Hey,

Well inspection came around and the only thing i need is a new muffler (woohoo). So figuring sooner or later I want to go to a 3" catback I ordered a Ultra Flow from through advance auto parts (came to 80 and change part number 17227). Well this muffler has a 3" in and two 2 1/1" out (these look like ID from my quick check once I got the muffler). Now my problem is that my I pipe is 2 1/2" (same diameter as the outside of the outlets of the new muffler) and the outlets on the exhaust are approximately 2 1/4" (measuring the OD I got a number a little bigger through a 2 pi R math). Now I have to get the muffler on by the end of the week to get my inspection sticker without getting charged for another inspection and I don't have the money to replace with a whole catback. I want to use reducers but I have no idea what to use, I know summit has a 3" to 2 1/2" ID reducer, will this work? I have a feeling I'm going to order the parts and end up being a 1/16" short someplace (as in too large wont fit together). I've tried calling muffler shops I've only gotten a "thats an odd size call someone else". I see they make tailpipe expanders but they seem not to be made for making a 1/2" change in pipe. Am I going to end up paying a lot for the reducers, should just buy a 20 dollar econo muffler and focus on the catback for the future? This is my first time dealing with exhaust so Ive been spraying everything down with penetrating oil and letting it sit over night (hopefully itll make it easier....)

Also this is for a 1989 IROC 5.7L single cat setup.

Thanks a lot for any ideas in advance,
Martin

 

I think you will have a hard time finding off-the-shelf reducers to do what you want. As I understand it though, most exhaust shops should be able to custom expand a pipe to fit your needs. However, as far as cost, I'm guessing that you will end up with around $30 in reducers, making your muffler cost around $110. My Hooker catback cost me $207 from Jeg's, and others cost a little more, some may be less.
If it were my money, I'd do the cheap fix now and save my pennies. Hope this helps.

 

The reducer you need is a Walker pn 41974 for the inlet to the muffler. I would just get the 2-1/2" tailpipes from Walker, pn's 43243 & 43244. Walker stuff is available from any NAPA store or from Summit.