Inlet manifold RS vs. non-RS

[FeelX]

Browsing the world wide web for information about the inlet flowing and stuff I found this french site.

http://cliors.xooit.com/portal.php

My French isn't the best, but babelfish is so great.

Anyway on that site there is a thread about the flowing of the inlet manifold and plemun just like on Cliosport.

http://cliors.xooit.com/t1647-admition-cale-porte-injecteur.htm?start=280

A member of the French site has experimented with the inlet manifold by RR-ing his standard RS ph1 and then fitted with the Cup (RS on inlet manifold)

Apparently the result seems to be a bit strange, but I will explain later. The darker line (blue and red are from the RS-inlet)



As you can see there is a drop in torque and bhp at the lower part of the rpm range. Reading on in the thread (using the babelfish translation) the user mentions that the drop in torque and bhp solved itself because the ECU had to readjust to the new A/F-ratio. (I can only imaging this when the battery isn't disconnected while working on the car)

The RS-inlet manifold was measured at a width of 48mm and the original inlet was measured 45.9+mm (this was on both sides - engine side and plemun side) For more info use the search button

I also found a site where a user did a DIY-job at the inlet manifold matching including (de-)mounting the inletmanifold.

http://64.233.183.104/search?q=cach...te+injection+clio+rs&hl=nl&ct=clnk&cd=2&gl=nl

Anyway I was wondering if the drop in torque and bhp has been notice by anyone that had a matched/flowed manifold fitted?

Also this post is purely informative.

 

[Dan172+]

When mine were done, the difference out on the road was fantastic, picked up far better than before..

That guys job looks abit dodgy with that drill bit:S lol! id send it to a professional outfit as if you do a search you will find a thread by ben r from angelworks. As he says, they had to do alot of r&d and test manifolds before they got any gains at all with a cnc machine, so id imagine that going at it with a drill attatchment would, 9 times out of 10, f**k it right up!:clown:

 

[FeelX]

Yeah I thought so, I never was planning on doing it myself, but the RR result of a RS inlet and the inlet without the RS logo/sign, seems a bit odd to me.

Just posted the DIY link so people could see how to undo and mount the inlet manifold. (BTW you have to scroll down all the way in that thread)

 

[mattjk]

Thats cool - dont know if id attempt it myself tho lol

 

[GordonD]

So the dyno showed a drop in torque.

But we're supposed to just believe that later on the ECU sorted itself out and fixed that. Yeah, right.

Reduced torque is exactly what you're likely to get if you just open up ports to as big as they can go. We live in the age of precision casting and CNC machining, and the Clio Sport is a performance model that gets special attention. If Renault engineers though that that just opening up the ports would produce more power without any cost to low-end torque and driveability they would simply have programmed the CNC machine to do that.

And even matching ports may not work the way you think. Its usually a good idea with where the airflow is feeding straight into the port, like if you had ITBs. But where the air has flow around a sharpish curve how the air flows depends on how fast its flowing. You will want as good a match as you can possibly get on the outside of the curve, but you may actually get a better combination of both top end AND bottom end if you have a step on the inner side of the curve that blocks reverse flow in low flow conditions.

 

[FeelX]

@ GordonD,

I understand you totally, when DIY matching the propability of f**king up and having less torque and stuff is like 90%

Anyway the RR isn't with the DIY matched inlet manifold, but with an RS marked inletmanifold. (first run with a PH1 manifold and then with the RS marked manifold)

I would like to have seen a RR with the DIY-matched inlet manifold tho.

 

[en035]

RS one's have bigger ports but that does not necessarily mean they match perfectly.

Just speculating now, the RS one might have horribly matched ports.

I have got mine done by a professional tool designer. Since he is my friend he spent his valuable time on doing that. Results are very very good.

 

[Dan172+]

RS items have better matched ports than the others, and flow much better, but having them done properly by angelworks is better still, though if you have the rs one already, you will notice less of an improvement than if you had an old item matched, as less material is removed...if that makes sense Do a search