I am considering buying an Exige but want more power that the 177.My research to date has returned the following, does anyone have any comments?Resonator valve and butterfly filter on the intake.Exhaust - standard is sports, motorsport one is lighter, shorter, louder but with little power increase.Cat bypass pipeCatchment tank and silicone pipes - understand the catchment tank, but the pipes??Fuel filler breather (recall) and charcoal filter??ECUCam pully replacement - why??Also, is there any more info on the following:K&N air filtersDry sumpingOil coolerSuperchargingIs there any advantage of the Carbon air box other than looking cool and being lighter?Is any of the above work (like the cat bypass, resonator valve removal, catchment tank fitment) possible for the experience home mechanic?Any info very wellcome - it seems the power upgrade stuff is not all in one place, or is it?
Well, Lotus offer a 190 upgrade, which makes the car plenty fast enough. (Still 250 bhp/Tonne)However, TurboTechnics offer 220, 240 and 260BHP upgrades too.I’m sure 330 BHP/Tonne is far more than adequate !I’m told the carbon airbox is 1kg lighter, whethere it’s worth the �400 … that’s debatable.The SuperSports exhaust saves you 11Kg as I recall (and therefore much better value for money than an airbox)… and while it doesn’t increase power, it helps increase performance by virtue of it’s weight saving.Depending on where you are… if you’re in the UK, I’d leave all the work for Lotus to do (and therefore keeping your warranty intact)
Firstly the resonator valve and butterfly has usually been removed by any dealer as this is only fitted to get the car through the Noise/Emmissions Test. It is apparently easy to remove if it hasn’t already been done.The Cam pully is replaced when having the Sport 190 upgrade, it is lighter and has a slightly different angle or something giving more torque etc. I think!!The cat bypass is pretty much easy to fit if it anything like my old Elise, you just unscrew the back part of the undertray and then unbolt the Cat and put the Cat replacement pipe in its place. I completed the change over in about 1 hour at most.The catchement tank is not really a performance upgrade as far as I know (correct me if I am wrong!) it is only for catching the excess oil etc. which is lost during hard cornering.Hope this helps in some way!!
The catchment tank, I understand it does not boos HP (some articles say .5-1HP), however the explanation of what it does is confused:Is it:1. For anabling the crank to breather easier, preventing the build up of oil vapour pressure in the crank, i.e. it breathes through a secondary tank. This would not improve lubrication during cornering (i.e. like a dry sump)or2. Part of a dry sump or partial dry sump to aid lubrication during long high speed corners.Mmm?
Go to this link, which gives you all the info you need on the 190 upgrade: http://www.exiges.com/ubb/NonCGI/Forum5/HTML/000008.html For simplicity, here is the excerpt on the breather/catch tank:Hose Kit - Lotus Part Number : A340X6013S Part List Price (plus VAT) 40ukpBreather Tank - Lotus Part Number : A340E6011S Part List Price (plus VAT) 60ukpConsists of small bore flexible blue silicone pipework and a remote 1 litre aluminium catch tank. The breather system allows non combustible gasses to vent from the engine into the catch tank which is open to atmosphere. The catch tank catches all the heavy crankcase fumes which are, made up of water, oil residue,hydrocarbons, soot and loads of nasties.As well as being a safety measure against in that it increases the in cylinder detonation limit and allows higher cylinder pressures to be run without detonation, the breather system allows the engine to operate with slightly enhanced output. Crankcase gasses effectively lower the octane rating of the fuel.In theory the catch tank should be emptied periodically although many owners have found it to fill at a very slow rate.It is also common practice for the fuel tank breather charcoal canister and plumbing to be removed. Vent the fuel tank breather pipe from the roll-over valve to atmosphere