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engine swap H22A8 to H22A7, H22A JDM etc.
Posted: Sun May 03, 2015 12:46 am
by stinkypaul
can someone offer me advice please on an engine swap from an H22A8 to potentially an H22A JDM (both 5th gen)? as I'm new to prelude I'm unsure about any issues with the ecu, obd1 vs obd2 and knock sensor.
Reason being, I'm looking to replace the dead H22a8 motor in mine and H22a8s seem to be scarce. H22A7s are available (but pricey), there is a H22A jdm available. Maybe even a H22a5.
Are any of these plug and play or will there be some swapping of loom, injectors etc?
I'm a bit confused?
Posted: Sun May 03, 2015 9:48 am
by wurlycorner
If it's from a 5g, it should be just plug and play.
Not sure how well an a8 ecu would work with a5 engine though?
@Donald has an a8 engine available
Posted: Sun May 03, 2015 10:06 am
by Donald
Swapping the H22A8 for an H22A is a downgrade in potential btw. 11:1 comp to 10.6:1.
The only engines you're gonna find that won't be a downgrade are A7s, a TypeS H22A (won't fit) and an S-Spec H22A (good luck finding one).
As wurly says, I have an A8.
Posted: Sun May 03, 2015 10:08 am
by Donald
wurlycorner wrote:Not sure how well an a8 ecu would work with a5 engine though?
Will probably throw some light as the A8 has a knock sensor

Posted: Sun May 03, 2015 11:46 am
by wurlycorner
I was also wondering whether the fact it's different compression and power output etc might mean the map is a bit off?
Posted: Sun May 03, 2015 2:46 pm
by Donald
Maybe, its only a 12bhp difference and considering the amount of people that install mods without mapping or run a chip they don't need... probably won't be noticeable

Posted: Sun May 03, 2015 3:21 pm
by stinkypaul
Looking on Wikipedia it shows (jdm) sir, sir s spec, and type s.
So is it only the s spec that goes straight in? (as I think I've found one). Why won't the others fit?
Posted: Sun May 03, 2015 4:34 pm
by Donald
JDM SiR engine will fit but they are not high comp like the A8/S-Spec/TypeS. 197bhp but 10.6:1. TypeS something about the block being different, plus you'd spend more money than is sensible on blanking off the ATTS stuff. TBH I'd be pretty surprised if you've found a genuine S-Spec engine... they make TypeS's seem common.
Posted: Sun May 03, 2015 4:43 pm
by stinkypaul
Trying to find out which one it is. If it's a type s I'll leave it, I can see there's the difference at the back of the block.
H22a5 or jdm sir, sir s spec. Will suit me as I would like to get the car running again at low cost. I can live with bit less power.
Doyou know if the jdm sir is obd1 or obd2? The donor car is a jdm 1997 but someone has stuck a type r badge on it so not sure what model it is. It has a sunroof and I don't think the type s had a sunroof?
Posted: Sun May 03, 2015 4:53 pm
by 4thgenphil
Have you spoke to donald, easiet thing to do would a be a like for like swap imo.
That way you have less hassle swapping bits over etc like ecu amd all that goes with that