Sorry v. newbie Q: difference between TD engines

[blinkyeatu]

i know this is probably pretty basic but im starting to get pretty confused with the different engine codes anyone able to explain the differences;
Xud9te
xud9ai
dhy
d8a
is there anymore, which is the best 
buying a bosch pump with free d8a engine attached was told it was stronger.

[Mattcheese31]

Never heard of ai before, they're all basically the same mate, d8a is the older block which some think is stronger, no one has proof though

[cully]

think the D8a pump maybe ECU controlled so may not be suitable to retrofit onto an older xud9 engine

i may be wrong though

ignor me i ment DW8 pump

[blinkyeatu]

cheers guys
i found this for anyone else that might be wondering http://homepage.ntlworld.com/agmpcrepair...ngines.htm

[Dturbobooost]

D8A is the one you want , mainly for bosch pump and bigger turbo either T2 or K14 . DHY's supposively are prown more to rod failures ( myth i think ) as mine is still boosting strong after 30 ,000 odd miles at 30psi .