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MG Midget and Sprite Technical - 1275 block

Hello,
I have to rebuilt a 948cc engine but the cylinders need a rebore to 1015 cc minimum with new pistons and conrods.

For this block I have a rebuilt stage 3 unleaded head (12G202 ported and with 1275 valves). It is obviously a 9 studs casing.

I have the opportunity to buy a new 1275 block (see photo). It is certainly for a Marina, and certainly a 11 studs.
Sure this block with crank and pistons is cheaper than rebuilding my 948, and is larger.

BUT:
Is it possible to fit the 12G202 on this block?
Is it a nonsense to fit my head on this block?

laurent




ld derancourt

another photo

ld derancourt

The block is NOT a Marina block but Ital which is A+. So you'll need an A+ distributor, use an alternator not dynamo,etc.

Why not buy a new book first??

Daniel Thirteen-Twelve

And to add yes you can fit the 12G202 head but that will reduce the power a lot!

just get a 12G940 head (std 1275 casting) dan you will be fine.
I have one with big valves and verry smal chambers spare (high CR not for a std road engine) if you are intrested....

You can use all of you A stuff exept for the distributor and dynamo.
but since the mini's had the A+ from the early 80's they are lots of them around.

Buy the engine
Buy Daniels book
read
fit a fast head and cam and have fun!
Onno Könemann

Daniel,
Do you have an offer to upgrade First Edition in Third Edition (LOL)?

For the distributor, I have to change the one I have got, because the casing is broken.

So the best way is to buy it, to buy a 12G940 head, a new distributor and a new exhaust manifold (different from the 948cc).

For this block, I have a MG Metro atmo camshaft, a belt drive conversion and a Rivergate adapator rear plate and the flywheel with clutch for the Datsun 5 speed box.

laurent
ld derancourt

A+ distributor, looks like you need the fork to fasten it with (A+). The flywheel will need modifying for the Ital crank - though I'm not certain without checking. Couple of other small things you need to note when you use the Ital block...
Daniel Thirteen-Twelve

You are correct
And do it right the first time!
Buy an 123 ignition get a mild modified head i would get a slightly wilder camshaft (minisport evo 1, piper 270, kent 276 etc) as the MG metro one is a bit tame (nice for a 948/1098)

Minispares is the cheapest/easyest for all the small A+ things (like the distributor fork)
Onno Könemann

This thread was discussed between 10/08/2010 and 11/08/2010

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