300whp on a JRSC? You're better off with a turbo, but here are some threads that may help:
https://www.honda-acura.net/forums/s...highlight=JRSC
https://www.honda-acura.net/forums/s...threadid=10810
Oh, and what could be better than information from a long-time JRSC owner himself?
Originally posted by newgsrdriver
Im selling my 95 JRSC'd GSR if you want to skip a step 
Heres your method for mayhem:
OBD1 GSR
JRSC
Hondata 2B Boost
Hondata intake manifold gasket
Kamikaze 2.5" header
Carsound 2.5" Cat
2.5" Exhaust
JR Boost upgrade pulley, CRV pulley, whetever floats your boat to get you to 8-9PSI.
3" Short Ram Intake
With the proper tuning, you shouldnt have a problem hitting 250whp with that setup.
In terms of getting that power to the ground....
Definitely a nice clutch (ACT HDSS)
Nice tires (whatever you can afford, Kumho 712's to Falken Azenis' to Toyo T1-S to Bridgestone S-03's etc etc)
Good suspension (again, this is all preference)
Just in terms of making power...the above equation can net you 250whp without nitrous...add a small 25 shot and you're definitely in business...
Since you seem to be well off, replace the Kamikaze/Carsound/Exhaust combo above with a full Hytech custom system (header/Renault Cat/Catback).
-Shingo
ps. Attempting 300whp on 12psi with a JRSC will net you some real heat issues...