420waipio

I need help on some parts for my swap and make sure that i got everything right!
*What i got with the swap - complete obd2 b18c1
*Vehicle swap goin into - 94 civic hatch
*Now for my questions,
1. What would i neeed to convert it to obd1? (dizzy, ecu, & injectors from a obd1
gsr)?
2. Or can i just use a jumper harness instead?

THANX!

robfrmny21

you can get a step down harness for the dizzy so you can use the obd 1 harness with obd 2 dizzy with it

vanste

i think you can leave the obd2 harness still on the engine and just plug right up to the harness at the strut tower, correct me if im wrong... and then just run a obd1 ecu a p72 or p28 well do...

nengx07

you need an obd1 alternator also.. plugs are different

420waipio

Are they pretty spendy, never heard of it.

So a p72 or p28 will plug right in were my ecu in my hatch is? or do i need a jumper?

Thanks i never knew that.

nengx07

yes the p72 from the 94-96 obd1 gsr ecu would fit right in.. also the p28 will fit right in too

94EG8

Use a '96 - '99 USDM GS-R/ITR engine harness, this allows you to retain the OBD2 distributor, alternator and injectors without cutting and splicing anything Use an OBD1 ECU and the whole thing is plug and play with the exception of wiring Vtec from the ECU to the shock tower plugs (if the car is a VX, Si or any '92 you can skip this step) and wiring the knock sensor and IABs (all models when using a P72, if using a P28 then you don't have to wire either)

420waipio

correct me if im wrong-will it matter if i use a p28 since its for a single cam vtec?

So ill be good since the obd2 swap i got came with the engine harness?

94EG8

If you get it chipped for a GS-R then no, it'll run the same as a stock P72 ECU except that you wont have functioning IABs, the P28 also doesn't look for a knock sensor.

As long as its a USDM harness, JDM harness are flipped around backwards and are usually cut somewhere.

NVturbo

If your OBD2 motor/tranny came complete with an engine harness, everything is plug & play. Just make sure you are using either an OBD1 chipped P28 or stock P72 ecu. Don't forget to run your wires for knock sensor, VTEC, etc.

420waipio

So is all i need is a obd1 ecu, no injectors, dizzy, or altenator? I got some info sayin that if i dont put the obd1 injectors on, it might melt wires or catch on fire, due to the resitor box on the obd1 and the obd2 dont have any resistor on it!

94EG8

Correct

OBD1 and OBD2 injectors work the same electrically, neither use a resistor box. OBD0 injectors use a resistor box that must be wired in when using OBD0 injectors. So no you don't have any risk of fire.

c1poweredeg

i just did the same exact swap. used an entire 00 gsr swap wit a chipped p28 with a gsr map. runs perfect, only problem i ran into was my tach not working so, i just ran a wire from the blue tach plug on the driverside shocktower harness to my cluster and it works perfect.my suggestion is to also upgrade to a better fuel pump and adjustable fuel preasure regulator. just my 2 cents

Redbone

like was said before just use an obd2 VTEC harness and obd2a or b, whichever your harness is, conversion harness to obd1 and run an obd1 ecu. Plug and play.

420waipio

ya i dont want to catch my hatch on fire that will suck!

Thanx i been thinkin of upgrading to a walbro fuel pump!

*Correct me if im wrong but the conversion harness is the one i can get from (rywire)?
*And would it be obd2 to obd1 conversion harness?

Redbone

it depends on what type of wiring harness you get. If its for an 96-98 civic it will be obd2a if its from a 99-00 it will be obd2b so make sure you figure that out and order the correct conversion harness when you do.

420waipio

Ok it came out of a 97 teg, so its obd2a, and is rywire a good place to order it from!
And tell them i need a obd2a to obd1 conversion harness?

Redbone

yup but you can find them for cheaper in a bunch of different places including the marketplace on here.

420waipio

i tried to get on and pm someone and they don't let me, probably cause i don't have enough privellages or sinyority!

portenio78

iTrader: (1)

Listen to 94eg8, he is exactly right.

ian_b16

no. just because hes is using the obd2 engine harness this does not change his interior harness. He will still have obd1 plugs for the ecu under the dash. There is no need for a conversion harness unless he wants to run an obd2 ecu.

420waipio

Thanks that's what i needed to hear, and i also appreciate everyone else helping me get the correct parts i need for my swap!
* just to be clear with what your saying - my plug thats under the dash thats plugged in the ecu in my car now will plug right into a obd1 p72 or p28?

ian_b16

you have a 94 civic? then yes any obd1 ecu will plug in

420waipio

Yes i do! Thanks for the info.

Redbone

obviously you did not read the first post. He has a complete obd2 gsr swap. OBD2!!! Therefore using an obd2 harness is far simpler than rewiring and changing out a bunch of parts you dont need to for an OBD1 setup, THEREFORE he uses an OBD2 harness and an OBD2a-OBD1 converrsion harness saving lots of money and rewiring/parts buying grief.