Is it possible to use a vacum meter tool to slightly tune the d16 motor? These tools I know are used on carburated engines to tune for best air fuel mixture and so on. Basically you want to be as close to 20 as possible on the meter. If possible, where do you stick the tool's vacum line on? Do you stick it on any vacum connection on the throttle body or the manifold? For the tuning part, this is similar to the carburator, just enrich or lean out the mixture by adjusting the fuel pressure regulator. If this tuning is possible can some one let me know.
Thanks in advance!

 

To the best of my knowledge the fuel pressure regulator only "regulates" the fuel pressure pre injectors. What what makes the engine run richer or leaner is the duration of the injectors on position. If you want to tune an EFI engine the best way is with a wide band O2 sensor and a piggy back computer or programable ECU. Check out this site for great information and products. They have good how to tune videos:

http://www.innovatemotorsports.com/index.html

 

thanks!