Identifying Turbo Parts
Turbo Mini Forums

I’ve been offered a “turbo set-up” which came with my mates Mini Maguire, and was allegedly running in the car before he brought it. However the engine was not installed in the car when he got it, and there are a few bits missing. Now it’s been a few years since I last owned a Turbo lump (and that was stock) so I’m a bit rusty, and want to make sure everything is what it seems before I part with my cash.

My first concern is the block, whilst it seems in good condition with very smooth bores, there are a couple of areas I’m concerned about. Sadly the engine no is missing, so are there any other ways of identifying the block? The bores appear to be lined, is this normal on a turbo block? I didn’t think it was but I can’t remember. Also where you would expect to find a mechanical fuel pump on a normally aspirated A+ series, there’s a hole (& a suspicious looking bit of gasket), did the turbos have a blanking plate? Or were the blocks cast without a hole for a fuel pump (I know the A series engines used in MG Midgets are cast with out a hole, but that’s of no use).

My next concern is the pistons, is there any way of checking is these are correct (have the larger crown) without stripping the engine? (I am hopeless at fitting pistons) the pistons, which are fitted at the moment, are definitely dished, I don’t know the cc but that’s easy enough to measure with a syringe. How essential is the larger crown? I know at high boost levels you’ll melt holes in normal the pistons, but I’ve got no plans to go above 7 psi.

How do you tell if the Dizzy is the correct one as the turbos where either fitted with a 59DM4 or a 65DM4, the later also being fitted on normally aspirated engine but presumably with a different advance curve.

Finally if I have to strip the blooming thing, does anyone know the part numbers for the stock metro cam and the turbo oil pump?

Thanks in advance, and sorry if I posted it in the wrong section.

Rob

well the BLOCKS are all the same

starting from the head the turbo unit used sodium cooled exhaust valves which were slightly bigger on the stem diameter compared to the inlets

also the main bearing caps were of the plain bearing variety (ie) they used a bottom plain bearing for extra loading the tang to keep the shell in had been machined, broached in the CENTRE.

going back to the block where the fuel pump fitted this was the return oil feed for the turbo

the gearbox supported a larger first motion shaft support nose bearing, than the none turbo but this is not necessary as some guys on here runs the smaller bearing which is found on the none turbo box no problems

the diff ratio is 3.2:1 as the standard metro is 3.4:1

without dragging some books of the shelf and wading through these, this should be a enough info but i am sure my fellow mini turbo friends would add to this thread

nothing special really only the bottom shells & exhaust valves together with the blower and all the ancillaries not forgetting the inlet manifold which flows the best for the turbo

leyland got this spot on!

god bless em.

The block had the same fuel pump hole on the back as all A and A+ blocks as it was the oil return from the turbo.

Don't worry about the cam and oil pump as there junk and you'd replace them anyway.

There was talk on here about blocks having liners but i and alot of other havn't seen one personaly.

I think the stock pistons had an 11cc dish but could be wrong on this.

Oh and welcome to TM.. and just use the search function it brings up wonders of information.

Karl.

Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

Thanks guys,

I’d totally forgot about the oil return, although I remember learning about the big end shells the hard way (I didn’t realise that they where fitted to later normally aspirated blocks as well, and brought the wrong ones a few years back).

I’m not too worry about the box being genuine, I’ve never heard of boxes suffer from having a smaller first motion bearing, normally the diff pin is the weakest link. (now regretting selling the cross pin) Also I’m pretty happy when it comes to the head, as these are easy to identify by the valve sizes.

Despite searching I’ve haven’t found any way of checking the dizzy is a turbo item, any ideas? And is there anyway to identify the pistons without stripping the engine down? Even with a low boost (7psi) I don’t think normally aspirated pistons would last too long.

Cheers

you should be able to check th dizzy,it has a number on the vacuum pot and one on the baseplate that tell you the advance of each

Metro turbo weekend driver,Mini turbo in the making again!

Not that I'm an expert by any means either as this is my first foray into turbo A Series and we never got them originally in australia, plus I'm a Midget man not Mini, but....

I was reading Vizard to build information the other night and he states that linered A+ blocks were 1982 vintage as teh factory had boring problems and instead of scrappign them all had them lined. Aparently fine and will take +.2 or .4 overbore but that's it and supposedly not good for full race engines.

Gavin