Questions about 1275 motor swap
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- RyanWilson
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Questions about 1275 motor swap
Hello all!
I'm new here and to the world of Morris Minors. Two weeks ago I bought my first car, a 1960 Morris Minor 1000 Saloon! (Picking it up Saturday)
We have 2 1275 motors and ribbed case transmitions that were for my dads 58 A/H Sprites. One of the motors is in the sprite, and the other is sitting next to it.
What I was wondering is if a 1275 motor and ribbed case transmition out of a later sprite or midget will just bolt into my minor, or will some things have to be changed? Any and all information anyone can give will be extremely helpful! I know very little about them, and my dad is only familiar with sprites.
Thanks! Ryan Wilson
P.S. ~Are there any books out there that might be of help to me?
I'm new here and to the world of Morris Minors. Two weeks ago I bought my first car, a 1960 Morris Minor 1000 Saloon! (Picking it up Saturday)
We have 2 1275 motors and ribbed case transmitions that were for my dads 58 A/H Sprites. One of the motors is in the sprite, and the other is sitting next to it.
What I was wondering is if a 1275 motor and ribbed case transmition out of a later sprite or midget will just bolt into my minor, or will some things have to be changed? Any and all information anyone can give will be extremely helpful! I know very little about them, and my dad is only familiar with sprites.
Thanks! Ryan Wilson
P.S. ~Are there any books out there that might be of help to me?
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The basic ins and outs are discussed in Owen Burton's 'Morris Minor Modification Manual'. It has a lot of useful info about compatability between cars although there are a few untruths in there of which Cam could probably shed some light......
Older and more confused than I could ever imagine possible.
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Yes, have a bucket of common sense handy when reading THAT manual!! All the info is not bad and it does give some good overviews.
The 1275 Spridget engine should go in quite easily and mate to the ribcase transmission. Can't think of any specific problems to watch out for, but if you come accross any problems when doing the conversion, give us a shout and we'll advise!
I personally have done the Ital conversion with a 5-speed 'box but the 1275 Midget conversion is much easier. I think Kevin is doing (or starting to do) one, so he is probably more up on the details than I am.
The 1275 Spridget engine should go in quite easily and mate to the ribcase transmission. Can't think of any specific problems to watch out for, but if you come accross any problems when doing the conversion, give us a shout and we'll advise!
I personally have done the Ital conversion with a 5-speed 'box but the 1275 Midget conversion is much easier. I think Kevin is doing (or starting to do) one, so he is probably more up on the details than I am.
- RyanWilson
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Over your side of the pond a useful contact is Randolph Williams who should be able to let you know what is available over there to do the conversion http://members.aol.com/dolphnx/.
I will be soon starting to do a Midget engine conversion but to the 1098cc ribcase gearbox, the main things that will have to be done is the rear engine plate has to be machined or a new one made and also the timing cover breather has to be altered, and the thermostat housing from a Minor will have to be used to enable a reasonable top hose alighnment. Over here most people use a single carb rather than the twins the Midget uses as its simpler to look after, the other thing you may have to do if using the matching gearbox is to use a hydraulic clutch conversion kit as the midget one is stronger and can give a snatchy action when used in the Minor, the Owen Burton book which is mentioned is useful as a guide is available from http://www.morris-minor.co.uk.
You will also need to upgrade the brakes to discs to help stop the car with the increased power and also change the front bushes to poly bushes due to the increased stresses caused by the disc brakes.
I will be soon starting to do a Midget engine conversion but to the 1098cc ribcase gearbox, the main things that will have to be done is the rear engine plate has to be machined or a new one made and also the timing cover breather has to be altered, and the thermostat housing from a Minor will have to be used to enable a reasonable top hose alighnment. Over here most people use a single carb rather than the twins the Midget uses as its simpler to look after, the other thing you may have to do if using the matching gearbox is to use a hydraulic clutch conversion kit as the midget one is stronger and can give a snatchy action when used in the Minor, the Owen Burton book which is mentioned is useful as a guide is available from http://www.morris-minor.co.uk.
You will also need to upgrade the brakes to discs to help stop the car with the increased power and also change the front bushes to poly bushes due to the increased stresses caused by the disc brakes.
Cheers
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
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- RyanWilson
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You need to fit the Minor front engineplate to the Midget engine but the standard back one has the hole for the oil pump in a different location so either needs a new one or the existing one modified, as I have not got this far yet I cannot say exactly what the differences are.
Cheers
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
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- RyanWilson
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Ryan if you email me direct I will scan the section from the Owen Burton book this will explain it in more detail, kevin.daly1@btinternet.com
Cheers
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
Kevin
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- d_harris
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On top of OPO my mums 'originally named' traveller (OPO are the letters on the plate) we have a resto project going on with a (64?) Sprite, which we got with a 1275 goldseal engine, lining it and the sprite box up next to a minor engine and box they appear to be of the same dimensions, (I guess the engine would be anyway still being A series) so surely with a sprite box it should drop straight in?
or am i being thick?
or am i being thick?
