Mini Engine swap

[kattweaver]

Im sure this has been endlessly covered on here but searching the word "mini" and "engine" is of course bringing up many non specific posts so i will just go ahead and ask.

We have been very kindly donated a very nice 1340 A series that was taken out of a mini and we want to use it in our traveller.
What gearbox and axle combination have people used in the past?
we have a very knowledgeable engineer in the family who agreed to help us make and mend but we would like to do as much as possible ourselves and we barely know what we are doing.

We are sensible on the roads and just want to be able to cruise comfortably at 70 so the strength of the axle is not the main issue.

Whats the sensible way to go about this.

Brief searching has led us to BMW 3 series box and reliant rialto rear axle...

Any thoughts?

[brucek]

The problem you have is that the mini is a front wheel drive car wheras the Minor is a rear wheel drive. Also, the mini engine is fitted across the front of the car (transversely) and has the gearbox directly below the crankshaft and engine. In the Minor the engine is fitted in line and the gearbox is fitted behind the engine linked to the propshaft which drives the rear wheels. Unless you are planning to convert the Traveller to front wheel drive ( which is a huge job and not an easy one by any means), the mini engine swap simply won't work.

[kattweaver]

So apart from the gearbox mounting problems what is the actual difference between the two engines and why cant it be adapted to work? apologies if the answer is obvious.

[bmcecosse]

It's not a 'gearbox mounting problem' - it's a very different arrangement altogether..... The block has some basic differences, and the crankshaft (and flywheel/clutch) is completely different... It's not impossible but just not a very practical proposition..... Your 'very knowledgeable engineer' will surely understand....... There is no 'sensible way' to do it.
The usual upgrades when using a more powerful (often Ford) engine are Sierra gearbox, and Escort or Capri rear axle.

[kattweaver]

Thank You for the input I'm sure we sound like complete novices unnecessarily biting off more than we can chew but we have been given the engine and would like to make it work if possible. A sort of challenge that has been set for us. Any advice will of course be appreciated along the way.

So if we were to think of this as an option what are the main factors to consider?

[philthehill]

It can be done but as Bmc says it is not an easy job.
The main points are:-
The rear main bearing cap is different but a suitable replacement is available from Peter May Engineering http://www.petermayenginering.co.uk/cat ... catalogue7 item part No: 7.583 @ £72.00 plus VAT. That replacement rear main cap would have to be line bored to ensure alignment of the rear bearing at a cost of approx £250+ plus VAT.
The crank is different and you would need to source and fit the 1275cc Midget crankshaft and flywheel at approx £400 + plus VAT. The last 1275cc Midget crank that I purchased cost me £400 and it took me 6 months to find it. Peter May Engineering may have those spares on the shelf but they will not be cheap. You will also need the oil pick up and sump. The sump these days is a rarity.
As you can see the cost are mounting up.
Instead of trying to use the Mini engine I would suggest that if you want to increase the engine capacity you purchase a 1275cc Midget engine (£400 -£700) and use what you can off the Mini engine. If you had the Midget engine bored to 1340cc (approx £84 plus VAT per bore) you could use the 1340cc Mini pistons/rods provided that they are in good condition. Instead of the Midget engine you could use a 1275cc Marina engine with modified engine back plate (Part No: 10M002 £42.95 Plus VAT) and modified flywheel (Part No: 10M001£48.50 plus VAT) both are available from ESM. That could be over bored if required.
Please note: All prices quoted are real prices taken off the web pages of reputable motor engineering companies and not just what I think they are!!

[bmcecosse]

It's not an option... You should sell the Mini engine and buy something suitable with the money! To use the Mini engine you would need to modify the block to take a Minor type oil pick-up, source a suitable (MG Midget) crankshaft + flywheel and clutch. Have a rear main bearing cap specially machined up from say EN24 steel - and line bored to the block and the other caps. And of course source a sump for the block. Also fit a Minor front plate - but that's easy. I would estimate at least £500 -very possibly more. It's just NOT WORTH IT ! Then you need to match it to a suitable gearbox - the Minor box won't last long - and the axle will break a half-shaft. So as above - you need to source a Ford (or Toyota - hard to find) gearbox and suitable bell-housing (£500/600) - and either fit hardened half shafts (£300) in the Minor axle or a Ford axle (maybe £100 if lucky) . And what about wheel/tyre , brakes and suspension upgrades before you add ANY extra power to your Traveller?? What spec is the Traveller at the moment??

[bmcecosse]

Your prices are even higher than my estimates Phil!!

[philthehill]

Bmc
I was very careful to do my research before posting prices. If you consider that those costs are high then you would hate to know how much my 1380cc engine cost me to build and that is without my labour taken into consideration.
As regards the Mini oil pick up - looking at the Mini wksp manual the pick up pipe entry/position/size into the block appears to be the same as the Midget so if you use the midget oil pick up pipe as I suggested it should pick up oil. Yes the auto Mini version is different so what would you have to do to use a MG midget/Minor oil pick up pipe on a non auto Mini block?
You are right about the transmission even my BMC ST SC/CR gearbox could not cope with the extra power and I had to fit a Quaife SC/CR box. The Minor back axle has put up with the abuse quite well (only one diff failure so far) but it has heat treated half shafts. I found that increasing the power just moves the transmission failure point further down the transmission line, you cure all the problems increase the power and it all starts again!!!

