Rear Muffler Delete
 

I have a couple questions about a proposed plan that i am about to try and do if i get some answers... I am thinking about taking out the rear axle back portion of my stock exhaust for some more sound until i get enough money to purchase a turbo xs cat back... I am planning on replacing the stock muffler with a 90 degree bent 2.5 in inner diameter pipe to go over the cut off portion before the muffler ( the bolts are completely rusted) And weld the 90 degree pipe so it turns down before the rear bumper. It wont be exactly 90 degrees because the pipe bends appr. 20 degrees upward towards the muffler. I am retaining my cat and resonator. But i do have a couple questions...

How loud will it be on a scale 1-10?
Will it affect mpg at all due to the back pressure of the rear muffler?

No bashing please.

just save your money so u can get the quality sound you want with the turbo xs

Have you ever heard a rotary before? DO NOT DO THIS. This is a VERY dumb idea with any vehicle and specifically a rotary egine. The resonator is not enough. If you really want to know, unbolt/cut off the rear bolts and remove the muffler for a few minutes. Have new bolts on hand, start car,feel stupid,reinstall muffler.

I replaced mine with a Flow Master 44 but was short on parts in the midel of th install and had to drive it to the parts store with no muffler and it was stupied loud a 10 on your scale I felt like a jack ass for the 5 mile trip I had to make

did you still have your cat intact?

This would be a 17 on your scale.

An uncorked rotary is unbearable.

Ya sounds like a racecar. It's def unberable. I turned mine on before reinstalling my muffler and it is stupid loud

It would not have a muffler, but still a cat. Does the cat not cut down on very much sound? Does anybody know what db it would be?

Prob like 120. Just don't do it

Ok thanks guys

yes I did

I removed my rear muffler. I just have a turn down after the rear differential. My cat is also gutted. Its loud, but doesn't sound bad.

Ok... So would an rx8 with a cat, without a muffler be as loud as my Si was with a dcrh and skunk2 70mm exhaust?

Who cares if its louder, its all about performance. When I first put a turn down on before I gutted the cut, the car was loud, but had a very aggressive tone. Now with the cat gutted, it just sounds pissed off.

your rotary will be louder than most engines uncorked.

Just disconnect the muffler as someone above stated and you will hear. I tried and it is not as loud as some are saying, but dont listen to us, just undo the muffler and move the pipe up out of the way. and you can hear. To me it seemed to perform better muffled, but then again it may have been the annoying sound that made it feel slower?

I would go with a 4 on idle, then a 8 on wide open. Then again I have more experience with 1st gen Rx-7's and they are much louder than the 8!

Ok... A friend of mine has a 2nd gen rx7 and i went drifting with him and his friends at Beaverun and if his straight through na is quieter than an 8 with a cat and turn down, then i think ill be fine. Thanks.

As someone who has actually driven a rotary to work and back (~35mins each way) with no exhaust, I think I can give some input. Granted, it was a turbo FC and the turbo does quiet it down a lot. It's actually not crazy bad if driven gently, but I would not recommend it. It was VERY loud if driven hard. I would imagine an RX-8 with a cat would be significantly more livable. I would imagine the side exhaust ports should take out a bunch of the nasty noise produced with a PP exhaust. Again, I doubt you want it that loud.

I don't think you're going to gain more than a few HP doing this. Do some research into how much HP can be gained with the mufflers. It's not worth it. The cat is where power can be gained. Why not put in a straight pipe where the cat is? You can save money on the catback and get a volume increase.

But the only downside to that is that i cannot pass inspection. I can although pass inspection with a turn down and hollowed cat... PA doesnt have a sniffer and only requires a "cat" but can be hollowed out... It just has to look like it works and you cant have a cel. Another required to pass the exhaust portion is to have some sort of sound supressor... ( factory resonator)

What about swapping the cat in midpipe out for the inspection?

then there is the whole "What if i get pulled over?" issue

you are going to get pulled over more not having any exhaust compared to having an exhaust with a midpipe...

If you drive this car daily, I wouldn't recommend doing this. I did this, but only because I drive the car as a track car only -- and to/from events. It's stupid loud. It's embarrassing loud. Below is a video of my setup -- no cat, no muffler, just a supertrapp. As posted in another forum, this also caused my bumper to melt.

Anyways - here is a quick video -- this does NOTHING to show you just how loud this is. When it's being revved up -- I'm only hitting 3k RPM's. If while on the street, I hit anything above 3k, everyone and their mom knows I'm coming. I did this for weight savings, not to sound/look pretty. But hey, on a track -- nothing sounds like an untapped rotary!!!

[EMBED]http://www.youtube.com/watch?v=b_DzK5YCi6k[/EMBED]

^
This guy is 100% right. If you decide to go with out a muffler it is a must that you get the end of the tail pipe from under the car or your shit will melt to much heat.

Here was my quick and easy solution if you have some welding skills and a high performance Flow Master 44, and it has to be the 44 the were built to flow big blocks in the quater mile therefor it is the only model Flow master that can handle the heat of an RX8 and the muffler is only 80 bucks plus the U bend my system cost me 100 bucks and has that sweet deep mellow Flow Master sound. Let the hating begin :rofl: