Differences in 2.7T engines

[vtraudt]

I want to buy a spare motor. I have "APB" in my 2002 Allroad 6 spd.
Before biting on one of the offers out there. What are the differences between the various 2.7T engine versions out there? Currently stage 2 on the way to stage 3, future RS6:

- Bottom end (how strong)
- Flow (heads, valves, etc.)

The versions


S4
1997*-*2003 2.7 Turbo AGB
A4
1999*-*2001 2.7 Turbo AJK
A6
1999*-*2003 2.7 Turbo AJK
A6
1999*-*2003 2.7 Turbo APB
Allroad Quattro 2001*-*2003 2.7 Turbo APB
S4
1998*-*2001 2.7 Turbo APB
A6
2000*-*2003 2.7 Turbo ARE
Allroad Quattro 2000*-*2003 2.7 Turbo ARE
A4
2000*-*2003 2.7 Turbo ASJ
S4
2000*-*2003 2.7 Turbo ASJ
A6
2000*-*2003 2.7 Turbo AZA
A4
2001*-*2001 2.7 Turbo AZB
S4
2000*-*2001 2.7 Turbo AZB
A4
2002*-*2003 2.7 Turbo AZR
S4
2000*-*2003 2.7 Turbo AZR