Mini with economy, coming from a different angle
Mini with economy, coming from a different angle
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Discussion

Skyedriver

Original Poster:

21,947 posts

303 months

Friday 18th April 2008
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My mind started wandering whilst watching "Peppa Pig" on TV with my 2 year old laddie...
Friends Citroen 2CV, known for it's frugality, passed the window and I started to wonder about the practicallities of building a mini for economy rather than out and out performance.
The old minis I have had in the past managed 40mpg, the 850 a little more. The Metros about 42mpg, the MG about 40 and the turbo about 35.
Has anyone ever managed a build to get 50+mpg, the K series Rover 414 we had did over 40 so surely a 1.4 in a mini should be better.
That of course had 14" wheels,
A mini could be stripped down to reduce weight, perspex glass, f/g boot and bonnet etc
Surely in this day and age we should be able to get 50+

GreaseNipple

472 posts

262 months

Saturday 19th April 2008
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I used to get 48 mpg out of my 998 pretty easily so it cant be too hard.

Skyedriver

Original Poster:

21,947 posts

303 months

Saturday 19th April 2008
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Guess the old Cast Iron lump will be a prob., something modern and light....
Can't imagine how you got 48mpg, never managed anything like that.

rougeleo

213 posts

259 months

Saturday 19th April 2008
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Diesel ??

bob1179

14,126 posts

230 months

Saturday 19th April 2008
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You could use a 1.1 K Series instead of the 1.4? (As used in the Rover 200/25)

They are still pretty pokey and should be cheap to buy.

smile

Skyedriver

Original Poster:

21,947 posts

303 months

Saturday 19th April 2008
quotequote all
rougeleo said:
Diesel ??
yes was wondering if there was a small diesel engine that would work.

This is just a worm wriggling it's way through my mind at the moment you understand, nothing definite. Just with fuel costs the way they are going, a pre '73 mini doing 60mpg must be a useful little everyday vehicle.

The 1.1 in a Metro? is that a K series or a 1098 A series engine?

Some of the other far eastern small cars seem to give good mpg, anything there?

guru_1071

2,768 posts

255 months

Saturday 19th April 2008
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my race mini manages 10mpg...........


getmecoat

Huwbertus

59 posts

262 months

Sunday 20th April 2008
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what about the 3 cylinder diesel from an Audi A2?

bob1179

14,126 posts

230 months

Sunday 20th April 2008
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Skyedriver said:
The 1.1 in a Metro? is that a K series or a 1098 A series engine?

Some of the other far eastern small cars seem to give good mpg, anything there?
Originally the Metro came with the 'A+' engine, then when it was revised in the early 90's they fitted the 'K' Series, which also included a 1.1 litre variant, they also used that engine in the later Rover 200, being a 'K' Series it is pretty pokey and returns good economy. Might be worth a look.
I'm not sure how easily a 'K' Series engine will fit into a Mini though, as I'm not as to whether you will be able to drop one in or require a new front subframe due to the gearbox and ancilliaries etc.

smile

DanGT

753 posts

247 months

Sunday 20th April 2008
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David Visard book has a lot of info on economy if I remember correctly he got 65-70mpg?

Skyedriver

Original Poster:

21,947 posts

303 months

Sunday 20th April 2008
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bob1179 said:

I'm not sure how easily a 'K' Series engine will fit into a Mini though, as I'm not as to whether you will be able to drop one in or require a new front subframe due to the gearbox and ancilliaries etc.

smile
conversion uses a modified Metro subframe and loses a lot of the minis handling and roadholding, however if you can get used to that.....

Skyedriver

Original Poster:

21,947 posts

303 months

Sunday 20th April 2008
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DanGT said:
David Visard got 65-70mpg?
WOW! now you're talking, how did he manage that?

bob1179

14,126 posts

230 months

Monday 21st April 2008
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Skyedriver said:
bob1179 said:

I'm not sure how easily a 'K' Series engine will fit into a Mini though, as I'm not as to whether you will be able to drop one in or require a new front subframe due to the gearbox and ancilliaries etc.

smile
conversion uses a modified Metro subframe and loses a lot of the minis handling and roadholding, however if you can get used to that.....
That's the one thing I'm not sure I'd be able to sacrifice in a Mini, it's handling! I love the fact they are like go karts.

