Long post ahead as this is a bit of a favourite subject of mine, Ive been making different inlet manifolds for a long time now.
Reason Im asking is that Ive just came across this thing on ebay:
http://www.ebay.com/itm/nissan-sr20...es&hash=item3f2dd34025&vxp=mtr#ht_1143wt_1179
I know it's for the SR20 engine, but if you look closely they are selling what is basically a rs2 inlet (except this is all aluminium) for 330 USD (roughly 220 quid). So, has anyone built a DYI rs2 inlet? HAs anyone reverse engineered one? I mean, if someone could sell an aluminium version of teh rs2 for let's say 500 quid it would sell fast I'm guessing?
So, anyone done something like this?
You can buy just the plenum bit from those inlets, a guy in the Vauxhall ten of the best team who's car I map makes them for vauxhall engines, I am sure I could get him to knock one up for a renault, but the problem that you will have is the base manifold, you are going to need a throttle body base manifold realistically as the standard one doesnt lend itself to this sort of adaption like the one on the vauxhalls does.
This is from another car I mapped with one one:
I did a slightly different take on my old 600bhp nova engine, using the plenum from an RS200 Group B rally car and a Jenvey throttle body base manifold:
In place:
Also I made myself one a few years ago as well for my williams engine using a chadil ITB manifold that a few people on here with have seen, its quite funny how similar it is to the JMS RS2 we have on our 182, considering at the time I made I had never seen an RS2
This is it with the plenum cover off so you can see inside it:
Complete with plenum cover on and going into its new home:
To do it PROPERLY like the RS2 is then the minimum things you are going to need are:
A throttle body inlet manifold to get the correct fitment to the head and a smooth transition from round to oval to suit the ports
(you can knock up a flange and crush some ally pipes to suit, but dont expect the same results)
Injector bosses placed into the inlet at an appropriate distance and angle
Individual trumpets, in either ally or carbon etc
(you can just miss them out and from the outside it looks the same, but it wont work the same!)
A plenum of appropriate volume and that will accept the clio throttle body
Fuel rail mounting brackets
Brake servo takeoff
Map sensor boss
Inlet temp boss
I dont think that the price of an RS2 is bad at all considering what you get and that you know it will work, the carbon plenum could be made in fibreglass or ally and take a hundred or two off the price, and you could use cheaper ally trumpets instead of the carbon ones, but thats only going to be a small saving too.
I think if people start trying to knock them up on the cheap, they are likely to end up with something that doesnt work as well or isnt reliable (sheet ally fabricated inlets fatigue on the welds over time with the continual pulses it is subject too during engine running)
Despite me having loads of experience of making and mapping various different designs of single throttle inlets over the years, when it came to getting one for our 182 (well it was a 172 at the time, we have changed cars but kept the inlet) I simply went and bought a JMS RS2 one, as I realised from how much it actually ends up costing to make your own, what a good value product it actually is TBH, I know that sounds like an advert considering what good friends I am with James Stone these days, but its the truth, if you price up all the individual components that are required to make an inlet to that standard, you would really struggle to do a one off for much less, and you are likely to run into lots of development to actually get it to fit right and work.