Si to VTEC Engine Conversion (Various Electronics)

[Digital Overdrive]

I have a few questions for anyone, (preferably themselves) swapped a 97 Prelude non-SH motor into a 93 Prelude 4WS Si. From what I have gathered, the intake manifold and exhaust manifold from H23A1 and H22A1 are identical, so that shouldn't be a problem. I will also have the H23A1 distributor and coil instead of H22A4. The tranny is a 95 MT VTEC tranny with LSD installed. Now here is the question...

I am planning on using the stock ECU from my Si, I would like to keep the 4WS, set my rev limiter higher (stock H22A4 rev limit), and have the VTEC fuel and switchover programmed in. I have heard from an unrelaible source that the 93 Si could might possibly probably maybe have the same identical wiring harness as the VTEC, and that the ECU also has the pins for it but are non-funtioning.

Does anyone know whether or not this info is for sure, because in some ways it makes sense and some does not. And feel free to correct me if my information is WITHOUT A DOUBT correct in the top section, I just want to know what I need before the swap is underway. Thanx

[Digital Overdrive]

BTW, let me know as much about this motor as everyone can gather! I need to hear facts, opinions, and some BS. But please specify if the info is any of the above. Thanx

[AcesHigh]

Hey.

The h23a1 distributor and the external coil plugs right into h22a harness, so no pin changes are necessary.

However, I don't believe the p14 ecu has VTEC capabilities. Maybe you can chip it and alter the rev limiter; but I've never heard of anyone doing this. It would be nice to retain 4WS with the swap, but I'm doubtful. Going with the p13 seems easiest here.

Also, the h23a1 exhaust manifold DOES NOT work with the h22a. At least mine didn't, I ended up buying a performance header in place of the stock manifold.

[Digital Overdrive]

Thanks for the reply ace, but there's still a question left unanswered

VTEC solenoid, does my wiring harness have this plug?

Plus the P14 will be reprogrammed by Erick Aguilar, and claims he knows exactly what to do to it for the VTEC. I asked him about the 93 SI harness plugging into the VTEC solenoid and he wasn't sure of the 93 model. I was going to buy a DC Sports 4-2-1 2 piece header for it anyways, might as well go ahead and get it. By the way, much respect for you Ace, you seem to be educated in all the fields I am interested in knowing about. try to lend me a hand with my last questions ite? Thanx

[AcesHigh]

Nope, the p13 and the p14 are exactly the same, except the p14 is missing the VTEC related pins.

If it helps, here is a pinout of the p13 ecu:

A1 brn Injector #1
A2 yel Injector #4
A3 red1 Injector #2
A4 grn/yel VTEC Solenoid Valve
A5 blu Injector #3
A6 or/wht HO2S heater coil
A7 grn/blk1 PGM-FI Main Relay coil
A8 grn/blk2 Shorted to A7
A9 blk/blu IAC Valve
A10 - -
A11 red2 EGR Control Solenoid
A12 blu/red Condenser Fan Relay
A13 blu/wht MIL
A14 - -
A15 red/blu A/C Clutch Relay
A16 wht/grn Alternator
A17 pink IAB Solenoid Valve
A18 - -
A19 wht Intake Control Solenoid Valve
A20 red/grn EVAP Purge Control Solenoid
A21 yel/grn1 ICM
A22 yel/grn2 Shorted to A21
A23 blk1 GND
A24 blk2 GND
A25 yel/blk PGM-FI Main Relay (power)
A26 blk/red VTEC Pressure Switch (GND)
B1 yel/blk PGM-FI Main Relay (power)
B2 brn/blk GND
B3 - -
B4 - -
B5 blu/blk To A/C Switch
B6 - -
B7 - -
B8 red/grn PSP Switch
B9 blu/red Starter Cut Relay
B10 orn2 VSS
B11 orn3 CYP
B12 wht CYP
B13 orn/blu TDC
B14 wht/blu TDC
B15 blu/grn CKP
B16 blu/yel CKP

D1 wht/yel Battery
D2 grn/wht1 Brake Switch
D3 red/blu KS
D4 brn/wht SCS
D5 - -
D6 lt blu or lt grn VTEC Pressure Switch
D7 lt grn/red Data Link Connector
D8 - -
D9 wht/red ALT
D10 grn/blk ELD
D11 red/blk TP Sensor
D12 wht/blk EGR Valve Lift Sensor
D13 yel/blu ECT Sensor
D14 wht HO2S Sense
D15 red/yel IAT Sensor
D16 - -
D17 wht/blu MAP Sensor
D18 - -
D19 red/wht EGR Valve Lift Sensor
D20 yel/wht TP Sensor
D21 blu/wht MAP Sensor
D22 grn/wht2 TP Sensor

I don't think there is a way to activate VTEC using the p14. But good luck man.

[Digital Overdrive]

Hmmmmm..

I see ur point man. I guess I could get him to reprogram it to where I can bump up the fuel performance, and simply use an external VTEC switch like V-AFC. I can set it at the stock VTEC switchover point and maybe find some way to bump up the fuel a that RPM, I dunno. Thanx for helping me out bro.

[Digital Overdrive]

Another option...

Buy a friggin P13 ECU and wiring Harness and call it a day. :-D