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How about a 4x4 clio :) :)


just examined a 4x4 scenic gearbox...

You heard it here first lol...

it looks like a piece o piss fitment to the 172 chassis... (The transfer drive to the rear axle is located spot in the pseudo tunnel that renault made for the gearlever etc...

the rear would be fun - but a complete Sceney subframe (Galvanised even lol).. complete with viscous coupled diff - similar to vw synchro...


hee hee hee hee... might be a do-er after the turbo....

hmmmmmm again....

  320d M Sport

Listen ere Joe, increase your medication, seek por advice and stay off whatever the hell it is youre taking......

Give it a go, its only a £12K car youre playing with!!


ps- u at the rollin road in Sept then?

Nurse ! ???

thats it, your right.. its a 12k car..

I dont give a sh*t about the warranty, resale etc.. its all about driving something bloody quick.. that you have crafted...

well, it pulls my chain ...

Joe.. ps.. hmmmmm 3 piece propshaft with mounts.. oooooooo... looks a bit toooooooo easy this.....

Perhaps they modded the floorpan to accomodate a future 4 gripper ???

Dunno.. but it seems like they knew I was coming lol..


well, if your goin that way, stick another motor in the rear....or just make it RWD.

but dont make it too heavy!!!
scenic gear!!!
jeez, mad man!

hee hee

nooooooooo, its a very light subframe in total, and you lose all the original.. in weight its about a 1-1 swapout + 20 Kilo..

its on the back.. kewl...

now for some serious stuff lol... anorak on...

heres a graphical overlay of my plotted figures on an MHI TD04 turbo housing..... this will be the one I will use for the project.

the lines going up the graph (the straight ones - are plotted from my new spreadsheet (5am this morning OUCH !).. crappy layout, but seems to work...

they are a plot of airflow through the engine at a specific pressure ratio

the lines represent 2000, 3000, 4000, 5000, 6000 and 7k plots for pressure ratios from 1 to 2.7

to work out boost...

boost pressure= 0 to 14.7 * 2.7(pressure ratio chosen MAX) - 14.7

so... the verticals are the rpm plot against cfm of airflow (how much air ya have ta pump lol) - at a given pressure ratio.

the bottom line is this..

if the plot lines fit within the compressor map from the manufacturer.. and dont go too far left (Surge and Stall) and too far right of a line drawn vertically from the max flow point.. then anywhere past that line is fine ! (that line isnt drawn on the map.... you need to add it... anything up to the line is fine.. above that you reach compressure build up.. ie, it cant flow anymore..)

we have a turbo suited to the engine charactersitics of a clio 172... ar boost pressures from 0 - 25 psi !!!

as an idea.. at 6250 rpm (max bhp on a 172) at a realistic intercooler outlet pressure of 23 psi.. then the cfm requirements of the compressor are multiplyed by the ratio of the pressure increase.. the engine still only breaths exactly the same CFM as before.. but this time the air is twice as dense.. but we get more gogo

How much power ??

How about....

engine hp potential 295.7 hp @ BSFC=0.7
engine hp potential 345.0 hp @ BSFC=0.6
engine hp potential 413.9 hp @ BSFC=0.5

the BSFC for this unit .5 (more or less)

lets presume .5 at boost..

hmmmmmm.. wheres me big strap for the main bearings LOL..


)ps.. the map fits kewl.. the 2000 rpm line (at the left) is skewed due to a bug in me math ...

will look at it tomorrow when I have not been up too long..>


U R a mad mother. I thought I was intelligent?????. How is anyone going to follow U.

For me, back to basics please. Hell, whatever it says it has to be the best.

If u can do it Ill just let u play with mine (the car that is)

PS sorting our day out hopefully

Regards Mark
  BMW 320d Sport

joe youre on the right track with the 4wd. Do it. Thats the one big problem with fwd, you can make as much power as you want, but laying it down is another matter.

Two questions Joe so you are going to use this compressor housing?. And how much is this 4wd going to cost you? lol. Your mad Capt. Hmmm 4wd clio , youve got me thinking


Had a look at the site that m@thew got his compressor flow map from and was playing around with the Air Flow/Fuel Flow calculaters. And using the VE figures from your previous post I got these figures for CFM at 2000rpm for the 172 engine.

Pressure Ratio = PSI CFM
1.14 0 29.76
1.34 5 34.98
1.68 10 43.86
2.02 15 52.74
2.36 20 61.61
2.70 25 70.49

Anyway my question is Capt, is the calculator wrong on that site? or have I put in the wrong numbers?. The site uses this equation (VAF = (L/28.328) x (RPM/2) x VE) to work out the CFM. I put in L = 1.9881, RPM = 2000, VE = .37. VE was from your previous post. What do you think Capt?.


What Im trying to say is Capt if my firgures are correct, my figures are most likely wrong , that would make the TD04-18T housing a bit big?. Dont laugh at my figures and conclusions hehe its my first go with flow calculations. The calculator on that site made it a lot faster to do those sums tho.


Nice one Chun..

my formulas are..

convert litres to Cubic inch

= (litres-capacity*1000)/16.39

and vaf= capacity in ((CI/144)/12)*rpm/2)/100
multiply lot by VE.

long winded,b ut fits the other calcs in the spreadshert I wrote

They produce the same reuslts though

The ve line at 2000 has been updated in my spreadsheet - heres a shot of the latest page

the grey box at the bottom and the graph to the right is the first attempt at producing overlays for known maps.

From my early post, I had decided the ve was too low and that is relected in the figures.

With a low line on the 2000rpm scale against VAF to pressure ratio the line is too far into the surge/stall area.
however, the newer line is shoving it into efficiency. all other lines are smack on.

So, the end result is that the 18t would be good (or appears to be)

The later scoobies use the same exhaust turbine housing, so I need to find out more about their flowmaps..

but, best line up is the 18t.. (so far!!!)

so, your math is correct, its purely down to the ve at 2k line.. to correct this anomoly I need to see other actual plots of torque for a 172 where the operator of the rollers has used WOT to accelerate at lower engine speeds.

I will ask Ken at RE Bury to do a fixed rpm max power plot on mine as is to get a better torque curve to work out torque ramp-up and VE from.

Glad to see you are following along.. please offer any suggestions along the way as 2 heads are better than 1 lol.


Saw in one of my daughters max the for sale section, 350bhp cosworth powered valver with the sierra 4x4 running gear. Now thats a car I would have liked.

Captain-one question, how hard will it be to convert a megane coupe using scenic 4x4 gears, would it be a straight swap as theyre basiclly the same chassic?

Cool Nice to know I can do a little maths How much are these housings?. What I wanted to ask Capt is that if you did a mapping on your ECU for the power you wanted and I was after less power would this map still work but with less boost?.



BTW Sorry for asking so many questions.

Hi Monk,

I would imagine it is fairly straightforward but am unsure as to the intricasies of the megane.

If you want any parts let me know.

I have 2 gearboxes and 2 complete rear subframes with diffs,, *but, unfortunately they are not cheap..

mail me at if you are interested.

Chun.. hi m8 !.. yes. !

  Clio 197

Yes we need a car like this. But we need it to be built by Renault to Gp N regs. This way it would be affordable. I am sick of the new WRC formula where the like of Ford, Skoda, Citroen and Peugeot get to build these one off "funny cars". Renault at least had to build a bunch of R5 turbos and Clio Williams to homologate them. Then the rest of us got to play with the extra ones. Unfortunately with the new rules they only have to make the competition cars and nothing filters down to us.