1966 Imperial single exhaust muffler size

[patinated_imperial]

Could any one on the forum help me with the dimensions and layout of the original muffler for this car?

I believe my exhaust is mostly original, but someone changed the muffler, to what I believe is a wrong one (too long). In the process, they managed to bend the pipe that goes over the axle, so it has almost collapsed. Also to avoid the muffler hitting the suspension, it hangs too low causing the pipe to rub against the cable for the parking brake.

I would like to find a generic muffler as close to the OE as possible. The pipes are still in good condition - plenty of steel left. Except for the collapsed part over the axle of course.

Also: Is it correct the pipe size reduces in the muffler. I.e. 2.5" going in and 2" or 2.25" going out?

Any pointers to where my exhaust deviates from the original much appreciated!

 

[413]

Looks like idiots worked on your car, they added 4-5” of adapters at the front, another 2” added at the rear, then they scrunched the pipe at the rear.
If you remove all that garbage from the End of the head pipe to the start of the tailpipe there is plenty for Odom for a muffler.

It is quite common to have a larger inlet 2.5” and smaller outlet 2.25” on stock BB Chrysler mufflers.

my 1962 383 chrysler has 2.5” inlet 2” outlet.

 

[patinated_imperial]

Looks like idiots worked on your car, they added 4-5” of adapters at the front, another 2” added at the rear, then they scrunched the pipe at the rear.
If you remove all that garbage from the End of the head pipe to the start of the tailpipe there is plenty for Odom for a muffler.

It is quite common to have a larger inlet and smaller outlet on stock BB Chrysler mufflers.

Agreed about the idiots . Luckily the rest of the car seems quite untouched.
Good point on the room taken by the adapters. Unfortunately the adapters are welded on with something best described as long tacks. I hope the end of the head pipe is salvageable.

 

[CBODY67]

The normal C-body muffler is an oval, with offset inlet of 2.25" and center exit of 2.0", 26" case length. That case length works from '65 - '73 model years. The ONE exception, according to the old Walker Exhaust catalog, is the 1969 Polara 440/375, which came with the Street Hemi mufflers as standard, that ONE model year/engine combination. Which also coincides with the Fastest Mopar Police Car that year/engine combination! Right at 150mph, stock. A title that was held until the Camaro IROC-Z type police vehicles came out . . . with the Camaro only a few mph faster. The normal C-body case length was on both C-body and C-body-similar Imperials, except fo rthe '69 Polara 440/375.. The '64-'66 Imperials, I believe, used a different muffler, more round than oval, possibly with center inlet/center outlets? Probably 2.25" inlets and 2.0" outlets, too?

Mu old Walker Exhaust paper catalog is archived somewhere. The current NAPA website only does C-bodies in '66, not Imperials, unfortunately. The genuine Walker Exhaust website only has the "muscle car" B-body listings in those years.

Might need to contact Waldron's and get some factory-correct parts to make things right again. Probably will need from the center fall-joint connection rearward and possibly new hangers?

Just some thoughts,
CBODY67

 

[patinated_imperial]

Thanks a lot for that data CBODY67! It will give me something to work from.
It makes sense to me if the imperial muffler was more round in shape. There is not a lot of width available. But seeing pictures of mostly dual exhaust online; most people have the oval mufflers as well.
I found some original bend sheets from Huth Manufacturing on the imperial club website. It suggests the pipes were 2.5" before the muffler and 2.25" after.

I would love to get parts from waldrons, but including shipping to Denmark, I think it will have to wait a few years before I can prioritize that.

 

[CBODY67]

I understand the shipping situation. There should be a diagram of the factory dual and single exhaust systems in the 1966FSM. Would not show you the dimensions of the muffler, but how it looks. The inlet pipe should match the diameter of the pipe before that ball joint coupling, I suspect.

I need to look at Waldron's website to see if they have a catalog with illustrations and data.

Enjoy!
CBODY67

 

[patinated_imperial]

Just to finish my own thread:
I found a universal Walker muffler width roughly the right outer dimensions and with correct offset Ø2,5" inlet and center Ø2,25" outlet. I think this muffler is a little wider than the original, as it had to sit a little lower than I would have preferred in order to clear a bracket on the frame.
I made new rubber straps for the center hanger using the sidewall from a truck trailer suspension air-bag.
Just as CBODY67 suggested, the FSM diagram of the exhaust was a good help.
The collapsed bend was cut out and replaced with a universal 2,25" 90° bend, which has a larger radius than the OE, I think.
There is no picture, but the exhaust clears the parking brake cable now

 

[Tireguy]

Good job