[bmcecosse]

No - I'm sure your prices are right Phil - I was assuming a secondhand crank/fly etc (not easy I know..) and making an 'educated guess' at the other costs, and frankly trying to make them as not-scary as possible. The oil pick up IS in the same place - but it's not threaded to take the pick-up pipe, so that would need to be done. I wasn't aware a rear bearing cap was available (is that with the labyrinth seal built in ??) and of course need to find (or machine up) a top section for the labyrinth too - but your line-boring costs are certainly scary....and the boring costs too...... Richard gets round the weak diff with a Limited slip - which promptly broke a half shaft, so the tough shafts really are essential if keeping the A series axle.

[philthehill]

Bmc
The machining costs nowadays are quite scary! For one example see http://www.oselli.com/service/engineering I know that they are at the top end for machining costs and you may be able to get the work done cheaper but I did say using a reputable motor engineering company. Thankfully I have a couple of spare modified 1275cc Midget blocks and modified cranks on the shelf if required but hopefully never will. Yes you are right in that the top part of the rear bearing cap which fits on the rear of the block would have to be obtained. Use could be made of a S/H part from a scrap engine and I know that they are a selective fit but I am sure that it could be made suitable with a little effort or alternativly fit the rear main seal kit (Pt No: 10M800A £65.00 plus VAT from ESM) which I am not a fan of; having been there with poor results even though correctly fitted.
1275cc Midget cranks on their own are quite rare and I had to travel from Hampshire to Warrington to find one. The £400 that I paid for the crank was for a S/H one but in very good condition. The problem with the Midget crank is that you can only regrind to -10thou, any more and you have to get it re-heat treated. That was only the start as I went on to get the crank cross drilled, wedged, re-heat treated and balanced both static and dynamic which pushed the final cost up.
Thanks for the pointer regarding the oil pick up pipe. I have just found a picture of a Mini oil pick up pipe in David Vazard's book 'How To Modify your Mini' and note that the pipe is secured to the block by two bolts/set screws. So you are right in that to fit a standard MG Midget/Minor oil pick up pipe the Mini block would have to be drilled and tapped to suit. Or alternatively you could use the block end of the Mini oil pick up pipe and braze it to a modified MG Midget/Minor oil pick up pipe.
Whilst it is possible to fit the Mini engine after a lot of effort and cost I have to agree with you in that it would be better to sell the Mini 1340cc engine and invest in a 1275cc Midget engine or Morris Marina 1275cc engine to save both the effort and the costs involved. Happy motoring.

[JOWETTJAVELIN]

From my experience of both 1100 and 1300 engines, in standard trim, there is really not much noticeable difference between the two apart from hill-climbing and pulling power. The acceleration is near as damn it the same, they both get bothered if trying to cruise over 65MPH, and 60 seems to be the speed they naturally sit happily at.

I have sometimes ran a 1300 at 85 MPH for at least 2 hours, but the engine rpm is much increased.

[bmcecosse]

The original poster, after being very confident they were right......fails to come back in any way after we have made enquiries/looked up parts prices / spent time researching etc etc and come to the same conclusion that it just isn't practical.... Oh dear - I'm not sure why I bother..........

[kennatt]

another on your list roy

[JOWETTJAVELIN]

Not all wasted. It is valuable information and makes food for thought.

Perhaps the OP will attempt this conversion anyway?

[kattweaver]

The original poster, after being very confident they were right......fails to come back in any way after we have made enquiries/looked up parts prices / spent time researching etc etc and come to the same conclusion that it just isn't practical.... Oh dear - I'm not sure why I bother..........

wow we really just opened a can of worms with this question didn't we? I have only just seen the responses (working 50-60hour weeks) and they are indeed appreciated. We certainly never were confident about anything, hence asking the most basic of questions. Im doing my research but from the most basic of places, i barely know what most of the things in the responses are regarding and excuse me if it takes some time to think about and reply.

I will discuss the pointers that you guys have kindly given with the the person we got the engine off and see if he still wants to help us go ahead with using it.

[brucek]

Katt - I think most of the experienced posters on here just want you to fully appreciate that, whilst it can be done - it's very much more expensive than searching for and purchasing a suitable in-line alternative. After all, free is only useful when you can use it without having to spend loads more altering your car. If you really want to explore engine options - and keep the car looking pretty much standard - you could do worse than get a copy of Tuning BL's A series Engine by Dave Vizard - a well known and respected guru of all things A series. For the sort of money you would have to shell out on making the mini engine fit, you could do some pretty impressive upgrades and modifications to your existing engine and save yourself a considerable amount of hassle. Alternatively you could buy a spare engine and have that modified whilst using your current one until your new one is ready . I guess also that some may not appreciate that folks do have to work some crazy hours these days just to get by (see some of the times that I post for example!!) Here's a link to the e bay pages with the Vizard book in case you want to browse.

http://www.ebay.co.uk/sch/i.html?_odkw= ... e&_sacat=0

Good luck

[bmcecosse]

Sell it!

[bmcecosse]

Here's a 1275 engine suitable for a Minor - gasp at the price - and it's far from 'new'.... http://www.ebay.co.uk/itm/231044381194? ... 1423.l2649

[kattweaver]

Thanks guys, advice taken, its not like we need a new engine but as it was a freebee and we do a tonne of fully laden motorway miles it was worth looking into how straight forward it could or couldn't be. If anyone is looking for a mini engine let me know!