99 legacy outback 2.5 dohc was swaped out for a 99 2.2 which is gen 2 and needs gen 2 intake but idle air controlers are different.

How hard would swapping the harness and ecm be? Would that work?

Nope. Doesn't work.

 

You can put the 2.5 heads on the 2.2 block.

Or just get another 90-98 2.2. Need a 95-98 manifold and wire harness. Need a manifold with EGR if you need to pass emissions inspection.

Nope. Doesn't work.

You can put the 2.5 heads on the 2.2 block.

Or just get another 90-98 2.2. Need a 95-98 manifold and wire harness. Need a manifold with EGR if you need to pass emissions inspection.

can I swap to gen 1 2.2 heads and intake with egr. Any valve clearance issues .

works fine to put the phase 1 2.2 heads on the newer 2.2. Should be same process as the typical frankenmotor on here.

Edited February 6, 201610 yr by AdventureSubaru

Nope. Doesn't work.

You can put the 2.5 heads on the 2.2 block.

Or just get another 90-98 2.2. Need a 95-98 manifold and wire harness. Need a manifold with EGR if you need to pass emissions inspection.

Will putting 2.5 heads on the 2.2 still make it subject to head gasket failure.

yep. Guys report better reliability off of the turbo gaskets. Do a search for the part number.

 

The other question is the reliability of the 2.5 heads to begin with. If a rod/rod bearing went out it's often overheating or oil starvation that causes it. It can stress other things.

 

I'm partial to the straight 2.2 swaps. They were way more forgiving and very reliable.

Once replaced properly, the 2.5 dohc engine is reliable. As long as the block was not continually overheated, putting undue stress on the bearings.

 

2.5 heads on a 2.2 block just requires the special Cometic gasket that matches the cooling ports.

 

O.