LPG Discussion Forum

I got my mpgs and mphs mixed up there..
I meant at 60mph on the motorway, it's doing 19mpg on LPG, which equates to around 34mpg petrol equivalent. The car is supposed to do 30+mpg on petrol.

Anyway i have started logging every fill now so I will report back urban usage soon.

Anyone let me know what size donut tank they have fitted in the new-shape XK/R ?

As it happens I have valvetronic minimum valve lift increased to 0.8mm (thru INPA). This means it is not in valvetronic at very low load. It uses throttle for that light load operation. Full valvetronic would fully control engine speed with valve lift right from 0.1 to 8mm, but in my case, their ...

Well, the car is modern and uses closed loop mixture control.
It actually has wideband UEGO sensors, so I'm not sure there's much I can do to alter the mixture?

I replaced one of the wideband sensors a bit ago, and it made no difference to the fuel trims on that bank. The other side looked like a ...

My 4.4i valvetronic BMW 545i (n62 engine) achieved 19mpg on LPG on mostly motorway at the weekend, driving at around 60 mph. This is equivalent to ~35mpg running costs if it were petrol. I'd expect better than that. Any ideas for what might be causing it? It's supposed to do 35mpg on petrol anyway ...

I seem to be getting 19mpg from my 4.4L valvetronic BMW 545i on LPG.
It's a heavy car (1800kg), plus two passengers and suitcases, and a boot full of computer junk,b but doing mostly ~60mpg on the motorway.
I'm a bit disappointed at those numbers!
It's supposed to do ~30mph on petrol on the motorway ...

hitman wrote:93 litre fits

That can't be right. In the spacesaver spare-wheel well?

Thanks. If I decide to do it, I may give you a shout to install some or all of it.
I may go down the route of hardened valves & seats, although the cost is an eye-watering ~£1,850 from JE Engineering. I haven't looked into it any further though.
I'd probably go for 2x KME Gold & KME Nevo Pro, since ...

aw don't kill my dream!!

is it a big problem on this engine? I wonder if used heads are plentiful just in case?

I can confirm that on overrun, a few seconds after the injectors stop, the ignition coils also stop firing, and the LPG system (KME Nevo) shows "IGNITION". It switches right back on though as soon as coils start firing, so I'm not sure if it matters? Maybe it's OK because I have hot-start enabled ...

I'm sure there's some reason why Faro are so chuffed with them, and as I say, some degree of freedom-of-rotation once done-up must be nice.

This PRV purpose is to prevent the 'low pressure' side of the gas system bursting in the event of a failure - reducer, hoses, injector rails. It usually set at something like 4 bar.
It may well never lift in the life of vehicle. But it isn't that unlikely either - typically a coolant problem ...

Yep, I believe so.
Wonder if anybody has experience of issues in terms of space, size of spare wheel well, etc.

Thinking it might be my next project in 2 - 3 years time.

Anybody converted the 4.2 litre supercharged variant of the aluminium-bodied new shape XKR ?
I know the later 5.0 are direct-injection, but not the 4.2 I don't think. There's a little space-saver spare wheel well too.

anyone used Faro's new-ish FastyFit fittings?
I'm not fully grasping how it works. It looks like the olives that come with your reducers/multivalves, are replaced with the quick-connect coupling that comes as half of the FastyFit kit.

lol....

Actually it is working from the ignition coil.. It reports RPM twice in the readouts, and I was looking at the OBD area!

According to the manual, it asks you to input the current RPM when you select Camshaft, and it utilises this to work out a divider.

The software works out the divider based on you telling it the RPM as it monitors the sensor.

If the crank sensor isn't a hall effect sensor then I guess that explains it!

Yeah that's true. I did think about that. Right now I still have a hose hooked up to it anyway from when I had the vacuum lines connected.