38 Mpg from a 260 Horse Power TVR Chimaera

[ChimpOnGas]

Today I achieved the cost equivalent of 38 Mpg from my 260hp 4.0 litre V8 Chimaera.

Making this TVR as economical as an every day four cylinder petrol hack.

How?

See here

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[ackbullchang]

Well done Dave , it was good to meet you and Frenchie at the Neil Garner open day. I was with Phil in the Arancio Orange turbo chim.

Out of interest, of course if you are prepared to divulge costs, how many years before payback of your initial outlay over a standard car returning 1/2 of your mpg i.e. 19mpg? Also, was this with the final tweaked map, or running on the base map?
Cheers
Chris

Edited by ackbullchang on Wednesday 3rd April 23:19

Edited by ackbullchang on Wednesday 3rd April 23:21

Edited by ackbullchang on Wednesday 3rd April 23:21

[scotty_d]

Been following this for a while really pleased it worked out. I think LPG is great stuff ran it for years my self and my father has the for last 12 years. No idea why so many are negative, more than likely they know little about it so make judgements on a small amount of knowledge. Good on you many cheap miles ahead of you now

[gordonsalive]

Sounds OK, but I had a 4.3 chim which returned around 30mpg on a decent run (of course using the loud pedal more vigorously could reduce it somewhat)

[BIGMIKE1]

Looks a really nice conversion, is this 38mpg around town or on a run then? As already mentioned above I was thinking it would be better than that as my standard 4 litre does 30mpg on a run so with full new modern engine managment system I would hope the mpg on petrol would be better than my 30mpg. Or is there more still to come with extra mapping etc?
Hats off to you anyway looks very factory fit but a bet it cost a few quid!
Mike

[scotty_d]

Here is his chart below LPG is around half the price of petrol so you can double the mpg figure of petrol more or less when running on gas.

ChimpOnGas said:

A picture of the fuel economy & range is starting to take shape.

The map to get the car to the Neil Garner was on the safe/rich side, given the constraints of time it worked extremely well, the car drove great but the fuel economy needed some work.

That map has been substantially changed over the last two days, the objective was to keep the drivability but improve the LPG consumption.

Today the car gave 21mpg on LPG, this represents a 15% higher consumption than petrol on a like for like drive.

It's well accepted that you lose something between 15-20% fuel economy when running on LPG due to it's lower calorific value, so a 15% loss is actually very good.

However, when you crunch the numbers my 21mpg is actually the cost equivalent of just over 38mpg

The two tanks hold a total of 52 litres of LPG so at 21mpg we have a range of over 243 miles on LPG with an addition 200 miles available from the 8 gallon petrol tank if I need it.

I'm confident when touring where more motorway miles are covered, the economy will improve further.

With this type of driving my Chimaera easily delivers 28mpg on petrol, so following the 15% loss figure that should give me the cost equivalent of 43mpg & a 273 mile range on one of my long continental tours.

Here's the figures in detail:



Right, I'm off to Belgium early tomorrow morning for a proper 600 mile round trip test

Edited by ChimpOnGas on Wednesday 3rd April 21:57

[Byker28i]

Ah yours was the one with the two lpg tanks and a purpose built petrol tank on top? Very nice job and still lots of room in the boot.