Okay so I have talked about this problem in a previous thread and have come for more advice / info.
There is bits of metal in my resonator which are driving me crazy, every time the car hits a bump or I touch the throttle it rattles. Previous owner said its bit of old catalytic converter in there.

So I have three options at this point:
A. Cut a hole in the resonator and try and get the crap out (could even be caused by rust inside resonator) and risk wasting my time on what could be a piece of trash
B. Ebay resonator for like £189.99 and risk it being crap quality, welds breaking, sounding terrible and potentially rusting apart in 2-3 years
C. Screw resonator all together and go to a muffler shop and have them weld me up a 3 inch Y pipe.

As much as I wish I could, I simply can't afford to buy a racing beat or whatever flow exhaust system. Far too expensive considering I'm paying for an RX8 which means half my wallet goes into the petrol station and the other half on the £555/year tax.
I'm leaning on the Y pipe simply because I've heard how they sound on Youtube, and especially with a high flow catalytic convert its phenomenal (id probably just keep the stock cat although I might get a catless mid pipe to use in-between MOT's when I recover some money). Yes I know its going to be very loud, I like loud cars. I can hear what the engine is doing better. I've had a straight pipe car before and loved it.

Has anyone had experience having Y pipes made? How much did it cost you? It has to be cheaper than a racing beat pipe or whatever but will it be more than the cheap ebay catback?

Thanks

 

What exactly are you trying to accomplish with the “y pipe”? You mean straight pipe, dual outlets? Straight piped Rotary is loud as hell. You do not want that.

 

Yes a Y pipe, or duel outlet straight pipe. I do indeed want it. I like my cars loud and fast. And i've seen many videos of it sounding great. Also heard one out in the wild in my area, sounds great. Its really not overly loud. It would be no louder than the many motorbikes which plague my area, those things hurt my years when they pass. Wow they are loud. The straight pipe RX8 i've heard is nowhere near as loud as those. And if its too loud... not a big issue since i'm replacing the midpipe at some point too. I can just get a resonated midpipe to tame the sound a little.

 

straight pipe 8 will make your ears bleed.

 

I'm any case, i'm not asking for peoples opinions and criticisms of my decisions. I just want to know if anyone knows the price range i'm looking at? Ball park figure?

 

call some muffler shops in your area. seriously just buy an exhaust, you can get a header back on the cheap side ~$500. no idea what a shop will charge for custom work. an aftermarket exhaust will sound better too. a buddy of mine ran a ebay exhaust for a while, sounded like ****. i had the agency power header back and its loud af but was about 500 as is the turbo xs system

 

btw thats not my opinion, its a fact

 

If it were $500, hell i'd buy a quality headerback right now. But no way am I getting a header back exhaust for that low of a price. Just a midpipe and catback from racing beat or another company is well over a grand. $500 is the range for a midpipe and catback from ebay. I live in the UK, If you can find a quality header back system for $500 i'll buy it right now. Its either **** quality ebay exhaust which is probably more annoying than my current rattling exhaust, or a loud *** straight pipe. Because there is no way in hell i'm spending over a grand on an exhaust system. I'd rather save that kind of money for an engine rebuild one day.

 

How much do you think custom exhaust work costs? There are no off the shelf Y Pipes for the rx8, so you need a hand built mid pipe and cat back. Guarantee it will cost a grand.

 

A grand? They'd be recycling my current resonator. All they'd have to do is chop off the pipe going from the flange into the resonator. Then chop off the two pipes coming out the resonator. Then just make a split pipe which just attaches the 3 parts together. I didn't realize exhaust work costs so much. I already have a welder and a grinder.... might as well get some scrap metal and learn how to weld myself. That a ******* ripoff for bending, welding and cutting some pipe.

 

most of us are in murica and have no clue what **** costs across the pond which is why i said to call local exhaust shops. pipe benders, welders and labor aint cheap neither is custom work. the rx8 is not a cheap car to modify and sucks on gas. doesnt sound like its a good fit for you if ya cant afford an exhaust system. im guessing you are young being that you are broke and want a straight piped rotary. good luck with it and post some video of ear drum destroying set up

 

Nah the car is a perfect fit for me, I can manage to fuel it comfortably. Its a solid and a lot of fun. I have some money saved in case I need to have the engine rebuilt one day. It costs £900 for a basic rebuild here so $1200.
I'm really just looking for a cheap solution to my resonator problem. The metal shards or whatever inside it shaking around is driving me crazy. People actually turn and look at the car wondering whats wrong with it.
I assumed that a straight pipe would be the cheapest option. Or at least a better option than an ebay catback which would probably fail after a few years. It might be a case of saving up and getting something better. Nearly a grand just seems really steep for an exhaust considering I can get the engine rebuilt for the same.... and its just some metal tubing after all. I'd like my car to be a fair bit louder as the stock exhaust is actually really quiet. I'm just struggling to find the right option here.

