99-00 si motor in a 97 dx hatch

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hey i am going to help a friend do a swap. He has a 97 dx hatch and we are going to drop in a 99 si motor..... what all do i need to perform this swap......and what wiring modifications need to be done.......let me know
 
I am in the middle of this swap myself, except I am sway ATX to MTX.

You still have some decisions to make.

You want to run OBD2a OBD2b or OBD1? Depending on answer you will need the appropriate converter, unless you run OBD2a which your chassis and wiring harness are.

Personally I am running my 99 B16 with a 99 ECU and 97 EX harness with boomslang OBD2a to OBD2b conversion harness. Cost a little more, but I was looking for clean/OE swap.

You can rewire your existing harness or you can buy and EX harness for an OBD2a which your chassis is and modify it, which is less work than working with the DX harness.

Again, I chose the EX harness because it minimizes wiring work, and again for a clean/OE swap. Let me know if you want some details on wiring modifications. I did more than necessary, because I wanted to retain the use of as many OE wiring fasteners, clips and retainers as possilble, again for OE/clean swap and reliability.

AC, you need 94-95 DOHC Vtec AC bracket, if you which to use your existing Sanden AC compressor without discharging the system. I've heard 97 CRV work, no confirmation though. You can use the B16 Compressor but will need custom lines or perhaps Si ac lines.

PS, you need the Civic SI PS line from pump to "rack and pinion", unless you want to modify your existing.

You should have all the engine brackets you need, just use your OE rubber mounts.

Cooling, you need up radiator hose or custom.
 
hey i am doing the same thing...i did my homework.u will need b series mounts.i just bought them off i ht member for $230.u can get it for hansport,but it is like 400.and u got the whole swap(motor,tranny,ecu,shift linkage,alxes)??then u r set.the only i don't know it the wiring.i got a shop to do the swap for $500 and they will be done in one day
 
Unless the motor mounts are different on a hatch that a coupe (which I doubt they are), you can use your mounts, you just need the brackets that are on the Si engine or at least the rear one.
 
yes the mounts are already taken care of.....the wiring is my main concern..so if i use the dx harness i have wire up the knock and the vtec press and solenoid? i have the si harness also can this be used? I'm thinking about getting a 96-98 ex eng harness and getting the obd2a to obd2b adaptor harness.... any input?
 
you cannot use the 99 si harness. you're correct about your dx harness. i did the ex harness way when i did my swap (99si motor into a 96 dx coupe) but i used obd1 p28 ecu with obd1-2 jumper. weigh out the costs between your two options and pick the one you feel most comfortable with. which ecu will you be running? if its the 99si ecu, you'll need the obd2a-obd2b jumper.
 
thanks man, you know who sells these adapter harness's? i think i am going the obd2a-b route. if i decide to do like you did with the p28 will i have trouble passing emissions? holla
 
you will not pass emissions with a p28 in an obd2 car. jdmhondaparts.com makes the harnesses.
 
http://www.boomslang.us/products.htm has the wiring conversion harnesses too.

Nobody ever used the SI harness in that kind of swap, but it can be used. I was going to try and use the 99si harness in my 96 DX and simply repin the two connections that connect the engine harness to the chassis/dash harness. Would have been a super clean install, but I would have needed wiring diagrams for both applications to properly repin the connections. All bets were off when my "swap" motor I recieved had the ECU connectors cut off the harness. *shrug*
 
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