[Vwdiesel] Still chasing an air leak, only there now when engine is hot

[James Hansen]

but the upper limits of performance are much lower in a mechanical 
engine... and increased performance equates to better mileage in a 
diesel.  To get cars that have 90mpg, you need to go with ECu controlled 
stuff.
To swap pumps, you also need to consider injected volume and max speed.
-james

Stephen Kraus wrote:
> This is why I like mechanical diesel better than ECU controlled injectors.
> Its all about timing, you can use most pumps with most engines, just
> adjusting timing is all you need.
>