90 Crx Si With 90 B18a Swap

[allmotord16rex]

Hi guys, I have been searching the internet for awhile now as I prepare to do my 90-91 LS engine swap into my 90 CRX Si. I have a few questions and any help is appreciated. First, will the LS engine and ECU plug directly into my harness? Are there any wiring modifications that need to be done? I have heard some say that it does but i cant get a definite answer. I know that i need a mount kit, but which axles do i need? Thanks for the help guys.

 

[SleEPeR_CRX]

Hey man, i just did the exact same thing a month ago, any further questions let me know. now to answer ur questions, well #1 use ur Si harness, put all that on the LS motor then use the LS ecu and it will all plug in.next question no wiring mod's are needing to be done other than swapping over the Si harness to the LS.next question. yes u need a mountkit, for B-series into an EF. You should use stock B18a axels, take out the dust sheild so it spins, and ur good to go. ull see what im talking about when u get to that stage.

 

[allmotord16rex]

Thanks sleeper! So the LS engine harness will not just plug into the stock harness? I thought that you could just plug the LS engine into the SI harness. So I need to put all of the SI stuff on the LS engine? What about the distributor? Do you use the LS distributor? Does it plug directly into the SI harness? Thanks man!

 

[SleEPeR_CRX]

ya man, use the Si harness, everything from the LS plugs right in, even the distributor and the alt. once thats done its just simple, drop it in, bolt it down, connect some plugs and ur off mine was done in 3 days, with a few minor problems.
#1 i kept the stock rad hoses, they both blew in 2 days, delayed my start a bit.
#2 my CV wouldnt come out of my front hub, so i had to get a new 1 for $30.


The biggest tip i can say, is get new rad hoses when u do the swap use stock integra rad hoses.. get a new clutch and lighten ur flywheel b4 u do the swap. Right now i have to redo my clutch already, and its just a piss off. do it while the engine is out, alot easier. also, keep 300-400 bucks lieng around JUST incase something goes wrong. OOO also, u will need a new 91 integra clutch cable, the stock Si 1 doesnt reach anymore.

 

[allmotord16rex]

Im confused here. The LS motor plugs go into the SI harness, or do you have to put SI parts on the LS motor, such as the injectors.

 

[SleEPeR_CRX]

ya man, put the SI injectors and harness on the LS motor. Thats the only part u have to switch. then everything will just plug in.

 

[allmotord16rex]

Thanks sleeper! You're the man!

 

[allmotord16rex]

I got a question though, why does the B16A1 plug directly into the Si harness, besides the extra wires that need to be added? Why doesnt the B18A plug directly into the SI harness?

 

[SleEPeR_CRX]

who knows? are u doing a b16 swap? no? so what does it matter? i havent the slightest clue man, maybe someone else knows.

 

[allmotord16rex]

Sorry for all the questions sleeper. I just try to learn everything possible about honda swaps. I am actually contemplating a B16 swap, but the B18s low end torque and turbo possibilty is too much to look over. Thanks for all the help though. I have been looking at my engine bay and I think I have figured out what you are talking about. The wire that comes out of the harness from the firewall runs into the injectors and it is mounted on the fuel rail. It then runs to a connector on the drivers side of the car. Is this what needs to be put onto the LS motor. Sorry to keep bothering you with questions, but my friend is doing a B16 swap and didnt do proper research. Long story short a week and half later and that B16 still isnt even mounted yet.

 

[kango]

We just got done with the b18a swap into a CRX today ourselves. We actually kept the injectors on the Ls and the Si harness hooked up fine. There won't be any wires to add, however when you compare the Ls harness and the Si harness with each other, you'll notice a few extra plugs on the Ls harness. Don't worry about them. Just make sure all the Si plugs go in, and you're set to go. Also, I didn't do the wiring, but my friends did have to make some of the wiring longer or shorter, because not all the wires were the same length on the motors. If you call this modification of the wiring, then yes, it does have to be modified.

Hey, sleeper how'd you go about doing the shift linkage? We ended up cutting the one that was solid mounted on the Si tranny shorter and bolted it to the underbody, since the Ls engine doesn't have that mount. Then cut a section out of the actual shift linkage of the Ls shorter to fit. Is this anything like you did, or is there an easier way?

One more thing....when she bought the motor mount kit there were only 3 mounts. We were like, "wtf?" So we put the engine in leaving the front motor mount bracket in. If you are ABSOLUTELY sure you're going to do the swap, and you are ABSOLUTELY sure that you will never swap engines again, cut the front bracket out, or just bend it down. It is not used, it is a pain in the ass to work around and you don't end up using it. *shrugs* Good luck, and hope this helps

 

[allmotord16rex]

Thanks kango, I am glad you were able to hook the LS harness directly to the SI one. So the LS injectors hooked up to the SI harness? I thought that they would considering that the B16A1 does and all of these motor are OBD0. Thanks, someone has finally answered my question of whether or not the LS plugs directly into the SI harness. I think sleepers idea of putting the SI harness on the LS helps with the problem that you had with lengthening wires. Which way do you guys think is the easiest for the install? Thanks!

 

[MaaseyRacer]

dude just use the SI harness, no mods to it, use the LS injectors and everything, it is a pretty much plug and play swap... so you can throw out the LS harness.... or sell it...

 

[allmotord16rex]

Maasey Racer, Are you saying to do the swap like kango did? Do you mean just to plug everything from the LS into the Si harness? Just trying to clarify here. Thanks.

 

[allmotord16rex]

Also, did you guys that have done the swap use the stock hood. I have heard some say that it will not close with the B18. Anyone have any problems with there B18 scrubbing? Thanks.

 

[CapacitY]

Lol, okay, usually a person plugs the harnesses into the engine....not the engine into the harness. Like Maasey said, sell the Ls harness, throw it away, the actual Ls harness and wiring has NOTHING to do with the swap. Just COMPARE the Si harness to the Ls harness, and you'll find that some of the wires on the Si harness need to be lengthened or shortened. Once you figure out which wires on the SI HARNESS NEED TO BE LENGHTENED OR SHORTENED, THROW THE LS HARNESS OUT!

As far as the hood goes, my friend has a carbon fiber hood, but I believe the hoods are the same. After the engine was in I could've SWORE that the hood was not going to fit, but it did actually. Anybody else try the stock hood with success?

 

[SleEPeR_CRX]

Ok sorry i havent been on much lately, busy with provincial exams. Anyway ya man the best thing to do is ur the Si harness, dont worry about the LS 1. also, the shift linkage, go buy a stock Integra 90-93 shift linkage, hook up 1 side and measure how much it is to long, then go back, cut it and weld it back together. it works just as good as the hasport one and the best part is its free, just make sure u measure 3-4 times so ur positive its the right length. also i use the stock Si hood and it fits fine so u wont have any problems there. The front mount, just get an air chizzle and chizzle it off, u dont need it anymore b/c aftermarket mounts are made alot stronger than the stockers, u will notice this when u start the car up and sit in it for the 1st time, it will shake 100 times more than the stock grandma mounts.

 

[CapacitY]

Capacity = Kango

yeah, it's funny, but for some reason I LOVE the new rumble of her car, with the poly mounts. Good to hear from you again btw sleeper.

 

[dragoncrxls]

I am doing this swap, except I have a DX CRX. (more wiring) all I need is at least 2-14" Honda rims perferably with tires.

 

[allmotord16rex]

I was reading the FAQs on this forum and it said that the B18A ECU would not plug into the EF harness like the B16 ECU does? Is this true? I was under the impression that the B18A ECU would plug into the EF harness. Thanks.