Another nice feature of the later A+ 998 blocks is the press fit rods. While I have pressed many bushing in and sized over the years, you only need one piston pin snap ring to come adrift. I did look at having an 998 crank cut down to fit a 850 block. I think I was quoted $250/ $300 and decided to do something else. Steve (CTR)

I just think that a later thick flange block is a more worthy starting point for what you want to do, and since 998 and 1098 blocks are dimensionally identical, your ancient blocks can head off to recycling and the Y drilled 1098 crank can go into a superior block. You can line bore the mains of the 998 block and put a strap on the center cap and despite the longer stroke end up with a fairly reliable bottom end.

I would think that there is a 998 from the seventies somewhere near you that would be ideal. Maybe even a very late block from just before the A+ blocks, and those use the later front plate with the tensioner on the timing chain. All of a sudden you get some awesome sophistication. Of course, one can argue both for and against A+ blocks as they always have the tensioner, have stiffening ribs and thick flanges but use an allegedly lesser spec cast iron. I have no experience building performance engines with them so only offer the arguements I have heard. I have certainly seen thin flange small bore blocks that suffered catastrophic failures. 

Mur,

I've got two nearly complete 1100s. (blocks, rods and cranks)

I'm trying to build to Graham Russell specs.

Can you not find a thick flange 998 block to do this with? That would be my choice.

Thanks Spitz.

It is one of two 1100 blocks I have.

PVC engine is unknown.

I had read where the early 1100's were bored out 850's.

The numbers show post 1964 which should be good for a 68mm/1100 I am slowly building.

Does it have a PCV system.....?
Later than 64 anyway....not much I know

from a colleague....: "This engine number format was used by BL up to and including the 1971 model year.

The initial MG 1100 engines had 10GR-Ta-Hxxxxx, with later engines (mid-1964 on) having 10GRB-Ta-Hxxxxx with a PCV system."

Can anyone tell me when this 1100 block was manufactured.....10GBR-TA-H56832...?

Thanks in advance