10 replies to this topic

[Yams]

Just wanted to get the low-down on the specs of the 1300 gt engine. I'm very confused.

 

Some are saying the 11 stud head was standard, but mine hasn't had the machining for the 11stud head, it was bolted down with 9.

 

 

The pistons seem to be fairly heavily dished. I thought standard A series pistons were flat top?

The picture doesn't do it justice, I'll have to crank it round with pistons at the top of the block to show fully, but here it is for now.

 

 

It also has a magic wand gearbox, i want to replace it with the 'standard' shifter that comes up by the front seats. Would a standard 1275 gearbox whack straight on?

 

Yams

 

[mini13]

I'm pretty sure the 1300gt had dished pistons,

 

1300gt's had...

 

35mm inlet valves ( and stainless valves)

11 stud heads (and blocks)

innocenti style conrods (  have a small ridge halfway up the rod beam

remote box wit.h the ally extension with a ribber sandwich plate between the box and extension.

[Yams]

I'm pretty sure the 1300gt had dished pistons,

 

1300gt's had...

 

35mm inlet valves ( and stainless valves)

11 stud heads (and blocks)

innocenti style conrods (  have a small ridge halfway up the rod beam

remote box wit.h the ally extension with a ribber sandwich plate between the box and extension.

 

The problem i have is the engine block is that from a 1300gt, but it hasn't been machined for the 11 studs. This is what has confused me. Was that normal?

[mini13]

not as far as I have seen.

[Pigeonto]

Just to throw a spanner in the works. theres a lovely 1300GT round this way. It's at all the shows and I often look at it. He says it's totally original and it has 9 studs. So it's possible there were actually some with only 9 studs.

[Cooperman]

The original MG1300GT had a 9-stud block. It would have had dished pistons.

However, a 'magic wand' gearbox is very unusual with any 1300 engine as they were mainly only fitted to the 850. if it is an early 'magic wand' gearbox the bearings may not be up to the torque of the 1300 engine, so it's worth checking with 'guessworks' on here.

[carbon]

Yams - do you still have the engine ID plate on the top front of the block? This will help to confirm the motor type you have. Also if you still have the original 25D distributor fitted then the lucas part number will give a further pointer.

 

The dish in the 1300GT pistons was the same as the Cooper S, they run the same CR.

[Yams]

Yams - do you still have the engine ID plate on the top front of the block? This will help to confirm the motor type you have. Also if you still have the original 25D distributor fitted then the lucas part number will give a further pointer.

 

The dish in the 1300GT pistons was the same as the Cooper S, they run the same CR.

 

The engine ID plate was slightly damaged. However with help to some other users here i think i have the full number. 12H5AA-H4480, or at least thats as much as i can get. I don't have the distributor or anything. I have head, block and

gearbox number too.

 

Head: 12 g 940

Block: 12 g 1279

Gear box: 22 g 1128

[carbon]

If you have got the gearbox split from the block have a check inside, 1300GT gearbox should have the laygear stamped 1040, this has the slightly closer ratio - less of a step between 3rd and 4th gear.

 

These gears can be used in the later 'rod change' box, but make sure you give this to someone who knows what they are doing with mini gearboxes.

[nzmember]

It might be 12H SA H4480 which is the code for an Austin 1300GT with close ratio gearbox.  Maybe the second A is a / or - between the codes?

 

http://www.ado16.inf...ngine_nos.shtml

[Yams]

If you have got the gearbox split from the block have a check inside, 1300GT gearbox should have the laygear stamped 1040, this has the slightly closer ratio - less of a step between 3rd and 4th gear.

 

These gears can be used in the later 'rod change' box, but make sure you give this to someone who knows what they are doing with mini gearboxes.

 

Yet to split it all up, just the head is off at the moment. Soon as i the whole engine stripped down ill have a look at that. My best bet i think would be to send it to guessworks.