AMC Eagle Den Forum

The Mighty 258 => Exhaust System. => Topic started by: flamingchariots on March 03, 2013, 11:01:49 PM

Title: Tailpipe size difference?
Post by: flamingchariots on March 03, 2013, 11:01:49 PM
This is for an 84 wagon 6 cyl.
I'm changing out the muffler (AP brand #6552) that went bad after 3 1/2 years.  I think that I still have the original tailpipe on the car.  It is 1 7/8".   I'm using a Walker replacement that I bought several years ago (#44537).  I see that it is 2".

Questions:
1) Will the larger size affect back pressure in a negative way?  I don't want to create problems.

2)  The new tailpipe is the same size as the muffler outlet.  I bought a 2"x2" adapter sleeve that fits over both; is this OK, or should I buy a sleeve that fits inside of both?  I'm thinking if it fit inside, it would be more like the original diameter and it would be easier to air chisel (the muffler) off when I eventually have to.  I also may have to cut some off the inlet end to make up for the butt joint.

3)  The new 2" tailpipe is several inches shorter at the outlet.  I'm thinking a tailpipe extension tip would help?


Kevin
Medina, OH
Title: Re: Tailpipe size difference?
Post by: carnuck on March 04, 2013, 01:33:04 AM
Not really negative, but it may change the exhaust note. Many of us are running the 2" pipes to increase HP a bit for highway cruising. Once I get the EFI in my car (which will only happen if I sell one or more of my Jeeps right now so I have $$ to do it) I'll have 2" front to back
Title: Re: Tailpipe size difference?
Post by: BenM on March 04, 2013, 11:43:15 AM
I think you're over-thinking it.

The tone will be a little different, a smaller muffler is usually louder, and just using the outside fittings should be sufficient. You should also be able to find a piece of make-up pipe at an auto parts store and just trim it to fit. I've cobbled pieces in occasionally.

Scientifically, the pipes are a turbulent flow anyway, and the little bit of lip on the pipe isn't going to make an appreciable difference in either direction.
Title: Re: Tailpipe size difference?
Post by: flamingchariots on March 04, 2013, 02:38:48 PM
Well, I had the dimensions slightly wrong.
The standard muffler (which I have) has a 2" pipe inlet and a 1 7/8" outlet.
When I figured the sleeve, I butted it up to the wrong end!  So a 2"x2" will not work.
The correct fitting for this is a 2" ID x 1 1/2" ID reducer,  part # 548506.
This may help someone searching in the future.

Thanks for the comments.