I have tried to search the site...but we all know how that goes. So, I thought I would just ask. I am wondering what the longest Dynomax Ultra Flo Welded muffler I can fit in a Cuda is? I think they make a 14", 20" and 24" case length. I will be doing 3" pipe and attempting to mount them in the stock muffler location.

Thanks in advance!

Get under that rascal and do some measuring

Not sure on an E-body, but I fit 24" cases under an early B; that car used 3" in and 2.5" out (tailpipes); tight fit on the tailpipes on that car around springs & frame rails & gas tank, which shouldn't be much of an issue on an E-body, I think.
When you're under there with the measuring tape, if you're planning on 3" tail pipes, remember that the 3" bend is gonna take up some room.

On my Duster the 14" tucked up where it was supposed to. The 20 and 25 were too big to fit in the kick up area under the car. I want to say there is somewhere around 16-18" of room under there.

"stock muffler location" on an E-body is behind the axle.

Not sure exactly how long they are, but I used to have a pair of 4.5" diameter inlet/outlet, center/center, Flowmaster 2 chamber top 10 series race mufflers mounted in front the axle on my '70 cuda. Those mufflers are real thick, but not much longer than a typical performance muffler.

Thanks for the replies


Cab...I'm on the road most of the time so I don't always have access to the car. I try and get parts ordered before for when I get back.

John...I thought there were mufflers in front of the axle and resonators next to the tank?

An8sec70cuda...beautiful car. My exhaust will be the same as yours but with the 3" pipe and turn downs in the same position. My car is a street car so I am trying to keep it quieter with the Ultra-flo's. While I have your attention...I would love to hear how you have the rearend setup. I am building a 9" for mine but would live to have a similar tire size etc.

Thankyou! If I were you, I'd set your 9" rear up w/ the '68-'70 B body dimensions and use the Dr. Diff offset spring hanger kit to use a 15x10 rim. His kit allows you to bolt in a B body rear and fit a 10" wheel pretty easy.

Mine is a stock width E body rear w/ stock front spring location, but I use the .850" offset rear shackles to get some added clearance and to make the springs closer to parallel. They're wider at the rear in the stock configuration.
I use 15x8.5" wheels w/ 5" of backspacing and run both 295-65 radials or 29.5x10.5 slicks on it.
Just trimmed the inside of the wheelwell lip to clear the tires.

Here's a pic w/ the slicks on it.

Other way around, the resonators (when installed) are in front.

Thanks for the info John.

An8sec70cuda...thanks for that information. I think I am going to have to do some measuring etc. The 9" is about an inch shorter then stock. I may have to fab up some offset spring hangars and hope for the best or use Dr. Diffs. I am still collecting pieces. Love the hood also on the car. I just put one on 4' though.