Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Head swap

Featured Replies

Can I put 1.8L Heads on a 2.2L motor? Is there an adapter? Is it even possable?

depends what 1.8 you're talking about.

 

 

all EJ series heads are interchangeable. so if you're talking about putting EJ18 heads on an EJ22, yes, it definitely will work. and it'll bump your compression up a bit (start running premium gas!).

 

if you're talking about EA-series 1.8s.....no. no way.

  • Author

both are ej motors. What will the compression be if I swap and am I going to need to swap the intake manifold? Is there anything I need to know

Don't know what the comp. will be, but the manifolds will swap between the 1.8 and 2.2 so there should be no problems with that. You can change the comp. ratio some by picking the right EJ gasket.

 

GD

whay do you want EJ18 heads put on EJ22 block

 

just put EJ18 distributor on EJ22 head

whay do you want EJ18 heads put on EJ22 block

 

just put EJ18 distributor on EJ22 head

 

The US didn't get carbed EJ's - no EJ distributors of any kind here.

 

GD

The US didn't get carbed EJ's - no EJ distributors of any kind here.

 

GD

really weird that the US versions are so much different then other specs...and this is a prime example

  • Author

I have a bad valve on my 2.2 but have two 1.8's that are good.

How would changing the gasket help with it?

if it lowers the comp. that means the displacement is different? would it lower it to the 2.0 comp.?

Why would I change the distrubuter?

ignore the distributer comment, not applicable.

 

technically, yea, the smaller quench volume of the 1.8 heads will change your displacement, but only by about 8ccs. Also, I think standard EJ22s already use the thicker headgasket, so you could only increase the compression ratio by changing the gasket.

 

stock 2.2 compression ratio is 9.5:1. I think 1.8 heads brings it to like 10.5 or so. should make for some sweet torque, but you'll need to run premium gas to prevent detonation.

How does the chamber volume change the swept volume? (i.e. displacement)

depends what 1.8 you're talking about.

 

 

all EJ series heads are interchangeable. so if you're talking about putting EJ18 heads on an EJ22, yes, it definitely will work. and it'll bump your compression up a bit (start running premium gas!).

 

if you're talking about EA-series 1.8s.....no. no way.

 

I've been wondering that for quite a while. So I could theoretically put STI heads & intake on a EJ22T SOHC motor?

I've been wondering that for quite a while. So I could theoretically put STI heads & intake on a EJ22T SOHC motor?

 

easy. as far as the head-to-block mating, yes.

 

 

as a general rule, intake mani has to match the heads (there are exceptions, in this case, 1.8 and 2.2 are interchangeable). also as a general rule, heads from larger-displacement engines have a larger quench volume, and vice versa. so swapping around will effect compression. also, using heads for a much larger bore can cause issues with the headgasket mating surface (I have heard of issues with N/A 25D heads on 18s to be specific).

 

 

 

capn_r. *my understanding is* the quench volume of the heads *technically* effects the volume of the overall combustion chamber. but it's only a couple ccs each, so it's not enough to substantially effect the displacement (for example, a 2.2l is 2212 ccs, with 1.8 heads, it's probably 2204). but at TDC, it's a substantial change, so noticeably effects the compression ratio.

Not trying to threadjack or beat a deadhorse here but, are there any other differences between the ej18/22 heads? Valve sizes/porting, or cam profiles? Just curious if there's some optimum combo of head/cam/gasket to run on a na-ej22. Thanks, Spencer

valves and such are comparable to 2.2 stuff. you would gain some grunt from the compression bump....but that's about it. you'd be better off throwing a 2.5 shortblock under the 2.2 heads.

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.