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LPG up-grade to start run on LPG

8K views 14 replies 4 participants last post by  shadow 11 
#1 ·
Hi,I have made a small modification to get my car to start in the morning on LPG ,it is working perfectly,I don't use petrol at all,it runs like a dream,it is doing 11/12 mpg on LPG @ 2.90€ a gallon
in Ireland the road tax is 56€ & classic Insurance ic 200€ & doing almost 22/24 mpg @ petrol price equivelant WHAT A CAR
 
#4 ·
I sold the Bentley Jean ,I did a rediculous amount of work on it & it cost me more than I wanted to have invested in it ,I got it a good home it will not need any work for a long time.I replaced it with a good Spirit which I love.
Kevin.
 
#5 ·
Yes it was easy,I just put a small Spring on the top to stop the arm from dropping down.
In the morning I turn the key on & off a couple of times then I turn it over foe3 seconds then turn it off & re-start with the accelerator open fully & it starts immediately.
DO CHANGE to LPG,it makes your car as cheap as a mini to run,I put up 500 miles a week on my last Bentley 8 as an every day driver and the more I drove it the better it got.i drove it 25,000 and it never let me down once.
I have retired so I am only doing 100 to 150 miles a week now.
The carb models are cheap to get converted,you don't need a fancy job.If you do get it done get a large tank,I have a 140 litre tank which will give 112 usable litres.In Ireland I can get it done for 1200€ with the big tank.
You do not need Lambda Sensors on the carb model,it does not make it run better or cheaper.
Kevin
 
#8 ·
I first started using LPG in 1977 on Mercs so when I wanted to get my Bentley done I knew exactly what I wanted so I got some prices in Dublin from €3000 to €1200
Half the guys had not got an idea about old cars.I found a middle aged guy from Lithuania who was used to carb cars I got him to do my one,he operates from Dublin 12 he is used to Rolls & Bentley's now.
If you want I can bring you to him.Or if yow are around Wicklow you can try my car & look at his work.Lt runs sweeter on LPG.
Kevin
 
#9 ·
Thanks for the kind offer Kevin, much appreciated. I don't think I'll be converting to LPG in the immediate future but will get in touch if and when I decide to definitely go that route. I have a limitation of 4000 miles per annum on my classic car insurance policy and I'm taking that into consideration also, Regards, Larry
 
#10 ·
Hi Kevin - you have obviously had a good run from LPG in your cars.

Unfortunately, I don't share your experience with LPG - I have a 2007 Jeep Commander 5.7 Hemi with LPG. About a year ago I turned it off and have run on Petrol ever since. I think 25,000 miles is about the limit before the problems kick in such as top end wear, valve seats etc, whatever anyone says. And the performance, both horsepower and miles per gallon, is massively better on Petrol.

I have heard it's easier for older, carburetor, engines - I know it's certainly easier and cheaper to convert them - this may be the issue I have with the Hemi. Admittedly, to get a proper, high tech sequential injection Prinz or OMLV conversion with valve saver drip feed on a modern engine like the Jeep, it's ~£2500. The pay back is too long, before even factoring in all the other costs and down sides, and, that £2500 is up-front cash, of course.

The other problem is, I might be imagining it, but I'm pretty sure the available filling stations are contracting - certainly in the UK - possibly because there are less and less conversions being done - The number of big petrol engined 4x4's and cars that used to be classic candidates for conversion, has dramatically decreased - they have faded away over the last 10 years as the performance and economy available from big diesels has made them pointless for makers to offer. It's no longer possible to buy, for example, a new Jeep like mine anymore, only diesel versions - apart from limited production super-high-performance models like the Jeep SRT or Range Rover SVR, Merc AMG. I certainly come across plenty of "out of order" pumps at the filling stations. Before I stopped using it I was doing more and more diversions to get fuel.

Also, I hate the compromises on performance and, of course, packaging (ie. where the tank has to go?). I'm going to pull the installation from my Jeep so I can re-instate the spare wheel.

So, for me, I'm not a fan.
 