 

Man, you know it might be a good idea to take your exhaust down and see what's rattling around in there. People have had their catalytic converters fall apart and have that rattle around inside. It's really not good, could create an obstruction and hurt your engine.

A 900 quid rebuild is a waste of time and money. That's just the seals and the work required to replace them, it doesn't address any worn out parts.

 

Yeah I probably wouldn't chose the £900 rebuild anyway (thats without vat and fitting). If they have the engine apart already and can do other stuff for a few hundred more. Might as well get it done properly.
I don't need to take the exhaust down, I know exactly where is coming from. The previous owner said he had the catalytic converter cleaned by the Mazda dealership and ever since some bits of catalytic converter have broken off and gone into the muffler. Thats all it is. Unless the inside of the muffler is also rusted out.
Its just incredibly annoying...... INCREDIBLY.
But I've been doing some research and it seems like I can have a completely custom exhaust made by some muffler shops around here for 300-400 quid. Thats a lot more reasonable to me.

 

Sooooo your catalytic converter has fallen apart? That's a pretty big problem. Bad cats kill engines. You cant clean a cat, that's not possible.

You guys have emissions testing over there, you can't not have a cat right?

 

clean the cat out with a big *** pry bar lol.

 

Hahaha I totally wish I could. I did on my MX-5 when I had it because it was import and before 95 so it was on the decat test. But emissions are so strict on MOT tests, i'd never get an RX8 past with no cat haha.

 

I mean, you can put the car up, take the cat/mid-pipe off, run it and decide if Y-pipe is a good idea.

Volume-wise, my roommate has a 91 Volvo 940 Turbo w/o muffler or resonator(he bought it like that), and the thing sounds like a tractor in the city. If anything, it wasn't "cool", just really hilarious. Rotary is probably even louder than that, so yeah, you will attract the fuzz pretty easily.

Also, the frequency of rotary is higher than piston engines. Even if the volume doesn't get you, the frequency will definitely make your ear bleed.

As for the rebuild kits, I don't see housings included in any of them. Housings are probably 500 quid each, and you will probably need the side plates as well(or at least get them refinished). In the US, even a reman engine from Mazda will cost about $3k w/ $1k core, so a quality rebuild will be at least that.

You can probably get a used good cat for emission tests. Usually, people just have the OEM cat for emission tests and take it off when they are done.

 

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Yep, that's what I plan to do. Switch the cat out just for emissions. I want to go catless. But obviously my priority is doing something about the rattling muffler now.

Might just take the exhaust off as you say to test it. But whether I hear the guy in my area with his straight pipe 8, it sound awesome.
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To borrow a phrase, "A straight-piped rotary sounds like taking a chainsaw to a tin shed... from inside the shed."


You are contemplating a straight pipe and are worried about how the audio system sounds in another thread? Does not compute. A straight pipe drones like crazy at all the wrong frequencies and will make your brain bleed after just a few minutes. It's terrible inside the cockpit. Absolutely terrible.



Pull your exhaust, inspect it, and clean it out. If there is anything wrong with your cat, it can kill your engine in short order (as in a few days sometimes), so you need to do it anyway.

 

Well I dont want a drone. I just want to make a bit of noise when I hit the gas hard. The cat was recently cleaned by the mazda dealership, so its fine. Just a couple of bits have fallen into the resonator. The exhaust is far too quiet right now.

 

A cat cannot be cleaned. Whatever the previous owner thinks they did, they did not do that. If pieces have separated from it, be very VERY certain that it is NOT fine. If they gutted it, you won't pass emissions, if they didn't gut it, and it has crumbled it's slowly killing your engine by blocking exhaust flow. Fix your car man.

 

It passed its last emissions test only a month ago. So it can't be that bad. But it certainly has crumbled a bit. If its really likely to hurt my engine i'll shift my priority from the rattling resonator to a decat mid-pipe. I should be getting paid next week so i'll be able to buy the mid-pipe and some tweeters to improve my sound :D I'll just put the cat back on for MOT.

 

There's the possibility that the exhaust hanger flange is hitting the frame, which also causes rattling as well.

Hard to say without you actually looking at the car. It's all just speculation and guesswork now.

While I don't have a straight pipe, droning on some stock piston cars is enough to drive me nuts. I have driven a rental 17 Suzuki Jimny and 99 Toyota Corolla, both stock with 5-speed. If you go fast enough on highways with both of them to get to 3k RPM, they get quite noisy and you need to really crank up the radio to combat it. Now imagine a rotary without any resonator with a sharper tone.

 

Not its not a vibrating noise like the hanger would make. There is free moving bits of metal inside the resonator. I can hear it when I kick the resonator. And they slide around when going around corners