A Series Capacity
Discussion
Hello there! Im after some real technical advice so i thought that i'd try a proper forum first!
Assuming that the crank stroke is standard and that the cylinder head is removed..
How can i measure what capacity the engine is without removing pistons etc?
What gear would i need and how accurage would it be? The previous owner reckons that the car was a 1380 so what size pistons should i expect?
Mike
Assuming that the crank stroke is standard and that the cylinder head is removed..
How can i measure what capacity the engine is without removing pistons etc?
What gear would i need and how accurage would it be? The previous owner reckons that the car was a 1380 so what size pistons should i expect?
Mike
You need to measure stroke and bore, which you could do with the head off without removing pistons. If you're only using it to confirm the approximate capacity a simple ruler would probably be accurate enough. Alternatively, get the power output measured and see whether that feels about right for the claimed capacity and state of tune.
Happy days, thanks for all the help guys. Theres certainly some very knowledgable people around these parts..
While im here, does anyone know the following:-
What are the stock valve sizes for the 12g940 head?
Also, can you anyone tell me how you ID a 1275 cooper S block from a stock 1275 one?
Thanks again,
Mike
While im here, does anyone know the following:-
What are the stock valve sizes for the 12g940 head?
Also, can you anyone tell me how you ID a 1275 cooper S block from a stock 1275 one?
Thanks again,
Mike
Stock Valves are 33mm Inlet - 29mm Exhaust. If the Valves are 35mm on Inlet they are MG Metro (12G940 Casting)/Cooper S (AEG Prefix Casting) and are classified as such as Big valve heads. They maintain production valves centres.
Cooper 'S' Block has Solid tappet Chest / As do standard A-series. There are identifying features that distinguish the 'S' Block but they escape me at the minute. Cooperman and/or Guru1071 will be along in a minute... Take care - commonest trick in the book is to try and pass off Non 'S' stuff as the genuine article.
A+ Blocks all have pressed steel tappet chest covers.
Hope that helps.
Cooper 'S' Block has Solid tappet Chest / As do standard A-series. There are identifying features that distinguish the 'S' Block but they escape me at the minute. Cooperman and/or Guru1071 will be along in a minute... Take care - commonest trick in the book is to try and pass off Non 'S' stuff as the genuine article.
A+ Blocks all have pressed steel tappet chest covers.
Hope that helps.
Edited by FWDRacer on Thursday 27th November 10:52
FWDRacer said:
Hope that helps.
not really, your the wrong way round........ Edited by FWDRacer on Thursday 27th November 10:52
all small bore blocks have the removable doors on the rear.
as do all cooper s blocks (which are classed as large bore no matter the size)
non cooper s 1275 blocks (again, large bore) dont have the doors (in either a or a plus type)
its a common trick to claim that mk3 cooper s's didnt have the doors as it makes a 1275 a series block more valuable.
to be able to tell a bare cooper s block from a bare small block is just a case of looking at details (like core plug size), it can be difficult 'at a glance' if the engine is built up or in a car and in the cornor of a dark garage
there is nothing special about an s block, its actually far weaker than the normal large bore block, id never use one in an engine (ive got a few chucked under the bench....). the only use they are is to go in a concours high value s. for performance or motorsport use they are a liability.
You've got that the wrong way round!
Cooper S blocks are the only 'big bore' blocks to have tappet chest covers, all other A series 1300 (and A+ for that matter) have solid blocks.
All Big Bore blocks (that is 1275, 1071, 970, A and A+) have 2 pressed core plugs at the end of the block - just above the steady bar, small bore blocks only have one.
So basically, if you've got: Tappet chest covers and two core plugs at the end, you've got an S block
Cooper S blocks are the only 'big bore' blocks to have tappet chest covers, all other A series 1300 (and A+ for that matter) have solid blocks.
All Big Bore blocks (that is 1275, 1071, 970, A and A+) have 2 pressed core plugs at the end of the block - just above the steady bar, small bore blocks only have one.
So basically, if you've got: Tappet chest covers and two core plugs at the end, you've got an S block
Dino42 said:
You've got that the wrong way round!
Cooper S blocks are the only 'big bore' blocks to have tappet chest covers, all other A series 1300 (and A+ for that matter) have solid blocks.
All Big Bore blocks (that is 1275, 1071, 970, A and A+) have 2 pressed core plugs at the end of the block - just above the steady bar, small bore blocks only have one.
So basically, if you've got: Tappet chest covers and two core plugs at the end, you've got an S block
s blocks only have ONE core plug at the end, four total.....Cooper S blocks are the only 'big bore' blocks to have tappet chest covers, all other A series 1300 (and A+ for that matter) have solid blocks.
