Intentional Exhaust Leak

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Jimmynb
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Intentional Exhaust Leak

Postby Jimmynb » Wed May 04, 2016 10:18 am

Okay, So I prepared to be ripped into and called a ricer and whatever else you may wish to call me.

I have always found that I hate the annoyingly loud diff whirr of my nb8a. I always wanted an exhaust but I am unable to muster up the funds for a proper exhaust system or even a muffler ($350). So I instead created an exhaust leak intentionally. I removed my muffler and placed 2 spring washers on each bolt on the end of the muffler. Therefore when i put the muffler back on it did not seal entirely and i have an exhaust leak.

Yes I am aware that i may lose small amounts of power. Yes it does sound very farty and raspy. BUT for the cost of the spring washers ($3.90) I am pleased that I now have a louder car and can't hear my annoying diff whirr.

Further, when I am tired of it, I can reverse the process in under 5 minutes.

It reminds me of the cars that bought me into liking cars as much as I do. Those budget, zero f***s given, straight piped s13's and 180sx's that were so popular when i was younger.

I just thought i would share that for everyone to see.

Dont hate me for "ruining" your car by experimenting with my own path.

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Re: Intentional Exhaust Leak

Postby Trackphotos » Wed May 04, 2016 11:15 am

> Posts bad idea
> Acknowledges idea is bad
> Ends post with 'don't hate on my bad idea'
> Could have avoided any negative replies by not posting bad idea

Each to their own, go nuts. But why post if you both A), expect negatives replies, and B) don't want negative replies? lol.
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Re: Intentional Exhaust Leak

Postby Magpie » Wed May 04, 2016 11:31 am

Not the sort of thing a 'ricer' would do.

Refer to Trackphoto's post.

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hks_kansei
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Re: Intentional Exhaust Leak

Postby hks_kansei » Wed May 04, 2016 11:37 am

if it works and you're happy with it.

If you want an exhaust on the cheap you can buy a muffler for $20 or so at a wrecker and have an exhaust shop weld it in place of your current OEM muffler for $50
Or get a mate to weld it for free (you can use a $50 Arc welder to do it, wont be pretty but can be done)

Just grab the muffler off something with a much larger engine (or something turbo), since it's more likely to flow better than the OEM one, and sound a bit louder.


alternatively you can just remove the factory muffler and leave the exhaust to exit at the diff.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Jimmynb
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Re: Intentional Exhaust Leak

Postby Jimmynb » Wed May 04, 2016 12:39 pm

Trackphotos wrote:> Posts bad idea
> Acknowledges idea is bad
> Ends post with 'don't hate on my bad idea'
> Could have avoided any negative replies by not posting bad idea

Each to their own, go nuts. But why post if you both A), expect negatives replies, and B) don't want negative replies? lol.


I dont care about negative replies. I know it is a bad idea. But I am just posting to see what people say. I am not going to lose sleep or care if people say its ricey or farty. But if someone tells me that this will blow my engine up in 2 weeks i will probably listen to what they have to say ahahha.

Also there may be others who want to do what i have done but dont know how or what to do.

I am just posting to share my experience and desires.

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smy0003
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Re: Intentional Exhaust Leak

Postby smy0003 » Wed May 04, 2016 12:54 pm

Commodores do this kind of thing, but they mostly just punch holes in their mufflers with nails.
I guess what you've done is reversible.

If the reason was diff whir, did you try replacing the oil first?
It's good practice and can cost you less than $50.

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Re: Intentional Exhaust Leak

Postby hks_kansei » Wed May 04, 2016 1:03 pm

Jimmynb wrote:But if someone tells me that this will blow my engine up in 2 weeks i will probably listen to what they have to say ahahha.


Engine will be fine.

Only time you would be concerned with engine damage is if you run it with open ports (as in, no headers or anything)
Doing so can supposedly cause exhaust valves to bend/crack as when the engine is shut off the hot valves are cooled quickly by cold air.
With pipes on there is no cold air flow, so they can cool slowly.
No idea on truth in this, it's from the internet... but regardless, a muffler leak wont cause any issues.



as for the diff whine, as above, change the oil. It should be done every 80,000km off the top of my head.
If it still whines afterwards you've got bigger issues in there, so budget for a new diff at some stage.

