The case of the exploding muffler
 

This is an interesting one...

So, I'm helping a fellow rotarite (Juan) with his FD. He just put a motor in it and the car isn't running right, so I'm going through things getting it 100%.

The car has a downpipe, midpipe, and stock cat-back.

Fired it up, and it sounded like the end of the world, SUPER loud and lots of popping from the exhaust. Drove it around the neighborhood and was cringing at the neighbors looking.

So, to keep neighborhood peace, I pulled the cat-back off and replaced it with one of the exhausts in my collection. I figured the stock cat-back had some rusty holes in it or something.

The top of the exhaust is TOTALLY blown open, like from an explosion. See the pics attached. It's the damnedest thing I ever saw.

I'm not sure if it got a big backfire that blew it open, or some kids stuck M80's in it, or what.

Anyhow, had to share. That's a new one on me!

Dale

Dale,

Looks like someone on the West Coast just experienced the same thing...

https://www.rx7club.com/west-rx-7-forum-193/those-who-thought-i-joking-about-my-blown-exhaust-891453/

Charlie

Holy sh*T! That's crazy!!

I saw that sort of thing (exploded muffler) a few times back in the day due to huge backfires... Get some un-burned fuel in the exhaust system along with some free oxygen and you have a bomb (or a flame-thrower). And, of course you know, rotary engines are famous for that...:lol:

I'm with Dave...backfire. Probably way more likely when your not running a cat. Impressive though, even if the muffler was weakend a little with rust, that looked pretty powerful. I'm surprised your friend didn't remember exactly when it happened.

Yep, a big ass backfire that sure do that. Happened in my first car, a '74 Datsun 260Z. One big backfire and BOOM!! The muffler split open along the seam. It was pretty crazy.

Based on your title, I would get the hardy boys or scooby do to investigate. :-)

that's amazing. Lick the exhaust tips. I suspect you will taste banana.

Big backfire (as was stated above). It's happened to a few of the FB guys over the past couple of years.

yup pretty common on the 7's it seems as well as the 8's. my friend fragged the stock cat on his rx8 on a road trip luckly it was waranteed! have you priced a stock cat for an rx8 lol

z

Holy crap! Midpipe+ big backfire+ original catback = that? turbo rotaries continue to amaze.

Whats the mileage on the car?

i had the same thing happen to mine right after i bought the car