I say treat it like a Honda B16 or H22 except it'll be RWD. Seriously going to be expensive to get anything out of it.
1) Use best fuel...our crappy Premium will have to do unless you start to order barrels.
2) I've heard the metal mesh "filter" by the MAF is a restriction so try removing it without digging into the maf sensor itself.
3) Clean MAF sensor properly and install a proper CAI.
4) Increase the exhaust diameter to approx 2 1/2".
5) I'm not quite sure of the availability of headers and cams farless for the expense.
6) Install in a relatively light chassis. 120Y anyone
In all relatively responsive engines (I believe the DE has a compression ratio over 10:1 stock), easily available (knowledge of the history might be a problem though as they can be over 20 years old) and they're easy to maintain.
The best thing I've been told is to simply convert it into a RB20DE+t just user a proper gasket and internals when you're ready to cross 7 psi
