The Ultimate Classic GT/Sports Car

[ChimpOnGas]

Seven happy years of Chimaera ownership and I'm just back from my 11th continental trip, what a fantastic classic British GT this car is.



Average LPG fuel consumption 22.13mpg

Compare this with 24.21mpg in the same car on a very similar trip in 2011, driven in exactly the same way but sucking petrol administered by the 14CUX ECU & ignited by a distributor.

That's a chemistry defying 8.5% economy drop on gas vs petrol, by rights this shouldn't even be possible when you consider LPG in it's gaseous state has an energy density 24.7% lower per volume unit than petrol (LPG is 0.58 kg/L vs Petrol at 0.77 kg/L), a 20% economy drop is thought of as best in class in the LPG world, so my -8.5% is something I'm especially proud of.

Of course the car is more efficient on petrol now its running the Canems system, at a 26.10mpg average its actually 8% more efficient that it was on the 14CUX, a figure which may be of interest to anyone considering ditching their Lucas ECU & distributor for an after market ECU.

If I compare the car burning petrol on the Canems system with it burning LPG on the Canems system I'm actually losing 15% economy which is still a clear 5% better than all other gaseous LPG systems available on any car, a direct result of the unique stand alone LPG fuel and ignition mapping feature offered by the Canems dual fuel system.

So what can your really expect if you convert your 14CUX equipped 4.0 litre Chimaera to the Canems dual fuel system?

• Average 14CUX petrol economy = 24.21mpg

• Average Canems LPG economy = 22.13mpg

• Average Canems LPG petrol cost equivalent economy = 42.75mpg

In simple terms that's taking a 20 year old V8 TVR that on average delivered 24.21mpg, and turning it into one that (in cost terms) delivers 42.75mpg AVERAGE FUEL ECONOMY - ALWAYS!!

So on average and based on real world proven figures the Canems Dual Fuel system turns your thirsty Chimaera into a car that's as cheap to fuel as a Nissan Micra...

http://www.honestjohn.co.uk/realmpg/nissan/micra-k...

Edited by ChimpOnGas on Monday 22 August 21:54

[ChimpOnGas]

pjac67 said:

Nice one Dave - even better if LPG is 45% of petrol price (i pay 47.9 v 105.9p for petrol) making it closer to the magical 50 mpg...my 2500 and 3000m trips to Europe in the last year have saved me c. £750 in fuel (or would have done if I had not used a low loader to return on the first trip...).Man maths rules!

That's a nice equation, as I've said all along you've got to divide the forecourt petrol price by the LPG price at the same station to get your multiplier, then and only then can you times it by your true LPG economy to get the genuine petrol cost equivalent.

In the UK I've hit and exceeded that magic 50mpg cost equivalent figure many times even using my super honest real world calculation system, but the truth is to be fair you've got to take the average of the average over many fills... and the average multiplier on this trip was 1.933 applied to my average LPG fuel consumption of 22.13mpg.

So that's 22.13mpg X 1.933 = 42.77 cost equivalent which was carefully and accurately calculated over many fills at different stations throughout the trip, some gave me a better result and some inevitably were worse, its the average that really counts.

I avoid motorway service stations, not just because they are expensive, but because the price gap between their LPG & petrol is almost always inferior to the supermarkets like "Super U" & "E.Leclerc" who always offer cheaper fuel prices across the board anyway.

My best buy on this trip was 0.61 Euro per litre vs a petrol price of 1.27 Euro, so that's 1.27/0.61 = 2.08 X a good motorway run at 23.14mpg = 48.17mpg

Of course just down the road on the motorway the petrol was being sold for 1.38 Euro, so if I choose to compare my 0.61 Euro supermarket LPG price with that it ends up looking like this... 1.38/0.61 = 2.26 X 23.14mpg = 52.34mpg.

But to be fair it was never really 52.34mpg because you've got to say... "If I was filling up at this station today with petrol instead of LPG what would I be paying?" and then make your calculations from there. You've got to do brim to brim fills to accurately determine your true consumption and then you've got to do the same exercise many many times over an extended period so you can get to your true AVERAGE cost equivalent figure.

Then and only then can you be 100% sure you're not cheating yourself with man maths

My final point would be... Even if the economy figures you end up with are good, there's no point in going LPG if the car runs like a bag of nails, thankfully my Chimaera now runs significantly better on LPG than it ever did on petrol when the fuelling & ignition were under the control of the Lucas 14CUX and distributor.

Smoother - Faster - Nicer to drive... and almost half the cost to fuel

[ChimpOnGas]

ClassiChimi said:

I've been trying to find some words,,
Victory must taste sweet.

Off the wall madness proved to be a huge fking great asset that's saving tonnes of money over the years,,,,, as long as you do many miles,,, how many Euro trips was that 9 ,, well that's those miles right there, don't forget it still runs on petrol,

I've had an LPG jag V8 on LPG, nothing but praise for it to be honest, and it only piggy backed the Ecu so as Daves car is running the brilliant Canams system, is engines in safe hands.
Have you had any high temps abroad Dave, just wondering if the higher temp flash point effects the top end much, my Jag never ran hot though

Nice one Alun, and yes it got hot mate.

We suffered nose to tail stop start crawling for one hour in a massive holiday traffic jam into Arcachon, the ambient temperature hit a mind melting 37 degrees C, that's a mental 98.6 degrees fahrenheit!!!!

I know this because there was huge LED bill board temperature thing on the side of the road showing 37c (just visible in the photo below, if not readable) and the news that evening confirmed the same figure of 37 degrees C.

