I've got a bit of a soft spot for diesels in small cars, and got to thinking. What makes a good diesel engine?

* Cast iron block, to survive high diesel compression
* Long stroke for lots of torque
* Two valves per cylinder, again for torque
* Forged pistons, conrods, crank
* Probably other things I've not considered

Mad thought: the 1098 A-series seems to fit the bill pretty well. It's well undersquare, strong, generally underrated. Why couldn't it be converted to diesel?

* Remove the spark plugs and you've got 4 convenient ports for injectors.
* Bolt on a turbo
* Install a fuel pump, common rail and injectors from a small European diesel
* The engine management system from any modern 4-cyl diesel should be adaptable
* The old 5-port cylinder head is no longer an impediment to engine management, since the intake ports suck fresh air only with direct injection.

The only thing I can think of which would be troublesome would be the compression ratio. Would a smallbore cylinder head be able to cope with diesel-level compression ratios? I assume the pistons in a diesel need extra compression rings?

Now I know BMC did a diesel A-series way back when, it was fitted to a Leyland tractor. Why couldn't a Mini engine be converted?

Discuss.

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Simon

The adventures of an owner builder in the Tallarook Ranges

Waste of time IMO, if starting with an A series block and a 3 bearing crank.
The 948cc BMC diesel made a whole 16HP at crank...
C/R was 23.6:1.
Head was totally different, with indirect injection.
I'd say just add a turbo and you'd blow it (up).

Conrods in this thing were heaps stronger than 1098 ones. in the pics they look much like S rods.

More info here-
http://www.austinmemories.com/page44/page44.html (scroll down)

Here's the link to the workshop manual...
http://www.instruction-manuals.co.uk/ca ... CminiT.htm

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I'd love to see a tractor head on an 850...

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did I tell you that I won a trophy?

I think turning an a type into a diesel with modern injection systems could be quite interesting. Most modern diesels run much lower compression then they used to i think its around 17-18 to 1 cr these days.with the much finer control of injection more power and better economy should be had then the 16hp of the old 948cc diesel.

That's what I was thinking. I wouldn't expect big HP numbers anyway, it wouldn't get a rev. It should make impressive torque though, especially with a couple of pounds of boost.. and that's what you feel on the road in any case.

So Doc, you reckon 1098 rods wouldn't be up to the job? How do you think the crank would cope?

I've been thinking I'd like to do something a bit different with the engine in the van.. I think a diesel A-series would fit the bill

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Simon

The adventures of an owner builder in the Tallarook Ranges

What did BMC do differently with the head they put on the tractor?

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Simon

The adventures of an owner builder in the Tallarook Ranges

im sorry i have nothing constructive to add about diseasels

a bmc mini tractor would be great tho

The major disadvantage would be fuel economy. It would be so great you'd forget where to fill it up...

I reckon you got that one right

Ever since I saw a Morry Minor converted to diesel with the tractor head (and turbo) I wanted to do a Mini.

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OK, so what's special about this tractor head?

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Simon

The adventures of an owner builder in the Tallarook Ranges

either find an old a series diesel or the bigger, much more powerful b series...

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Here am I sitting in my tin can far above the Moon
Planet Earth is blue and there's nothing I can do...



“A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.” - Jeremy Clarkson

Now where would be the fun in that!?

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Simon

The adventures of an owner builder in the Tallarook Ranges

found 'em

it was the whole tractor motor (note the big housing under the manifolds) - runs on biodiesel (not that it makes any difference), the whole of the underside of the rear is the fuel tank, apparently gets 5000k's or something silly on one fill. No power whatsoever, but who cares

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did I tell you that I won a trophy?

Looks factory original, apart from the turbo and garden hose.

I could just imagine being stuck behind that thing going up a long hill, as it belched black smoke that smells like a fish'n'chip shop fire.

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Too many cars, and too little time.