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Sorry to dissapoint you Dan but the front & rear engine plates are not the same, the timing chest breather has to be altered and if you have a 1098cc the water valve for the heater needs to be changed/altered, there are clutch differences and the carb/manifold/exhaust also needs sorting out and if retaining the original box the flywheel needs to be altered as well and to get better alignment a different thermostat housing is required.
Then you need to upgrade the brakes etc to cope with the increased power, so there are a few bits and pieces to be sorted out.
Then you need to upgrade the brakes etc to cope with the increased power, so there are a few bits and pieces to be sorted out.
Cheers
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
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Hi Dan,
If you use the box that came with the engine you can avoid changing the engine backplate.
The rest of the work is covered in Kevin's list. If you want to shortcut some of it you can run the 1275 using the minor carb, manifold and exhaust. You'll loose a some of the power advantage this way, but it is still a significant improvement.
It the clutch lever is similar enough you can also keep the same clutch etc.. though the MG version has a reputation for low comfort.
If you use the box that came with the engine you can avoid changing the engine backplate.
The rest of the work is covered in Kevin's list. If you want to shortcut some of it you can run the 1275 using the minor carb, manifold and exhaust. You'll loose a some of the power advantage this way, but it is still a significant improvement.
It the clutch lever is similar enough you can also keep the same clutch etc.. though the MG version has a reputation for low comfort.
Ray. MMOC#47368. Forum moderator.
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block

- RyanWilson
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Kevin, you have mail!
If that's the truth, then Kevin must have miss understood me. I plan on using the motor AND transmition (already together) out of a later sprite or midget. That being the case, what do I need to change beside the brakes? I shouldn't need to upgrade the clutch then, do I?
Thanks, Ryan
If that's the truth, then Kevin must have miss understood me. I plan on using the motor AND transmition (already together) out of a later sprite or midget. That being the case, what do I need to change beside the brakes? I shouldn't need to upgrade the clutch then, do I?
Thanks, Ryan
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Have never used the 1275 clutch but it is often complained about.I shouldn't need to upgrade the clutch then, do I?
Ray. MMOC#47368. Forum moderator.
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block
Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
Oct 06: back from Dresden with my Trabant 601 Kombi
Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
June 07 - back from Zwickau Trabi Treffen
Aug 07 & Aug 08 - back from the Lands End to Orkney in 71 pickup
Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block

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Ryan I have sent you the scanned pages from Owen Burtons book however most of relater to our Marina / Ital cars and not the Midget.
I though the engine plates had to be changed so that the engine moutings stayed the same but as I have not done it yet I may be wrong.
If the complete running gear from the Midget is used it gives a very heavy clutch action which is why over here a hydraulic lift kit is recommended, its because the flywheel & clutch are smaller than the minor ones which is why I am sticking with the Minor ones.
As for the brakes the earlier cars like yours only have 7" drums and the later cars have 8" drums and neither are really suitable for stopping the car with the increased performance although there I am led to believe quite a few 1275cc conversions over here using the 8" drums, however most insurance companies wont insure you unless a disc brake conversion has been carried out.
I though the engine plates had to be changed so that the engine moutings stayed the same but as I have not done it yet I may be wrong.
If the complete running gear from the Midget is used it gives a very heavy clutch action which is why over here a hydraulic lift kit is recommended, its because the flywheel & clutch are smaller than the minor ones which is why I am sticking with the Minor ones.
As for the brakes the earlier cars like yours only have 7" drums and the later cars have 8" drums and neither are really suitable for stopping the car with the increased performance although there I am led to believe quite a few 1275cc conversions over here using the 8" drums, however most insurance companies wont insure you unless a disc brake conversion has been carried out.
Cheers
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
Kevin
Lovejoy 1968 Smoke Grey Traveller (gone to a new home after13 years)
Herts Branch Member
Moderator MMOC 44706
- RyanWilson
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Thanks Kevin!
Over time I will figure everything out. (I hope)
I just got back from picking it up! WOW!!! That is a FUN car to drive!!!! The best part of the ride home was watching all the people pass our truck (we brought if home on a trailer) and see the HUGE grins on their faces! Needless to say, mine was bigger thought! I can't weight till morning so I can drive it! Thanks for everyone’s help, especially Kevin! Later, Ryan
Over time I will figure everything out. (I hope)
I just got back from picking it up! WOW!!! That is a FUN car to drive!!!! The best part of the ride home was watching all the people pass our truck (we brought if home on a trailer) and see the HUGE grins on their faces! Needless to say, mine was bigger thought! I can't weight till morning so I can drive it! Thanks for everyone’s help, especially Kevin! Later, Ryan