Engine block ID, M28.11 or M28.12
05-07-2023, 09:52 AM
#1
Rennlist Member
Thread Starter
Engine block ID, M28.11 or M28.12
Hello everybody. So, my car is a euro 1983 928s with a M28.11 engine. I have also a spare complete engine. According to previous owner this engine was taken from an euro 1982 928s, possibly an auto car. I haven't checked the engine stamp on this spare engine and I don't have this engine at home. As I understand it, if the block has been changed, the engine may not have any or the correct stamps. If this spare engine really IS taken from a car with an automatic transmission, what should I look for in terms of mounts, brackets, bolt-holes etc.?
Or to to put it simply: If I wanted to swap my M28/11 for this one and it is a M28/12 engine, what are the real differences and could it even be done?
The reason for asking this is ofcourse to determine what to do with my spare engine. I'm going to go thru it during this summer and see what I really got...
Thankful in advance for all info you can give in the matter..!
Or to to put it simply: If I wanted to swap my M28/11 for this one and it is a M28/12 engine, what are the real differences and could it even be done?
The reason for asking this is ofcourse to determine what to do with my spare engine. I'm going to go thru it during this summer and see what I really got...
Thankful in advance for all info you can give in the matter..!
05-07-2023, 12:11 PM
#2
Rennlist Member
The only difference is the flexplate or the pressure plate and the spider has a different vacuum port for the automatic shifting modulation.
Last edited by Darklands; 05-07-2023 at 12:15 PM.
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WestInc (05-07-2023)
05-07-2023, 12:14 PM
#3
Archive Gatekeeper
Rennlist Member
Rennlist Member
The part number for replacement short block from Porsche (when they were available) is identical between the two.
Other than the obvious flywheel and flexplate difference, the only difference between an M28.11 and an M28.12 that I can think of is the vacuum hardline that comes off the intake plenum and goes to the (automatic) transmission. There may be other trivial differences but there's no issue swapping an .11 with a .12.
Other than the obvious flywheel and flexplate difference, the only difference between an M28.11 and an M28.12 that I can think of is the vacuum hardline that comes off the intake plenum and goes to the (automatic) transmission. There may be other trivial differences but there's no issue swapping an .11 with a .12.
05-07-2023, 01:11 PM
#4
Rennlist Member
Thread Starter
The part number for replacement short block from Porsche (when they were available) is identical between the two.
Other than the obvious flywheel and flexplate difference, the only difference between an M28.11 and an M28.12 that I can think of is the vacuum hardline that comes off the intake plenum and goes to the (automatic) transmission. There may be other trivial differences but there's no issue swapping an .11 with a .12.
Other than the obvious flywheel and flexplate difference, the only difference between an M28.11 and an M28.12 that I can think of is the vacuum hardline that comes off the intake plenum and goes to the (automatic) transmission. There may be other trivial differences but there's no issue swapping an .11 with a .12.
