The older J series engines were derived from the engine used in the Austin A40 from the early 50's
In fact it's all but an exact copy, but with the relibility & oil leak problems engineered out & some improved performance engineered in.
None the less, it's a 1940's design & the A series engine is a quantum step forward in compactness, weight reduction, efficiency & performance.

There is not one single part that I know of that is interchangeable between the older J series engines & the A series engines. Nothing, ... & fitting a J series to a 1200 would be a retrograde step.

Thanks you for all of this.

I think I will asking for my money back quick smart....

Mind you it might be a very novel paperweight.

cheers

Don't knock the old J series, they still move the cars around fairly well, If you dont want to mod any of the old 60's model bluebird 1200's, and keep them granny spec, they're the way to go. Still cant beat the reliability of an A series though

Correct, but in a 1200, there are better choices that are readily available at affordable pricing.