My rad fan one was running continuously as was my Davies Craig electric booster pump that's wired into the same otter switch controlled circuit, fan two which is separately controlled by the Canems ECU was cycling on and off every minute or so. This ECU controlled fan is set to come on at 93 degrees and go off at 88 so I know even without getting the laptop out my coolant temps were nailed at or very close to a genuine 90 degrees.

Basically no issues at all even though my resistor corrected temp gauge showed 93 degrees (now pretty accurate for a TVR gauge) and my vaporiser LED had turned from green to red indicating the gas system was rather on the warm side, but she still idled and ran sweet as a nut and even demonstrated she can instantly hot start on LPG at these temps no problem at all as I chose to give the engine a rest when we failed to move for longer than a couple of minutes.

Against all the odds and in stupidly punishing temperatures 'Ol Gasbag' proved herself to be completely bulletproof reliable

[ChimpOnGas]

Danattheopticians said:

Based on todays UK fuel costs, would you know even how far you'd have to have driven just to pay off the cost of doing the conversion?

The conversion should be seen in two parts:

1: The replacement of the Lucas 14CUX injection system and distributor ignition with the Canems system

This is pretty much the same cost as any other petrol only after market ECU (Emerald, DTA, MBE, Omex ect ect), if you're considering enjoying the benefits of a Canems petrol only ECU you'll only be paying an additional £200 for the Dual Fuel feature.

To this you'll need to add LPG tanks, injectors, pipe work, filter, filler point, and have a small auxiliary petrol tank made. But all that isn't as expensive as it sounds, LPG components are very reasonably priced so with extra £200 you'll pay for the dual fuel ECU you're looking at about £1,100 in parts plus fitting.

The way I did was to invest the extra £200 ECU money up front and just run the car on petrol for a year or so, essentially it really wasn't any more than the quotes I got for fitting an Omex or Emerald system which at the time were a little more expensive than the Canems Dual Fuel ECU including loom, fitting and mapping.

With a year of happy Canems petrol motoring where the benefits included a far smoother drive and improved petrol economy I then set about activating the LPG element of the Dual Fuel ECU and fitting the hardware to supply the engine with gas. Doing things this way spread the cost and separating out the petrol improvements I would have done anyway from the LPG conversion helped make the conversion a financially viable project.

If you follow my approach you might end up throwing a couple of grand at the LPG conversion element, with savings in the order of £0.08p a mile you've still got to cover 25,000 miles to break even, for me this happy day will come next June.

Danattheopticians said:

Also how far can you travel on a tank of LPG?

Depends very much on how the car is driven, but essentially the conversion was designed be a "Zero Compromise" installation, by that I mean the car should travel the same distance on LPG as it did when it left Bristol Avenue in 1996 running on petrol. My LPG range varies from 260 miles when I'm driving in a sporting manner to 322 miles on a motorway cruise as I proved on my last tour of France, on average I tend to enjoy a very practical 300 miles range on one 64 litre LPG fill with no risk of coming close to running out. Of course if I do run out I just flick to petrol where I have an additional 150 miles of range but I really cant remember the last time I needed to flick to petrol for any other reason than to run a bit of fuel through the petrol injectors whicjh I tend to do once a month to protect against any injector gumming or stale petrol issues.

Danattheopticians said:

Is LPG going to become more readily available?

Well, it's certainly a greener option and may well become a stop gap option while battery technology improves EV range to where it's practical, it's also a great way to "green up" older cars, but it's still a niche market fuel. Saying that I have no issues with availability, just download the LPG locations to your sat nave and use the various LPG apps available for your smart phone and you'll never have an issue all over Europe including the UK.

Danattheopticians said:

How much room in the boot does the tank take up? Is stowing the targa roof a problem?

Probably best to look at my post here:

http://www.pistonheads.com/gassing/topic.asp?t=125...

Everything is covered in more detail there, but to quickly answer your question I designed the conversion so the hard panel fits in the boot just like it does in the standard petrol only car and there is still sufficient space left for two people to tour Europe for two weeks without wanting for luggage space. Essentially I've hardly lost any luggage space at all, I have subsequently purchased a folding Surrey top but the advantage is the exactly same as it would be with the standard petrol car, its just a nice to have convenience and certainly not a necessity of the conversion.

Hope this helps answers your questions?

What is often overlooked is how the car runs on LPG, and on this point I'm please to report my Chimaera is infinitely smoother, more refined and easier drive than it was on petrol when running the old Lucas system. Its also faster with better throttle response with a good slug more torque that it ever had from new and that's with no cylinder head work whatsoever.

I designed it to be a no compromise conversion, and ended up with just that, in fact forget the huge economy advantage it's a better car than it ever was on petrol running a distributor and the 14CUX fuel only ECU.

Win, win, win

[ChimpOnGas]

MisterT said:

Unless it's changed in recent years Spain doesn't have much in the way of lpg provision. A few years ago we toured Spain travelling from Andorra via Madrid to Granada and then back up the med coast in the old Range Rover. Didn't find one lpg station! The saving grace was petrol at iirc about 65 cents/litre when petrol at home was about £1/litre. Back into France and there was lpg at every filling station but the petrol price in France was closer to the UK price.

I guess the lower petrol price in Spain made the case for lpg less attractive. Of course it's some years since, and things in Spain may have changed?

The numbers on the map below relate to the number of stations in that area.



I haven't toured Spain in my TVR but it doesn't look to me like it'll be a problem, more detail in the link below where you can zoom in on the map...

http://www.mylpg.eu/stations/spain/map