I have a few questions about this swap. Right now I have a 92 Prelude Si with H23A of course, I am thinking about buying a JDM H22A long block , and ECU and throwing them in using the H23A tranny.

My first question , will the H22a exhaust manifold bolt up to my stock Si cat or do I need to get a cat from a 93-96 vtec?

Second ,should I need parts for this JDM H22a which will be a 92-95 OBD 1 , can I just purchase parts for our USDM 93-96 H22a for it ? Also if anyone knows of any parts that are different that I would have to get from Japan please feel free to list them.

Third question has to do with the differences between JDM H22 tranny and H23 tranny. I read on another post that one person said they could tell no difference at all , but another said that when shifting at wide open (I assume he meant redline which i think is 7600 rpm on J spec motor correct me if I am wrong on that one.) that the H23 tranny causes the motor to drop out of vtec , while the H22 tranny will allow it to stay in vtec. Also will I notice any difference in top speed with JDM H22 as opposed to H23 tranny.

Final question at what RPM does vtec engage on a JDM spec H22A with I believe it is the P13 ECU, and is it the same on the 93-96 USDM ecu ?

Thank you all in advance.

 

ttt

 

If you want some good imput, contact username 'clendaniel'. He has done it, but he is FI, in my eyes thats the only reason why one would do that swap (at least that I can think of).

 

I have a similar swap. H22a4 w/H23 tranny. Honestly, there isn't that much of a difference when compared to a straight H22 swap. With an 8lb flywheel, good clutch, and shifting @ 7800...it only drops out of VTEC for a split second. But with the flywheel, this thing loves to rev. As for top speed, the extra gearing should give it a little more top speed. I've never tried it. (And you don't need to top it out on the streets anyways)

For the swap itself, you'll need to convert to an external distributor. (JDM = internal dist) And you'll need to take the car to the muffler shop to customize the downpipe to your cat. Besides the different flange, it's a bit shorter...so they have to extend it a little.

And I would go with an USDM P13. The JDM ecu has a speed limiter. VTEC *should* kick in around 5000.

 

I have just completed a JDM H22a swap into my 94 Si. There were a few things I had to switch around in order for it to work. I had to use the fuel rail from my H23 because the fuel line is opposite side in the JDM cars. I installed a header to take care of the exhaust problem. My stock h23 "A" pipe was the correct length but the flange on the manifold is much different. Just order a header for a 92-96 H22a USDM it will work fine. I also used the distributor from the H23 since the JDM uses an internal coil. I had to use the map sensor from the H23 since it's attached to the firewall but you probably can extend that harness to the map sensor on the h22a. I used my h23 tranny and installed a clutchmaster stage 2 kit. The JDM vtec soleniod doesn't have a pressure switch on it. It has a 10mm oil plug that has to be removed from the solenoid and a pressure switch installed. The wiring is the same with the exception of the one green/white wire for the vtec that on certain 4th gen preludes is already wired from the ecu to the shock tower. So just get two male vtec plugs from any vtec harness and wire from the shock tower to the solenoid. There is a 10 pin connection with one pin that has a rubber plug in it. That is the pressure switch wire. The second pin on the pressure switch is ground. I grounded mine right beside the vtec solenoid.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JBB194 &raquo;</TD></TR><TR><TD CLASS="quote">I am thinking about buying a JDM H22A long block , and ECU and throwing them in using the H23A tranny. </TD></TR></TABLE>

correct me if im wrong doesn't a "longblock" include trans. and a shortblock is the engine only? i've seen a couple of people on here refer to the engine as a longblock. so what is the correct term?

 

I have the exact swap in one of my preludes. Things you need when just putting in a longblock are exhaustmanifold with downpipe yes it bolts directly to the cat. us the h23wiring harmess then run a wire for vtec off the ecu or vafc. I stillhave power steering, ac, you can also use the h23 crankpully and belt (ie if you already have aem pulley's or something along those lines). P13 usmd ecu is fine to use actually better because jdm P13 have speed cut as 120mph .. As far as the tranny goes they h23 tranny has longer gears tachs out longer it's all in the person i guess i find it helps when running other ludes there shifting into a gear when you stillhave about 600rpm left before you have to shift . I think thats shoudl do

 

yep your wrong longblock is head and block short block is just a block

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by md23vtec &raquo;</TD></TR><TR><TD CLASS="quote">yep your wrong longblock is head and block short block is just a block </TD></TR></TABLE>

word

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by md23vtec &raquo;</TD></TR><TR><TD CLASS="quote">As far as the tranny goes they h23 tranny has longer gears tachs out longer it's all in the person i guess i find it helps when running other ludes there shifting into a gear when you stillhave about 600rpm left before you have to shift . I think thats shoudl do </TD></TR></TABLE>

so an h22a with an h23a tranny tach out later than the h22a tranny?

also, when someone said that the h23a tranny will drop out of vtec, does that mean its not in vtec anymore when you shift?

sorry, im not too smart about h series.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by underdestruction &raquo;</TD></TR><TR><TD CLASS="quote"> The JDM vtec soleniod doesn't have a pressure switch on it. It has a 10mm oil plug that has to be removed from the solenoid and a pressure switch i</TD></TR></TABLE>
what does that mean all vtec motors have a pressure switch, its a completely diff spot on the motor, the oil pressure sensor has light blue wire and a brown wire......on the swap, theres the vtec solenoid and then theres the oil pressure switch...im not quite sure what your talking about...peace

 

mine doesn't drop out of vtec and i have rev limit set to 7000