[rkcarguy]

Christ, where did you get your information?
First, the 3 stage does have it's own unique double vtec solenoids.
2nd, it is a lean burn engine, but is uses it's knock sensor to sneak up on the lean burn "edge" instead of a wideband O2, which is actually better because it's much easier to tune if your running a chipped OBD-1 ecu like I plan on because the OBD-2 version is non-chipable and near impossible to find.
The rest of the parts cross over to USDM D16Y8 parts except the cams and rockers. Unless you are one of those idiots that never changes your oil, you should NEVER need to replace any of these parts before the life of the engine has passed. The head gasket timing belt water pump belts hoses valve cover gaskets are all avail at the honda dealer.
Lastly all of the externals-intake, exhaust mani, distributor, wiring harness, from the D15B/Z will bolt onto this engine and drop right in.
The Apex-i VAFC has the option of modifying/controlling VTEC ran piggyback with the stock ecu. There is an imput wire and output wire for VTEC. In conditions where the ecu has no vtec and you have a VTEC motor, you can tune the VAFC to activate it and richen the mixture as needed. To run the 2nd stage of VTEC you simply run the 1st stage from the stock Z1 ECU and the 2nd stage via the VAFC. The solenoids are only one wire each and very simple.
The only thing this engine lacks is roller rockers, as there wasn't room with all the lobes and cams under that valve cover.

Basjoos, by no means am I pushing you to replace your engine, it's just exciting to know that you are getting that kind of MPG and are not maxed out...there is more that can be done and better numbers can be had. I think this setup can obtain tripple digit mpg figures and invite you to check out my post "VTEC-E in custom built car".