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Discussion Starter · #1 · (Edited)
Wassup peeps! Anyway, just like the title says, will a 98 usdm h22a4 head fit on a 96 h22a jdm block? I have a complete 96 jdm h22a but it has bent valves. So im trying to swap an extra 98 usdm head that i have, which is fully built with Crower cams, Webcam dual valve springs, Webcam titanium retainers SI oversized valves w/ 5 angle valve job and a full on port and polish. i know both are OBD-2, correct me if im wrong, but i also notice that the distributor connection on the jdm head has a different connector compared to the usdm head, im assuming both have different wiring harnesses. So this leads to my next question. Would i be having problems with any sensors or wiring harness connections to the jdm block if im using a usdm wire harness? Please help, i wanna get this project started asap! Thanks!
 

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Discussion Starter · #2 ·
I think the jdm engine and the usdm head are not compatible and here is why, first, the head is made for a open deck block, not a closed deck; second, the udsm head has no crank position sensor(as it is in the oil pump on the 97+) on the obd1 jdm engine the cps is in the dizzy(which you wont have if you have a a4 head), next up is the hook ups, if you have an a4 head then i am sure you are gonna either need your 5th gen harness(cuz the connections are different form obd1 to obd2, ei: knock sensor,vtec solenoid, injector...).
If the a4 head fits(which i am not to sure) then you will have to switch over the block peripherals; alternator, oil pump(with 5 gen, so you have cps), water pump and balance shaft cogs. If i was you i would buy a set of new valves and fix the other head.
i thought only the 92-95 jdm/usdm motors were closed decked and of OBD1, while the 96+ jdm/usdm motors were open deck and of OBD2 decent. Someone correct me if im wrong. but hey, thank you for the info for it is greatly appreciated. LOL your the only one who replied but with very knowledgeable information. thought me something new.
 

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Bump for this. I have the same question. Currently running h22a4 head with h22a block. Car runs but trying to figure out what the heck the previous owners did as the car has wiring issues and we would like to re-wire it.
 
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