ECU/ECM Question
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ECU/ECM Question
I have a ‘90 Civic ED6. I believe yit has the PM5 ECU. Was wondering if a Hondata S300 v3 would just plug right on up to it. I’m doing an LSVTEC with a B18b1 block and GSR Head. So I need to know if I have to get a P72 and an S300, or if I could use the PM5 (stock ECU) and a Hondata S300, or if I could just use the Hondata as a stand-alone ECU. Keep in mind my strong suit is mechanical, not in Computers, wiring, and all this. I know my swap intio my ED6 is gonna require some modifications of the harness, but I’m just trying to make sure I’m getting all of my stuff correct. And learn monst importantly! 
thanks!
thanks!
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From: Flyover Country West Annex
Re: ECU/ECM Question
Might be unwise to pursue a full swap until you have some research down. Direct from the specs for the S300 V3 on Hondata's own website...
Model ListCivic 1992-2001
Integra 1992-2000
Prelude 1992-2000
Your ECU is not from one of those vehicles, so it would not be compatible.
Model ListCivic 1992-2001
Integra 1992-2000
Prelude 1992-2000
Your ECU is not from one of those vehicles, so it would not be compatible.
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Re: ECU/ECM Question
Okay, so I did some looking around online. Pretty sure this will allow me to keep my stock wiring harness and use an OBD1 ECU, or Hondata S300v3, please correct if I’m wrong.
Re: ECU/ECM Question
I've been out of the game since the S300 came out, but my understanding is that it should work on any OBD1 Civic ECU - so it doesn't necessarily have to be a P72....a P28 could also work, as could others.
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Re: ECU/ECM Question
Yep. It’s an OBD0 -to- OBD1 conversion harness. I just wanna run my stock wiring harness and not fiddle with much except the distributor wiring, and injector pigtails. And this will allow me to keep the ED6 wiring harness correct?
Re: ECU/ECM Question
S300 is not a standalone, it is a piggyback, basically a board that works with the main board.
Nonetheless, if you're going ls/vtec, you'll need a vtec dizzy meaning at least a rewire of the distributor plugs to match your dizzy and run the vtec wire. Also depends on if you'll be running a separate o2 sensor or tee'ing off the wideband because you'll also need to wire the 4 wire o2 sensor, rig something for your cel jumper, possibly butterflies, etc.
Nonetheless, if you're going ls/vtec, you'll need a vtec dizzy meaning at least a rewire of the distributor plugs to match your dizzy and run the vtec wire. Also depends on if you'll be running a separate o2 sensor or tee'ing off the wideband because you'll also need to wire the 4 wire o2 sensor, rig something for your cel jumper, possibly butterflies, etc.
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Re: ECU/ECM Question
S300 is not a standalone, it is a piggyback, basically a board that works with the main board.
Nonetheless, if you're going ls/vtec, you'll need a vtec dizzy meaning at least a rewire of the distributor plugs to match your dizzy and run the vtec wire. Also depends on if you'll be running a separate o2 sensor or tee'ing off the wideband because you'll also need to wire the 4 wire o2 sensor, rig something for your cel jumper, possibly butterflies, etc.
Nonetheless, if you're going ls/vtec, you'll need a vtec dizzy meaning at least a rewire of the distributor plugs to match your dizzy and run the vtec wire. Also depends on if you'll be running a separate o2 sensor or tee'ing off the wideband because you'll also need to wire the 4 wire o2 sensor, rig something for your cel jumper, possibly butterflies, etc.
Re: ECU/ECM Question
p72/p06/p28. You'll need the ecu to be chipped, might as well get it set up for datalogging and if its a p06 converted to vtec. Its an extra 5 bucks for the parts.
Pick up neptune rtp or hondata your choice.
Conversion harness, get the addon harness unless you want to wire in your own vtec wires/butterflies/4 wire o2/code jumper
Depinn and repinn your dizzy or get a harness
If you have a resistor box still you'll have to convert to obd1, you can find the conversion process by searching. You can reuse the obd0 plugs by trimming some of the plastic either off the injector or the harness.
Pick up neptune rtp or hondata your choice.
Conversion harness, get the addon harness unless you want to wire in your own vtec wires/butterflies/4 wire o2/code jumper
Depinn and repinn your dizzy or get a harness
If you have a resistor box still you'll have to convert to obd1, you can find the conversion process by searching. You can reuse the obd0 plugs by trimming some of the plastic either off the injector or the harness.
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Re: ECU/ECM Question
p72/p06/p28. You'll need the ecu to be chipped, might as well get it set up for datalogging and if its a p06 converted to vtec. Its an extra 5 bucks for the parts.
Pick up neptune rtp or hondata your choice.
Conversion harness, get the addon harness unless you want to wire in your own vtec wires/butterflies/4 wire o2/code jumper
Depinn and repinn your dizzy or get a harness
If you have a resistor box still you'll have to convert to obd1, you can find the conversion process by searching. You can reuse the obd0 plugs by trimming some of the plastic either off the injector or the harness.
Pick up neptune rtp or hondata your choice.
Conversion harness, get the addon harness unless you want to wire in your own vtec wires/butterflies/4 wire o2/code jumper
Depinn and repinn your dizzy or get a harness
If you have a resistor box still you'll have to convert to obd1, you can find the conversion process by searching. You can reuse the obd0 plugs by trimming some of the plastic either off the injector or the harness.
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Re: ECU/ECM Question
basically a b20 is CRX powerplant.. more than 65% on the road run non-vtec. USually a solinieid or VTEC head will enguage VTEC. Just keep in mid the TAC will not read when vtec -- VTECS.
Most conversions today use kits. RYwire.. offers complete obd to obd jumpers.. including vehicles which have complete changeovers ie: piggy back..
I suggest tucking. replace battery. few wires needed incase codes or errors are thrown. Keep in mind that rywire only does complete changeovers.
There are many manuals and things online to day which referene codes.. mainly 3 or 4 codes today between people who are converting to JDM.
Usualy.. knock, o2.. rich/lean.
Up to u..
usually ECU swaps will fix it.. EBAY.. hondata..
(hasport)
Most conversions today use kits. RYwire.. offers complete obd to obd jumpers.. including vehicles which have complete changeovers ie: piggy back..
I suggest tucking. replace battery. few wires needed incase codes or errors are thrown. Keep in mind that rywire only does complete changeovers.
There are many manuals and things online to day which referene codes.. mainly 3 or 4 codes today between people who are converting to JDM.
Usualy.. knock, o2.. rich/lean.
Up to u..
usually ECU swaps will fix it.. EBAY.. hondata..
(hasport)
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