I am looking into investing in a Blue top H23A for my 91 EX. I know that it will not be an easy "plug n play" swap, but I've been told that a lot of what's in my EX right now would be compatible and there are some parts that will need replacing/modifying. Can anyone guide me in the right direction for a guide of any sort? Maybe even share your experiences/pics if you have a similar swap. Questions I have are:

Will I need a Prelude or Cat converter or will it even matter?
Axles are new right now, but will I need to change those?
Clutch is still good, so can I get away with sticking with my current clutch or change them too, since my current tranny is compatible with the h22/h23?
Im not gonna boost or anything, but what's the best ecu to use for my setup?

So much to do yet lost like Dorothy in the land of Oz...

 

https://honda-tech.com/forums/honda-accord-1990-2002-2/1990-2002-accord-faq-1664547/

 

Just get an h22a obd1(this is important) intake manifold and an obd1 h22 distributor and buy a vtec iab and knock sensor wiring kit. This is really the major issues facing you. Yes, you can use your current tranny. You will run out of vtec in the lower gears when redlining but it will otherwise work great and save you gas when cruising since rpms will be slightly lower.

 

I just swapped an F series tranny out, and an H series tranny in. I can tell you full well that the F series trannys rev the car alot lower. I feel like i'm using a type R tranny compared to the F...

 

Is this the H23a1 non vtec or the H23a jdm vtec engine, thats makes a big differance on what you have to do.

 

the black top is the h23a1 the blue top is the h23a vtec..he said blue top

 

Ah true didn't even realize that hehe, I think it's possible to use your existing distributor on the h23 as long as you use the f22a internal parts. Your distributor on your f22a is an internal coil design and if your bought a usdm h22 distributor it is an external design this makes a difference in wiring, keep that in mind aswell.

 

Nah, only the tranny, axles, mounts, and majority of existing wiring will stay. Everything else will be changed like longblock, clutch, and ecu. Some re-wiring may have to be done too. I'm not trying to be all about race, just a better engine to replace my current engine which may be coming to its temporary retirement.

 

Yup didn't mention performance, just trying to save you some time and headaches from buying the wrong distributor for your harness, H23a Vtec is obd2 and a north american h22a1 has an external coil which has a different connection than your 91 ex wiring harness if you use the case from the h23a distributor and the internals from your stock f22a4 distributor and you will have the exact same thing as a jdm h22a has which plugs directly into your harness with no need to hack/rewire anything which will be less possible problems with your swap. I just finished swapping a jdm h22a into my 90 exr which is the canadian equivalent of the us ex, it was simple and painless. If you can run 4 wires and take your old engine out, you'll have no problems with your swap. I had to retain the h2u5 stock f tranny so if there is no tranny with your swap the accord one will work aswell. It's just got taller gears and drops down to 4650 between 1st and 2nd, which means no vtec for about a second or two. Definitly faster than the stock f but not as fast as and H tranny on it too.

Here is a short vid of the h with f tranny.

 

^ Nice