Ive been doing some re-search and ive gone thru some trial and error with parts for my car which ive learned alot from. But ive found very few stock K20A3 pushing above 400HP and by the looks of it the 2 that ive found had modified the head such as homeboii slowrsx with the built head with supertech everything lol. Also there was a video on youtube that is couple years old that had a k20a3 stock bottom end with a vtec killer set up valvetrain of a k20a2, turbo making about 416hp. Now with my set up i dont think i will push the engine beyond 400 just because there is not alot of evidence that it can hold that power for too long, but it is possible to make that type of powerband. So this is my set-up right now on stock internals K20A3:
Turbonetics 60 Trim Turbocharger w/ Intercooler
T3/T4 Cast Manifold
Turbosmart Wastegate
FIC 1000cc Injectors
AEM 340cc Fuel Pump
Stock Clutch
Premium 93 Octain
PRB Intake Manifold
REV HARD Blow Off Valve
Thermal R&D 3in Exhaust
Made 275HP at 15PSI of Boost
The only downfall of this was the clutch, it was giving out and slipping. Also the fuel duty cycle was getting too high and the reason behind this was i wasnt running a fuel return setup.The oem fuel pump assembly has a built in restrictor that needs to be bypassed and the car needs to run a external fuel pressure regulator to increase fuel pressure without maxing out the injectors. The new setup will be:
Competition Clutch Stage 4
Exedy Light Weight Flywheel
RBC Intake Manifold w/ Blox 70mm Throttle Body
Deatschworks Fuel Return Kit
E85
So with this we should be making about 350hp without raising the boost pressure, just running E85. But we shall see once i finish it up
Forgot to mention my Engine Management, im using Hondata K-pro V4. Im also aware since 2 years ago they actually made a standalone made by Haltec. Which for the price similar to kpro, i would run haltec because its software would be more up to date. Not only that but theres versions of that standalone that gives you more programs to be able to do more. And with the kpro most likely becoming outdated soon, plus the ECM becoming harder to find due to the vehicle becoming older, plus they make a wiring harness for that standalone to be plug n play, you can run Haltec and be good to go.