Maybe you would be better of sticking with an A or A+ Series engine? Looking at the bigger picture, they still give great economy, are reliable andm you get to keep fun handling.

smile

FWDRacer

3,565 posts

245 months

Monday 21st April 2008
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guru_1071 said:
my race mini manages 10mpg...........


getmecoat
Mine managed 8mpg at Spa...

getmecoatgetmecoat

DanGT

753 posts

247 months

Monday 21st April 2008
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Skyedriver said:
DanGT said:
David Visard got 65-70mpg?
WOW! now you're talking, how did he manage that?
A lot of the work was the same as you would for power, but for the head you would improve the flow but not increase the size of the valves. I have not looked at the book for over a year. I will look tonight and see if I can give you a bit more info and check the mpg he got. Dan

Mr2Mike

20,143 posts

276 months

Monday 21st April 2008
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With a properly mapped fuel injection system it should be possible to improve on the old carbed engines. Trouble is the modern EFI minis are quite a bit heavier than the older one which negates a lot of the advantage (as well as all being 1275's rather than 998's or 848's).

The SPI throttle body and manifold might be a good start for a small bore, coupled with an aftermarket EFI system though I suspect the manifold bore will be too large for optimal economy. The MPI system is to too complex on a mini (w.r.t. injector timing constraints), and isn't well supported by aftermarket ECUs AFAIK.

Phil Hill

433 posts

297 months

Monday 21st April 2008
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Skyedriver said:
DanGT said:
David Visard got 65-70mpg?
WOW! now you're talking, how did he manage that?
From memory there's details in the economy section of his "the big yellow book"; soft-ish cam, cleaned up head and combustion chambers (with lots of compression I think, which seems to go against modern thinking wrt crappy modern fuels), good exhaust, manifold and filters, heated inlet, spot-on ingition curves, keeping engine temp to 75 degs, tall gearing, narrow wheels........ I think alot of the same principles apply to performance modification, but with out going overboard with everything except the compression ratio..........

Bearing in mind that was acheived in the late 70's early 80's perhaps if you could build a completely optimised 998 or 1275 with a modern cam, good fuel and ignition control, optimum timing etc then you could get close or even better. Also paying attention to the wheel bearings (the reason "low rent metro's" had plain ball race bearings instead of Timken taper-rollers was to cut down rolling resistance !!), suspension geometry and dampers, all the basic service items that get neglected over time and sap your valuable mpg by turning fuel into heat.......... and shed alot of the "fat" modern mini's carry, back to basics !!

My old stage 1 998 mini with a 3.1 diff used to get 45 on a run and 35 in town with 165 tyres and a lead-foot...... My 1380 mini with a 3.4 diff it used to get 50 on a run and 38 in town with 175 tyres and a lead-foot......

but then I started to play with the 1380 and got that down to 30 on a run and 18 in town with a 3.6 diff, and better porting, and more cam, and 1.5 rockers........ you get the picture !!

Phil.




Cooperman

4,428 posts

271 months

Monday 21st April 2008
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My 1310 rally 'S' does about 12 mpg on stages and 20 mpg on the road.

rougeleo

213 posts

259 months

Monday 21st April 2008
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How about the engine out of a Toyota AYGO 1.4L Diesel

reliablity as well as economy

FWDRacer

3,565 posts

245 months

Tuesday 22nd April 2008
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rougeleo said:
How about the engine out of a Toyota AYGO 1.4L Diesel

reliablity as well as economy
How about washing your mouth out with some soap... hehe

Joking aside - I remember reading a Mini magazine from eons ago where a Daihatsu 3-pot turbo-diesel had been installed in a lightly modified front subframe complete with its end on 5-speed box. I think some hybrid driveshafts were required but it kept the standard mini hubs, geomtry and essentially fun. Which is what it is all about, isn't it? cloud9