Going the route of electronics with FastForwards setup makes it look really easy and fly. The homework looks as if it has been done there. To keep it simple. Its almost a "plug and play" harness to adapt the TDI electronics wiring/loom directly into the vanagon setup without all the hours of reading Bentley diagrams, cutting, splicing, heat shrinking, etc. it takes to wire in full electronics for other conversions otherwise.
I chose the route of mechanical on the TDI just from the standpoint that it kept an OldSchool feel to the conversion but also doesn't limit me in tunability when it comes down to maximum power. Not saying though that chipping does. I just believe personally when you weigh cost of electronics, chipping, custom mapping , turbo choices, etc. the mechanical route has alot higher ceiling for tunability and choices when it comes down to it. Custom mapping gets expensive unless you have the ability to do it on your own, and if you want to change, at the most you have two program choices at any given time.
For best fuel mileage, etc...its possible that electronics is the best way to go expecially since the electronic pump is so attuned to fine metering of fuel from the programming. I don't think mileage would be all that much greater...maybe 2 mpg or 3 depending on how you had them comparably setup.
The way I have the mTDI setup now I could adjust my pump timing in about 5 minutes from start to finish using the machined MKIV style pulley on the 4bt 12mm pump. That easy... nice crusing setup...then if I wanted to play for a little while it could easily be adjusted on the fly for a bit more fun. Same goes for the pump as well, full power adjust, star wheel adjust, etc. are all things easily learned and make things very tunable on these pumps.
Cost wise...depends on what you already have, etc. but I think it'd be comprable in the setup. AAZ engines are getting harder to find I've heard, going for 2.5k in CA salvage...
Anyways...my AM blurb...
Good luck in choosing your route!
