supercharged 4.2 engine on lpg
Discussion
I think if it is done by someone who has done a few and it Is done properly with a plumbed in flashlube kit and the correct injectors etc you shouldn't have anything to worry about.
Im not sure if their would be much difference in fitting the kit between the models that have this engine though, perhaps someone else will jump in and offer up a little more information.
I have a XKR 4.2 on LPG. This is my first LPG vehicle. If you search around on the forums you will find various stories relating to this engine on gas, some doom and gloom others positive.
As far as I understand the biggest differences between the vehicles this engine is fitted to is space under the bonnet, with the XK8 shape there is not much room with a Range rover sport or XJR you have some more space to work with.
Unless there are new bigger single vaporisers on the market now you can't get one that can deliver enough gas for 400+hp. You either need a twin vaporiser set up or have a system that is a bit of a compromise and uses petrol additions to make for the short fall. As you can't legally drive one of these hard enough to be in the higher rev ranges for long I didn't see this as too bad a thing to have and it made a significant difference to the conversion cost.
any system that uses AEB s/w should be able to deliver petrol addition.
It will need a petrol return pipe fitting.
Flashlube is again something that some people swear is needed for this engine and others claim it isn't. If you fit it you need a electronic delivery system that physically pumps it in after the charger and cooler. My fitter claimed to have run several V8's for 100's of thousands of miles without flashlube and no issues. I took his advice and went without. I have also since read articles that indicate that petrol additions can help hear. The key thing is not to run lean!
so far I have done around 25k miles on gas. There have been some issues, nothing too worrying but having the installer local so I can call back in is handy.
The fact that it cost less in fuel to run the 4.2 s/c than it does my 2.0l mazda 6 always makes me smile.
As far as I understand the biggest differences between the vehicles this engine is fitted to is space under the bonnet, with the XK8 shape there is not much room with a Range rover sport or XJR you have some more space to work with.
Unless there are new bigger single vaporisers on the market now you can't get one that can deliver enough gas for 400+hp. You either need a twin vaporiser set up or have a system that is a bit of a compromise and uses petrol additions to make for the short fall. As you can't legally drive one of these hard enough to be in the higher rev ranges for long I didn't see this as too bad a thing to have and it made a significant difference to the conversion cost.
any system that uses AEB s/w should be able to deliver petrol addition.
It will need a petrol return pipe fitting.
Flashlube is again something that some people swear is needed for this engine and others claim it isn't. If you fit it you need a electronic delivery system that physically pumps it in after the charger and cooler. My fitter claimed to have run several V8's for 100's of thousands of miles without flashlube and no issues. I took his advice and went without. I have also since read articles that indicate that petrol additions can help hear. The key thing is not to run lean!
so far I have done around 25k miles on gas. There have been some issues, nothing too worrying but having the installer local so I can call back in is handy.
The fact that it cost less in fuel to run the 4.2 s/c than it does my 2.0l mazda 6 always makes me smile.
Gassing Station | Jaguar | Top of Page | What's New | My Stuff