14 or 15t turbo, some r26 injectors and give it a map. Will prob still be good for 250ish bhp.

If it was the 205bhp version its the same engine as the r26 (inc turbo cams and injectors)

good to know, thanks. I guess with the higher CR it will need to be tuned carefully. Will the intake manifold be sufficient or would this be better off coming from a 225 or 250 motor?
There are quite a lot of Megane RS' here so shouldn't be an issue finding a wrecked one.
 
Welcome to the club.

See what size turbo is fitted, part numbers are on the inlet side. Compare compression ratio and cams to the 205 model.

Intake manifold will be fine. I know a 205 of the same shape will tune the same as a megane 225.
 
intake manifolds and tbs are all the same. my old 300+bhp twingo was a 205gt engine to start with. 250 manifold is a different fitment i think @Brigsy can confirm

only thing on yours is that turbo outlet pipe, it splits underneath at the joint very easily
 
Welcome to the club.

See what size turbo is fitted, part numbers are on the inlet side. Compare compression ratio and cams to the 205 model.

Intake manifold will be fine. I know a 205 of the same shape will tune the same as a megane 225.
Cheers!

Turbo is a TD04-10T-8.5. Compression ratio is 9.5 according to Diagolys. F4R-774 (Megane 2 RS) is 9.

Also according to Dialogys:
  1. cam lobes are identical to the 774.
    1. Inlet is 40.647 to 40.707
    2. Exhaust is 40.607 to 40.667
  2. Valve springs have a slightly larger diameter
    1. 26.78mm for 774
    2. 27mm for 813.
  3. Valve lift is identical to the 774.
    1. inlet is 9.33mm
    2. exhaust is 9.25mm
  4. Pistons are slightly different
    1. Piston diameter at the ring lands are very slightly different depending on the spec of the piston used in the 774. Always the same piston for the 813. Maybe some leeway for piston choice when the engine is built for an RS...?
    2. Piston skirt is identical
    3. Piston heights are identical
    4. Valve recesses and combustion face identical
    5. Gudgeon pins are identical
    6. Compression, sealing, scraper rings are identical
  5. head gasket much thicker on the 774
  6. Con rods are idneitcal
 
only thing on yours is that turbo outlet pipe, it splits underneath at the joint very easily
Yeah it looks of similar feable construction to the mk4 Clio RS which is known to split as well. Moving to a Megane 2 RS set up would be a good idea but would need to check the cooler fitment on the Laguna as it looks a lot smaller than the Meganes
 
Id be tempted to change headgasket for megane rs to drop the compression ratio, fit 14 or 15t turbo and you should be up to stock meg rs power levels with a good map.
 
Id be tempted to change headgasket for megane rs to drop the compression ratio, fit 14 or 15t turbo and you should be up to stock meg rs power levels with a good map.
Yeah cheers, they changed the CR in the easiest way possible for modders :)

May just leave the head gasket alone though and keep the higher CR and ensure any tune is still relatively mild. Not after massive power, just a little bump over the measly 170hp. I used to have a Megane GT220 estate and that was a much handier car.
 
Interesting to note that the intercooler on all turbo F4R Lagunas is identical. The GT with the larger turbo from the Megane RS uses the same intercooler and pipework as my Laguna 2.0T.

The intercooler on the Megane RS is a lot bigger and a different design in terms of where the charge pipework meets the cooler.
 
Megane rs mk2 and mk3 stock oem intercoolers are poor. Thats one thing to look at upgrading.
Im pulling the front bumper off this weekend to fit new headlights so i’ll take a good look at how the existing one is mounted. There is absolutely nothing in Dialogys about the intercooler or how its fitted
 
Back
Top