For a cheap option if it whines after the new oil (and after a few days driving to make sure), buy a tube of oil additive to shut it up (Nulon make one I think)
It wont fix the problem, but it will mask it for a while.




I'd still be just welding in any old muffler though. I can't stand that pffffffft noise a leaky exhaust makes.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Re: Intentional Exhaust Leak

Postby SileNceR » Wed May 04, 2016 1:08 pm

Just weld a bit of pipe in place of your muffler

Image

Much less likely to melt your taillight and plenty loud enough (too loud if you ask me!!)
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Re: Intentional Exhaust Leak

Postby Jimmynb » Wed May 04, 2016 1:16 pm

I will change the diff oil this weekend then! Didnt know that could eliminate the noisy diff.

Also I am looking to buy a new diff soon, upgrading to a torsen or KAAZ or Cusco.

As for that straight pipe, I had the intention of doing so but i got a quote from an exhaust shop who wanted to charge some ridiculous price like $150. I cant justify spending that sort of money on such a silly mod. I just wanted to do something cheap and for a bit of fun.

Thanks guys

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Re: Intentional Exhaust Leak

Postby hks_kansei » Wed May 04, 2016 1:38 pm

Jimmynb wrote:I will change the diff oil this weekend then! Didnt know that could eliminate the noisy diff.


Well, sort of.
If the diff is a bit low it may help. But by the time the gears start to whine the damage has been done.
IF the issue is low diff oil (or really old stuff) it may fix it, or at least quiet it. And if you havent been driving with the diff whining for ages there may be minimal damage.

Think of it like this.
you have a stomach ache, you arent sure what it is but you're probably just hungry.
you eat something, and you might feel fine.
Or you might have been sick the whole time and still have a stomach ache regardless of food.




Jimmynb wrote:As for that straight pipe, I had the intention of doing so but i got a quote from an exhaust shop who wanted to charge some ridiculous price like $150. I cant justify spending that sort of money on such a silly mod. I just wanted to do something cheap and for a bit of fun.


$150 is too much for that.
I paid $50 to have a cat welded in mine, where they needed to add a section of pipe to make it line up.

Basically the same job as repalcing the muffler with a pipe, but in a tighter space.
Only difference is the extra bit of pipe, which you could frankly get from the bin outside any metal recyclers.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Jimmynb
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Re: Intentional Exhaust Leak

Postby Jimmynb » Wed May 04, 2016 2:08 pm

hks_kansei wrote:
Well, sort of.
If the diff is a bit low it may help. But by the time the gears start to whine the damage has been done.
IF the issue is low diff oil (or really old stuff) it may fix it, or at least quiet it. And if you havent been driving with the diff whining for ages there may be minimal damage.

Think of it like this.
you have a stomach ache, you arent sure what it is but you're probably just hungry.
you eat something, and you might feel fine.
Or you might have been sick the whole time and still have a stomach ache regardless of food.


Gotcha. I have had the car serviced many times and have never been told that the diff was out of the ordinary. I had heard complaints from other owners about the noisy diff whirr that makes it sound high pitch. However, I will change the oil this weekend as i am doing a fluids change this weekend.

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Re: Intentional Exhaust Leak

Postby SileNceR » Thu May 05, 2016 5:48 pm

for $150 you could just about buy your own welder and use some scrap from a bin outside an exhaust shop to make your own straight pipe!
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Re: Intentional Exhaust Leak

Postby hks_kansei » Thu May 05, 2016 6:04 pm

can pickup a secondhand Arc welder for under $50

Or a MIG for $150


Mig is wayyyyyy better for welding, but also costs more since you need to buy gas.

Arc makes ugly as hell welds, but it's cheap.



Apparently gasless MIG arent great, a mate had one and he basically said it's an auto feed Arc in the quality you get without the gas.
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Re: RE: Re: Intentional Exhaust Leak

Postby speed » Thu May 05, 2016 6:33 pm

hks_kansei wrote:
Apparently gasless MIG arent great, a mate had one and he basically said it's an auto feed Arc in the quality you get without the gas.


Yep. That's what mine was like without gas.
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Re: Intentional Exhaust Leak

Postby The American » Thu May 05, 2016 8:47 pm

I'm using a regular MIG with polarity reversed and flux core wire. It welds fine for home handyman purposes. You really don't need gas to use a MIG.


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