Well I finally got my HHO kit fitted and working - had a bit of a problem with a leak on one of the pipe outlets from the Gas generator which took a while to fix however now it is all plumbed in and working and generating Hydrogen. First impressions. Well for the first 100 or so miles there was a noticeable increase in engine vibration but that seems to have calmed down now to where it is actually running smoother than before. I guess this must be the ECU learning the correct micture. In terms of power, a little bit better lower down and quite a bit better mid range but not noticeably any different at the top end. Fuel economy, well I have only done one decent run with it but did a measurement from light on to light on with £30 of fuel - unfortunately quite expensive motorway fuel at that - £1.28 per litre. Did 140 miles of which all but 4 miles wereff the motorway, general speed on the motorway was 80 ish (well 69mph officer honestly). Works out to 27.06 mpg which I don't think is bad, wld have probably got less than 24mpg at that speed without it on. Will do a few more measurement runs it beds itself in, I have heard it is quite good at burning off the old crud in the engine. Might give the old girl a good dose of Redex to give the injectors a good sort out. One other thing, the engine as 165K miles on it on the original injectors.