Jump to content

engine rebuild with 98 parts in 96?

Recommended Posts

I bent valve so i got new heads from a 96 block but the guy also threw in a 98 short block that overheated so i start ripn it apart but want to know what can i use from the 98 cause the pistons are different and the crank is alil different but bearing all look the same. Any ideas i looked on rock auto the crank part number comes back the same but would the pistons work
Link to comment
Share on other sites

the only real difference between 96 and 98 ej25D engines is the valve lash adjusters.

96 is hydraulic,


98 is bucket and shim. (don't mix up the shims.)

and the valves should be adjusted if you use these heads.


the 96 outback ej25 recommended mid-grade fuel.

the 98 did not.

i do not know if this was based on the valve lash adjusters or not.

i kind of doubt it.


i would stick with 96 heads if you have a 96..


what is wrong with your engine?

not many folks split a subaru block, remove the crank.

it is usually cheaper to find a replacement .

Link to comment
Share on other sites

If you've gone this route. You have some important things to deal with.

Generally it is not cost or time efficient to rebuild an EJ block.

If you still wish to go ahead, you must first download the FSM.

Your engine spec pages will give you good info. Then the engine section.

The pistons are marked A or B. You need to match these to the block.

Your biggest issue will be the crank. It is best to have it machined so that the journals are equal.

The crank will have a group of 5 letters from A to D. eg. BBCCD then a group of 4 letters usually I and Z eg IIZI.

You need a good micrometer. The crank letters indicate that the journals are of different tolerances. A is std, B is .03, C is .05 and D is .25. This prevents you from buying just a set of bearings. Subaru does sell crank bearings individually, but you must be sure of the sizes. They won't be in stock and will take a while to get.

Then you have to deal with the rod journals! These are only available in sets.

Again best to leave it alone.

Since all you have are bent valves, Just replace the heads, resurface them ,adjust them and use Subaru or SixStar gaskets.



Link to comment
Share on other sites

You can swap the internals. Both the 96 and 98 have the #3 thrust position. I would replace the piston rings. The only possible issue is a mismatch of the A or B from one block to the other. Then you would have to replace the piston ONLY to match. I don't know of any adverse effect of different piston dish tops.



Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...

Important Information

Terms of Use