19MC70 Posted November 22, 2006 Share Posted November 22, 2006 I'm wondering if someone could help me out with part numbers for mufflers for a 70 model with factory duel exhaust. What is the inlet an exhaust tube sizes? My 36 yr old left muffler has a cracked inlet tube so I thought I start looking for a set. Thanks for the help. Chuck Link to comment Share on other sites More sharing options...
NateZ Posted November 22, 2006 Share Posted November 22, 2006 I'm wondering if someone could help me out with part numbers for mufflers for a 70 model with factory duel exhaust. What is the inlet an exhaust tube sizes? My 36 yr old left muffler has a cracked inlet tube so I thought I start looking for a set. Thanks for the help. Chuck Factory dual exhaust should have inlet and outlet sizes of 2-1/2". I looked up the factory part number for a '70 muffler and came up with 3973802. I also did a part search using that p/n but came up empty. Probably that part number has been superceded by another number somewhere along the years. Sorry I can't help you more. ~ Nate Link to comment Share on other sites More sharing options...
wallaby Posted November 23, 2006 Share Posted November 23, 2006 Hmmm...my '71SS had 2-1/2" inlet, with 2-1/4 outlet and the tailpipes were also 2-1/4 for everything aft of the mufflers. It's an old car so maybe the pipes had been changed in the past, but seems weird if someone decided to downsize the pipe size when replacing. Link to comment Share on other sites More sharing options...
NateZ Posted November 23, 2006 Share Posted November 23, 2006 Hmmm...my '71SS had 2-1/2" inlet, with 2-1/4 outlet and the tailpipes were also 2-1/4 for everything aft of the mufflers. It's an old car so maybe the pipes had been changed in the past, but seems weird if someone decided to downsize the pipe size when replacing. So your chrome exhaust tips aren't 2-1/2"? Link to comment Share on other sites More sharing options...
wallaby Posted November 23, 2006 Share Posted November 23, 2006 Well, I have to admit that the car was missing the tips. I've never tried to install new ones...are you saying that the tailpipes should be 2-1/2? I could imagine someone using a muffler with a 2-1/2 in & out, then hooking it to a 2-1/4 tailpipe, but I'n kinda surprised if the car had it's tailpipes changed sometime before I bought it (1978). I presently have 2-1/2 tailpipes on the car. Did I unwittingly upgrade to stock? Link to comment Share on other sites More sharing options...
NateZ Posted November 23, 2006 Share Posted November 23, 2006 Wallaby, I think you may have ... or I'm completely wrong. My Monte has 2-1/2" inlet and outlet, and the SS tips (used on both the Monte SS and Chevelle SS) have an inner diameter of 2-1/2", made to slide over a 2-1/2" pipe and be clamped on. Link to comment Share on other sites More sharing options...
19MC70 Posted November 24, 2006 Author Share Posted November 24, 2006 Thanks for the info! Now all I have to do is find me a set. Link to comment Share on other sites More sharing options...
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