#11 · (Edited)
LPG Jeep

Yes I take your point,on a lot of cars I would have an oil lube injection unit with LPG depending on the valve seating's & this will fix top end issues.As I said earlier,it is hard to get it done right,LPG is higher octane than petrol and if done correctly is as Good if not better on preformance.On your car I would have 2 evaperators (smaller size) with 2 lambda sensors & believe me you will not have a power loss.but you are into an expensive job.UK prices are much more expensive than Ireland to convert.IN a different LIFE ( 1969/73) a had 6 Taxies with 15 drivers running 7 days a week all the cars were on LPG ( merc 190,Vauxhall viscount's & straight six Zephyr's) I got good on gas,
TO GET PREFORMANCE you must fit 10 mm to 12 mm plug leads,they don't run right on standard 8 mm leads & a sports coil & advance it 1 or 2 degrees & fit hotter plugs,(I am using Iridium for LPG.on My Spirit.)
IT IS HARD TO BELIEVE but I am getting on average 12 mpg on LPG 50/50 city + motorway & I am not trying I just drive it.It sees 70 m.p.h all the time when on motorways
It does not do anymore m.p.g. on petrol which is 5.90€ & LPG 2.95€ a gallon.
Kevin
PS check your leads are 10mm,I get my ones made in UK from Mr Plug leads 80£,you can do it yourself for a lot less
Kevin
 
#13 ·
Yes I take your point,on a lot of cars I would have an oil lube injection unit with LPG depending on the valve seating's & this will fix top end issues.As I said earlier,it is hard to get it done right,LPG is higher octane than petrol and if done correctly is as Good if not better on preformance.On your car I would have 2 evaperators (smaller size) with 2 lambda sensors & believe me you will not have a power loss.but you are into an expensive job.UK prices are much more expensive than Ireland to convert.IN a different LIFE ( 1969/73) a had 6 Taxies with 15 drivers running 7 days a week all the cars were on LPG ( merc 190,Vauxhall viscount's & straight six Zephyr's) I got good on gas,
TO GET PREFORMANCE you must fit 10 mm to 12 mm plug leads,they don't run right on standard 8 mm leads & a sports coil & advance it 1 or 2 degrees & fit hotter plugs,(I am using Iridium for LPG.on My Spirit.)
IT IS HARD TO BELIEVE but I am getting on average 12 mpg on LPG 50/50 city + motorway & I am not trying I just drive it.It sees 70 m.p.h all the time when on motorways
It does not do anymore m.p.g. on petrol which is 5.90€ & LPG 2.95€ a gallon.
Kevin
PS check your leads are 10mm,I get my ones made in UK from Mr Plug leads 80£,you can do it yourself for a lot less
Kevin
Thanks Kevin - interesting on the ignition side and the leads. I hadn't considered this.

I was also wondering about the plugs because it seemed to get through them very fast when running on LPG - which was expensive because the Hemi has 16 of them. I was wondering if there were up-rated plugs available.
 
#12 · (Edited)
To Shadow 11
I contacted my insurers who the classic & my Other car are insured with ( the same co) and explained I did 25000 per year and asked if they could change the limit as I was going to drive this distance anyway so they accepted and removed the restriction,last year I did 25,000 in the classic & 3000 in the Mercedes.My son tried to do this but the classic was in a different co & they would not do it .
I have 2 cars with FBD E220 CDI 2011 @ 650 € comp & business use & 84 Soirit 210€ both have brake down assistance & tow in & glass cover & no claims step back & open drive for 25 to 71.
 
#14 ·
I use Iridium plugs & got 20,000 miles on a set in my Bentley eight.
Another Tip For Lpd,
If your car has not got an oil lube unit to add oil to the valves etc. I use 2 Stroke oil added to my petrol,(100 to 1) and drive on petrol for a mile & finish up by driving 1 mile on petrol.
Leads. I always change my leads for 10mm ion every petrol car I buy they start better in damp/wet.
cleaner burn & in turn more mpg
With your Hemi you would be better buying a roll of 10 mm & making your own leads
A lot on the Forum will not agree with Iridium plugs & changing from stock leads or LPG but all of this turns the car into a very reliable day driver. I have almost 40,000 done over a few years & never failed to precede .
Kevin
 
#15 ·
Hi Kevin, another stipulation by my classic car insurer is that I must also have an ordinary car insured as my daily driver at the same time, not necessarily with the same insurance company but I must be able to show that I have another vehicle insured as my main mode of transport. Most years I'm not asked to state the current mileage at the time of classic insurance renewal but occasionally they do ask. I'll try FBD when my next renewal is due, Regards, Larry.
 
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