Hi guys I’m new here. I have a 91 civic hatchback base model ef. I’m getting prepared to do a b16a swap soon and I’m trying to get all the info/parts together before I get going. I’ve been reading as many forum topics I can find and I still have a few questions. The guy I’m getting the engine from also has a wiring harness to go with it but not sure what car it came out of just know it works with the engine. I know it’s difficult to use a different harness than the one that came with the car but due to mine being basically destroyed from the previous owner I would like to replace as much of the wiring as I can. My question is would it be better to:
1. try to save the harness I already have or
2. use the harness I’m getting or
3. Just buy a harness online that is already set up for mpfi and vtec and made to fit my car.
Again, I’m not sure what car the harness I’m getting came out of but it’s coming with the engine so might as well grab it. Also if the harness doesn’t match up is there a diagram somewhere I can look up to see if I can re-pin the connectors for the harness I’m getting? Because I know they won’t just plug and play from different cars and I would have to re-pin the connectors where it plugs in to the interior harness and such.
I’m sure this has been answered but I’m struggling to find links as most of the links i find in this forum are old and broken.
thanks in advance!

 

If you have read more than two write ups on b16 swaps you would have notice but you haven’t so you will notice eventually notice That almost everyone modifies the original harness to work with the swap

If he’s giving you a free harness then free is free
unless he means to troll you the harness he plans to give you is probably setup for the swap

if it’s set up for the b swap then it doesn’t matter what car it originally came from

 

Your best bet is to modify the STD harness. If you can't find the writeup you need, you should get a copy of the factory service manual (made by Helm) and that has all the wiring diagrams with colors and pinouts. You could also do it the slow way and test the harness with a meter to figure out what goes where. The only alternative is to buy a new harness that is made for your swap. I've had good luck with Monotech and they are fairly affordable.

 

That’s what I was afraid of. Thanks for info man. Will definitely check them out. Rywire makes a harness also but is like 450 and some change.

 

Here are pics of my bay with d15 still in it. This is what I’m working with 😂




last one is under dash. Going to end up replacing all 3 harnesses eventually. Someone did a number to the whole car.

 

Looks like Monotech has one on eBay now for $290. Rewiring the harness isn't too bad, it just takes a little time.

 

don't replace what isn't broken, all I see is crappy ran speaker system, no hacks or splices on the underdash.

if all lights work, all systems function correctly then just modify the stock engine harness for about $30-60 yourself.

if you do the conversion the lazyiest way you are adding 6 wires, 4 to injectors, 2 to the distributor.