SOHC EJ25 and EJ22 inlet question
- El_Freddo
- Master Member
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- Joined: Tue Oct 04, 2005 10:00 am
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SOHC EJ25 and EJ22 inlet question
G'day all subi nuts.
Got a question that I hope someone knows the answer to:
Is it possible to take a 2005 EJ25 SOHC long block and a gen1 or gen2 EJ22 inlet manifold and bolt the two directly together?
The EJ25 is apparently from an Impreza and does not have the active cams system on it.
The aim is to use the EJ22 intake, loom and ecu to run the EJ25 without all the security gear of the 2005 system as getting a matching set and a wiring diagram has been difficult.
The only other thing to discuss is the EJ22 ECU running the EJ25 block without issues. The only other mod that would be needed is the crank and cam angle timing marks swapped (timing gears etc)
I'm asking these questions to help a fella out with a project. I went to view his Subaru but it wasn't what I was expecting and be was kinda sitting on the fence anyway with the sale.
Any help would be great.
Cheers
Bennie
Got a question that I hope someone knows the answer to:
Is it possible to take a 2005 EJ25 SOHC long block and a gen1 or gen2 EJ22 inlet manifold and bolt the two directly together?
The EJ25 is apparently from an Impreza and does not have the active cams system on it.
The aim is to use the EJ22 intake, loom and ecu to run the EJ25 without all the security gear of the 2005 system as getting a matching set and a wiring diagram has been difficult.
The only other thing to discuss is the EJ22 ECU running the EJ25 block without issues. The only other mod that would be needed is the crank and cam angle timing marks swapped (timing gears etc)
I'm asking these questions to help a fella out with a project. I went to view his Subaru but it wasn't what I was expecting and be was kinda sitting on the fence anyway with the sale.
Any help would be great.
Cheers
Bennie
Hi there mate. My race car is running the same motor. The intake manifold don't match up. The manifold is too narrow and the ports are smaller. I've gone with an 04 manifold that doesn't have the electric throttle and modified to fit IVC and throttle body.
I've modified the 22 harness too work with the 25 and still running standard 22 ECU without a fault.
I've modified the 22 harness too work with the 25 and still running standard 22 ECU without a fault.
[SIGPIC][/SIGPIC]88 Subaru Brumby (Currently being restored.
84 brumby 2 inch Lift(very rough, Big tires)
Landrover series two. 186 holden banger under hood.

Landrover series two. 186 holden banger under hood.
- TOONGA
- Elder Member
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Ok I was thinking EJ22 heads EJ25 block sorry
Yes it is very possible, but the head gaskets are the problem. Cometic make a gasket that is quite literally called the conversion gasket or the hybrid gasket part number H1631spk051s.
http://www.ultimatesubaru.org/forum/top ... or-gasket/
I know RSR bought a few sets a while ago and that they are still available from the USA.
TOONGA
Yes it is very possible, but the head gaskets are the problem. Cometic make a gasket that is quite literally called the conversion gasket or the hybrid gasket part number H1631spk051s.
http://www.ultimatesubaru.org/forum/top ... or-gasket/
I know RSR bought a few sets a while ago and that they are still available from the USA.
TOONGA
Ah I got ya, personally I wouldn't bother. The 25 heads flow better and don't run hydraulic lash adjusters and you don't have to open up the engine.
[SIGPIC][/SIGPIC]88 Subaru Brumby (Currently being restored.
84 brumby 2 inch Lift(very rough, Big tires)
Landrover series two. 186 holden banger under hood.

Landrover series two. 186 holden banger under hood.
- El_Freddo
- Master Member
- Posts: 12626
- Joined: Tue Oct 04, 2005 10:00 am
- Location: Bridgewater Vic
- Contact:
Nah just the EJ22 intake onto the EJ25 heads...
Good to know bboy! Did you swap the timing gear on the crank and cam shaft to match the ECU's requirements?
And how hard was it sourcing the 2004 intake manifold? This intake had provisions for a throttle cable so maybe it's 2004 build with a 2005 model year sale date...
Jules, good to know the head gasket part number anyway!
Cheers
Bennie
Good to know bboy! Did you swap the timing gear on the crank and cam shaft to match the ECU's requirements?
And how hard was it sourcing the 2004 intake manifold? This intake had provisions for a throttle cable so maybe it's 2004 build with a 2005 model year sale date...
Jules, good to know the head gasket part number anyway!
Cheers
Bennie
yep swapped over the timing gears. The intake was easy to get. I swapped over the injector plug bodies to suit the ej25 injectors. I can take pictures if you need.
[SIGPIC][/SIGPIC]88 Subaru Brumby (Currently being restored.
84 brumby 2 inch Lift(very rough, Big tires)
Landrover series two. 186 holden banger under hood.

Landrover series two. 186 holden banger under hood.