Is there a problem with using a rotor housing that was originally on the front rotor to be used for the rear of a different engine?

Thanks.
- Cooper Lacy

 

if you plan on passing emissions, then yes.

 

So is the only difference the EGR passages below the exhaust ports?

 

yes

 

The housings are identical, even down to the EGR passages, I believe.

The one small problem is that the triangle assist piece on the apex seal tends to "groove" one side of the housing, so that might be a concern for you.


-Ted

 

nope, at least on s4 models the egr passages are different. I didn't believe it at first till I sat down and compared the two. Sure enough I found it. Its a small difference, but its there.

 

Is there any problem with turning the apex seal around so the triangular corner chip is facing the other direction. I would be using new 2-piece apex seals.

 

Besides being more difficult to assemble.

 

Cooper Lacy! My brother's friend from RHIT! What's cracking?

 

s5 and up will also block off the passage from the air control valve to the exhaust port if you swap them and dont drill a new hole

mike

 

Who worries about emissions?
Yeah, I remember something about some weird difference between them, but it's not something I worry about. Thanx for clearing all that up.


-Ted

 

I question then, how can you tell the difference between the front and rear rotor housing?

 

right under the licensing on each housing there should be a stamp. F for front, R for rear.

 

Are you talking s5 to s5 or s5 to s4?