All Big Bore blocks (that is 1275, 1071, 970, A and A+) have 2 pressed core plugs at the end of the block - just above the steady bar, small bore blocks only have one.
So basically, if you've got: Tappet chest covers and two core plugs at the end, you've got an S block
So who is confused now (lol)?
Let's summarise this then:
The genuine Cooper 'S' block will have:
Removeable cam chest covers, a single water-jacket core plug at the end of the block, drilling for 10 head studs and one head bolt, a stroke of over 3" if a 1275, less if a 1071 or a 970, studs for the main bearing caps, con-rods with a horizontal split line for big-end caps, (as do all 'big-bore' engines whereas the 998 has a sloping split line). There is only one oil-gallery core plug at each end.
The 1275 non-'S' block, pre A-plus will not have the 11 head stud/bolt holes unless modified, will not have removable cam chest covers, will have 2 oil-gallery core plugs at each end and will have bolts for the main bearing caps, otherwise as the 'S' blocks.
The A-Plus blocks have external ribbing on the front of the block, a smaller distributor drive hole with one 3/8" unf fixing bolt hole on the forward side of the hole. The alternator bracket holes are also nearer the front and a shorter bracket is fitted.
I think that is all correct.
Peter
Let's summarise this then:
The genuine Cooper 'S' block will have:
Removeable cam chest covers, a single water-jacket core plug at the end of the block, drilling for 10 head studs and one head bolt, a stroke of over 3" if a 1275, less if a 1071 or a 970, studs for the main bearing caps, con-rods with a horizontal split line for big-end caps, (as do all 'big-bore' engines whereas the 998 has a sloping split line). There is only one oil-gallery core plug at each end.
The 1275 non-'S' block, pre A-plus will not have the 11 head stud/bolt holes unless modified, will not have removable cam chest covers, will have 2 oil-gallery core plugs at each end and will have bolts for the main bearing caps, otherwise as the 'S' blocks.
The A-Plus blocks have external ribbing on the front of the block, a smaller distributor drive hole with one 3/8" unf fixing bolt hole on the forward side of the hole. The alternator bracket holes are also nearer the front and a shorter bracket is fitted.
I think that is all correct.
Peter
Cooperman said:
So who is confused now (lol)?
Let's summarise this then:
The genuine Cooper 'S' block will have:
Removeable cam chest covers, a single water-jacket core plug at the end of the block, drilling for 10 head studs and one head bolt, a stroke of over 3" if a 1275, less if a 1071 or a 970, studs for the main bearing caps, con-rods with a horizontal split line for big-end caps, (as do all 'big-bore' engines whereas the 998 has a sloping split line). There is only one oil-gallery core plug at each end.
The 1275 non-'S' block, pre A-plus will not have the 11 head stud/bolt holes unless modified, will not have removable cam chest covers, will have 2 oil-gallery core plugs at each end and will have bolts for the main bearing caps, otherwise as the 'S' blocks.
The A-Plus blocks have external ribbing on the front of the block, a smaller distributor drive hole with one 3/8" unf fixing bolt hole on the forward side of the hole. The alternator bracket holes are also nearer the front and a shorter bracket is fitted.
I think that is all correct.
Peter
ahhh...Let's summarise this then:
The genuine Cooper 'S' block will have:
Removeable cam chest covers, a single water-jacket core plug at the end of the block, drilling for 10 head studs and one head bolt, a stroke of over 3" if a 1275, less if a 1071 or a 970, studs for the main bearing caps, con-rods with a horizontal split line for big-end caps, (as do all 'big-bore' engines whereas the 998 has a sloping split line). There is only one oil-gallery core plug at each end.
The 1275 non-'S' block, pre A-plus will not have the 11 head stud/bolt holes unless modified, will not have removable cam chest covers, will have 2 oil-gallery core plugs at each end and will have bolts for the main bearing caps, otherwise as the 'S' blocks.
The A-Plus blocks have external ribbing on the front of the block, a smaller distributor drive hole with one 3/8" unf fixing bolt hole on the forward side of the hole. The alternator bracket holes are also nearer the front and a shorter bracket is fitted.
I think that is all correct.
Peter
but 1300gt blocks are non s, but are drilled for the 10 studs, one bolt.......
http://uk.youtube.com/watch?v=SelN1bWm3V8&feat...
Even got a decent amount of camber to get round corners
Even got a decent amount of camber to get round corners
Edited by cone on Friday 28th November 16:45
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