Lpg

[Stimpy]

Has anyone here converted their stag to LPG?
If so can you tell me the expense plus the pro and cons?

As ever - thanks folks!

[martin]

Expense ? a lot, pros ? cheap fuel if you can find it. cons? no boot space left, cutting hole in body for filling. As soon as our beloved government catches on, LPG will match petrol in cost. Too much alteration to a classic car. Martin.

[Rubce]

Install the tank(s) in the bottom of the hood stowage area. That way you don't loose any boot space and provided you choose the right size tanks it won't affect the stowage of the soft top either. Conversion to LPG is on my list of things to do but it will have to wait until I work out how I can fund it!

Bruce

[ChasR]

Or lose the Spare and install a toroidal tank. A much tidier affair . As for expense, not as much as you may think. As long as you are competent with the spanners most could install an LPG kit adequately. Indeed, I have seem some poor conversions from reputable companies but I guess that exists in any line of work.

I did almost buy a Dolly Sprint and convert that to LPG. It does not help that my dad and I used to convert cars for a living (my daily runs on LPG ).

[Stimpy]

Some superb answers and there seems to be a real divide (amicably of course!!)

Believe it or not I use the Stag the year round- we probably cover 12k miles - meaning 4 oil changes (do I *really* have change the oil filter every singe time?)

Ok some questions, please -

1) Can I keep a petrol tank as well?
2) Is it really obvious / etc
3) How many horses will I lose?

Now the big one....

Fitting and parts - please tell me quietly !!!

Cheers !

[ChasR]

Yes, the petrol tank will be unnaffected. You may need to interrupt the wiring to the fuel pump so as to switch it off when you switch over to LPG (on carb cars it tends to be a 3 way switch for switching between the two fuels (1 position to run on petrol, another so that the fuel can be emptied out of the fuel floats and a 3rd position for running on LPG).

Nothing will really be obvious. What will be most obvious will be a filler cap which has to be outside the car (for LPGA rules anyway). But you can get around this (mount it underneath the car). In the engine bay you will have a couple more hoses present, in the form of coolant hoses tapped off your heater hoses, two more gas hoses going to the mixers in the carbs and a vapouriser (what converts the LPG into a gas state for the engine to burn/use).

In terms of horses around 10% decrease in power is the norm. But depending on how well it is setup that can go down. It really does vary from car to car (My 3.0 Mondeo feels no different running on LPG yet my sister's 2.0 feels slightly down (by a small margin)).

As for parts etc. I would expect it to come to less than £1k from most places being a simple mixer system. As with anything the initial price is a small price to pay. How reliable the system is in the long run should be the main question.

[the tim]

lpg

my friend did one ,a few years ago,run like a dream , i will try an get some info for you

[richardthestag]

my daily driver Range Rover (1993 3.9 EFI) runs LPG. single point, closed loop (takes mixture reading from Lambda sensor in exhaust to run more efficiently)

Bugger all difference in power, in fact it runs smoother on LPG though idle speed is sometimes affected. worse MPG though.

On a good run on unleaded, not too heavy a right foot at motorway speeds the old Rangie might see 23mpg, on LPG 17mpg is nearer the mark, and I have never bettered 18mpg. Round town is nearer 13mpg. A spirited 1700mile run to the south of France and back this year, fully loaded with kit, 4 bikes on a bike rack, and carrying the misses and 3 sons saw it average 15.5mpg over the whole journey. LPG/GPL used to be a lot cheap on the continent. Not any more though!!!

That along with the closing price differential between unleaded and LPG means that running costs are only slightly better on LPG than unleaded. Fortunately my kit paid for itself many years ago. My Stag MoD can get near on 30mpg on a good run and for the mileage it does each year the kit would probably never pay for itself.

I bought my kit complete from TinleyTech. I cannot recommend these guys highly enough for their expertise and advise.

I fitted it over a long weekend and got TT to inspect my install and give it a certificate of compliance – needed that for my insurer.

Only problems that I ever had with it were a dodgy airfilter which caused too much vacuum the wrong side of the mixer which meant that the car ran great on petrol but not at all on LPG.

Also the ignition and general engine health will need to be tip top. Any slight issues especially with ignition will mean that LPG will not function or backfire through the carbs and rip the airfilter apart.

You could install a Toroidal tank in the spare wheel well. Or replace the petrol tank with a smaller custom made boat tank and install a bigger torpedo tank under the boot floor. Not sure on the dimensions. Where you put the spare could be an issue. In the RR I have a vertical toroidal where the spare used to sit. The spare now sits flat on the boot floor.

Have fun

[tonypy1]

I fitted a kit myself to a 4 litre Jag XJ8, cost me about £850 for the "mutt's nuts" fully sequential system with an 86 litre tank. A Stag install would be much simpler, the hardest part would be routing the copper lpg pipe from the boot to the engine bay unless the flexible stuff is still available and then it would be fairly easy. You'd also need a lambda sensor in the exhaust unless you wrere going very low tech. A self install kit could easily be fitted to a Stag for £400 particularly if you used some second hand bits. You'd then need to pay about £60 for a safety inspection, my insurance premium price was unaffected.

I didn't notice any difference in perfprmance on the Jag, it went like stink on both fuels however, the economy went down from about 24 on the motorway to about 20 although this could have been improved at more sensible cruising speeds. I'm not sure what the performance difference would be like on mixer setup needed for a stag with carbs.

I fitted the tank in the spare wheel well and doidn't bother with the spare, I just carried a spray repair can instead and was lucky enough not to have a puncture in 40,000 miles or so after I fitted the kit.

The ultimate solution would be an EFI TV8 that could then be adapted fairly easily to run a fully sequential LPG setup.