engine blocks

[jim.quackenbush]

hi all---I may need some help here as I have no access to or know where to find the info I need---or the patience to find out---basically I have bought an MG midget standard A series 1275 "thick flange" block/Healey Sprite 1300 BMC---
So questions are:-
What front and back plates are suitable and any part numbers (as it looks like there are a few different types)
Also crankshafts applicable and in particular the camshafts that can be used
As I intend to have the unit re-bored are any suggestions on the piston and ring sizes ie +020/030/060
Also I have a re conned 12G940 head with the exhaust valve seats machined 080 deeper and a rocker assembly from an MG Metro
As I intend to use an HIF44 carb with heated manifold---(can anyone tell me why the inlet manifold needs to be heated)
So can a Ford T9 box be fitted---(already purchased a reconned item from 1st motion trans.)
Lastly---what does "thick flange" mean

My car is a 1967 2 dr in black---it is a basket case---rear end damage from a shunt and severe rust from wheel arches down---about 40 or so photos so far
Work done;-
renew and realign rear chassis members---new inner wings---new outer wings---new front and rear floors---new inner step sills/boxing plates and extensions/new inner rear sills---new inner front sills---new flitch panels---new door hinge panels---recovered doors---new boot lid---so still a lot to do
Any help with the above items i'd be very greatful
Jim

9can

[philthehill]

The MG Midget 1275cc rear engine plate is the plate to use Pt No: AEG552 (MOSS). You must use the correct oil pump cover.
You can get a modified rear engine plate to suit from ESM or other Morris/MG parts suppliers.
The Morris Minor front engine plate is suitable but the 1275cc Midget front engine plate Pt No: 12G1309 (MOSS) has an additional strengthening plate but it is not essential that the front plate has it
The 'A' Series camshafts are all interchangeable but the oil pump must suit the camshaft drive i.e. pin drive, star drive or slot drive.
The piston will be relative to the bore size after measuring the bore wear and the re-bore size to return the bores to good condition.
A Ford T 9 gearbox can be fitted with the correct fitting kit.
Thick - thin flange means the thickness of the flange at the bottom of the block and onto which the sump is attached.
The thin flange is 6mm - 8mm thick. The thick flange is 14mm - 15mm thick.
The thickness of the flange has no relevance to a normal road car. The competition boys/girls like to use the thick flange block as it has more strength along the bottom of the block.
The 1275cc Midget has different conrods and big end journals to the 1275cc Marina/Ital and the crankshafts and conrods can only be changed as complete crank/rod sets.
The inlet manifold does not have to be heated but a non heated inlet manifold is more likely to suffer from icing of the fuel.
All 940 heads can be fitted as standard to the 1275cc block but be aware that not all 940 heads are the same in all aspects.

[jim.quackenbush]

Hi---left a PM for you---can you tell me if a marina crankshaft (12G1303 EN16T) will fit this block---as I just read your reply post about the crank differences with the midget one---I think I have read it right that this crank should have facility for a spigot bearing to accept the T9 box and has larger 1.75" journals but it should fit this block
jim

[philthehill]

Received, read and replied to your PM.
The 1275cc Marina/Ital crankshaft will fit without modification into the 1275cc Midget block but you have to use the 1275cc Marina/Ital con rods as the big end bearings are larger (1.75") to take into account the lesser grade steel used in the production of the Marina/Ital crankshaft.
The Marina/Ital and 1275cc Midget main bearings are all the same at 2".

The Marina/Ital has either a plain Oilite (trade name of the material it is made from) spigot bush or a needle spigot bush in the rear of the crankshaft.

Have a read of these links:-

https://www.frontlinedevelopments.com/w ... remote.pdf

https://www.frontlinedevelopments.com/p ... arter-kit/

Below - the rear end of a Marina/Ital 1275cc crankshaft.
Note the one flywheel location dowel. The 1275cc Midget crankshaft has two flywheel location dowels and a register to hold it all in place.