2.7 exhaust in a 5.2 car.. Possible?

Is it possible to stick a 2.7 style exhaust in a 5.2 car with a 5.2 engine cradle..?
If not which part of the exhaust would 'foul' and have no clearance with the 5.2 engine cradle..
.

 

Nothing would foul. The only difference between nearly every single exhaust on the market for a 2.7 or 5.2 is whether or not it has the thermocouple bung welded for the bypass. 2.7 has no provision for this but the 5.2 motronic does in most markets, including AUDM cars. So if you have a 5.2 and want to use a 2.7 muffler you will need to have the exhaust modified to include a bung to install the bypass thermocouple.

 

Do you mean the whole exhaust system from manifold (extractors) to exhaust tips?

Do the 2.7 exhausts have holes for the post-cat O2 sensors, Elliott?

 

No but when he is talking exhaust I’m thinking back box. If he is talking catalysts and headers that’s another story. Not sure why you’d want to do that, maybe OP can elaborate.

 

The 2.7 system by my reckoning seems superior to the 5.2 as the flow paths are more streamlined.. especially in the area of the Y pipe.

So what I am referring to is a hybrid swap of a 2.7 (headers & Y pipe,) into a 5.2 car with 5.2 lower cats and muffler )

Is this possible..? assuming bypass thermocouple bung is welded in to my existing 5.2 muffler(which it is)..?

In other words will the 2.7 headers and Y pipe bolt up to my 5.2 muffler & 5.2 main cats?

 

Since the headers to y-pie is 2.7, you should be okay to bolt on the cats and muffler since they can be adjusted for position.

I don't believe a 2.7 Y-pipe will fit a 5.2 header and a 5.2 Y-pipe fit a 2.7 Header. From my past experiences, there seemed to be three unique exhaust systems throughout the 355 production with the most noticeably 2.7 vs 5.2. I forget if there were two different 5.2 systems of 2 different 2.7 systems.

 

What is the ultimate goal?

 

The different Y pipes do not interchange.

 

Let me rephrase the question..

Assuming one has an aftermarket ECU and thus can do away with the issues of rear O2 sensors and thermocouples

Is it possible to put a complete 2.7 exhaust system ( headers/Y pipe/main cats and muffler) into a 5.2 car using the 5.2 engine cradle.
Will it physically fit or foul on the 5.2 engine cradle..?

Ive heard that there are differences in the engine cradles between the 2.7 and the 5.2 such that the Y pipes can't be swapped over..
Something to do with differences in the shape/location of a 'horizontal bar' in the engine cradle in the area of the Y pipe..

 

Maybe no help but I'll share my thoughts.

I do not know for sure but-to me- It seems the 2.7 and 5.2 cradle are dimensionally the same as far as exhaust clearance is concerned. Seems there may be some difference to something as the part number changed.

Another way of looking at it....

If you're the type capable of fitting an aftermarket ecu, I would also follow your thinking, for reasons you stated and acquire/fit 2.7 headers and y-pipe.

 

Yes.

Y-pipes are routed differently but the frame is dimensionally the same.

If you have an F1 system, there may be some transmission stuff that does not work with the 2.7 y-pipes.

Also note:: the 2.7 y-pipe interferes with the common air port between the filter boxes and the Helmholtz resonators.

 

Agreed. You would need to remove the small welded brackets for those attachment points and reconfigure.

Still curious about what the goal is? A different sound? Performance? Looks?