"Custom" exhausts

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Apu
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"Custom" exhausts

Postby Apu » Thu May 12, 2011 11:42 pm

Quick question for those that have had an exhaust shop make them an exhaust system instead of buying on of the branded ones - I'm talking cat, mid pipe and rear box.

What's the upside of doing this instead of getting a branded system? I'm thinking it will be cheaper, perhaps a couple of kW less (but hey...a couple of hundred bucks for 2-3kW, I could live with that).

And...where did you get it done (in NSW) and the price range?

Many thanks!

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Re: "Custom" exhausts

Postby Gmi » Fri May 13, 2011 9:31 am

I had one done 2 years ago on my ep3r, changed the catalytic converter $450, the rest of the pipe in stainless steel 1600 all up at hitech paddington area.

Upside: none, unless you have a specific idea on how you want your exhaust to be.
Downside:
- you have no idea what it sounds like (mine was way too loud)
- crap resale value when you want to change exhausts
- Waiting time

I don't think it will be much cheaper now considering australias strong currency.
The exhaust itself is really high quality, and hitech does a lot of customs, so they know what they are doing if you really insist on custom.

I got a quote from them for my nc $780 for the muffler with twin tip. I would say it's more expensive now to custom than 2 years ago. I looked at greddy and fujitsubo entry level exhaust shipped to australia around 1k or under. So really depends on what you like, quality wise I would say around the same.

The above is all my personal opinion, some of my friends would only go custom. My choice would be to buy a second hand branded exhaust If there is any around. (ps: the power gains are so minimal if you have a stock engine, so don't expect too much, but it does feel faster with the sound :p)

Apu
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Re: "Custom" exhausts

Postby Apu » Fri May 13, 2011 11:21 am

Thanks Gmi! I've done the full route on my previous cars and as much as I convinced myself of "gains" at the time, they weren't sufficient to make a difference on their own (the power gained relative to weight).

I want better sound (a nice growl, not ear-bleeding loud), but at the same time, I hear of decent gains from exhaust systems for the MX5...and given the NB I have is "reasonably" light, I guess it's sufficient to "feel" a difference rather than just a dyno gain.

Would be interested to hear what others have experienced!

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Re: "Custom" exhausts

Postby rascal » Fri May 13, 2011 2:26 pm

My opinion is almost opposite to Gmi's

Upside:
- Price, usually much cheaper than buying a complete one piece system. At the time, I paid ~$500 for hiflo cat, 2 1/2 system with straight thru muffler and resonator.
- Can have it built exactly how you want, pipe size, shape, clearances, exit points, etc
- Can fine tune note if you don't like how it turns out. I tried two different mufflers and added a resonator before happy, all in same price. With a branded system in a box you are stuck with what you get.
- No waiting. Didn't have to wait for system to be shipped in, as shops hold piping, bare mufflers & resonators in stock. I drove into exhaust shop at 10am one Sat morning and drove out at 11:30 all done and dusted.

Downside:
- It doesn't come in a pretty box with brand names all over it

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Re: "Custom" exhausts

Postby Gmi » Fri May 13, 2011 3:59 pm

Was this in stainless steel?

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Re: "Custom" exhausts

Postby rascal » Fri May 13, 2011 4:15 pm

Gmi wrote:Was this in stainless steel?

No. Imho, stainless is a waste of money. I'll never keep the car > 10yrs to need the rust protection, and I've found they sound more tinny than a mild steel version.

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Re: "Custom" exhausts

Postby Gmi » Fri May 13, 2011 4:55 pm

rascal wrote:
Gmi wrote:Was this in stainless steel?

No. Imho, stainless is a waste of money. I'll never keep the car > 10yrs to need the rust protection, and I've found they sound more tinny than a mild steel version.


That is true. But you have compared the prices witha full stainless steel to a mild steel custom?! That being said a full stainless steel custom would not be much cheaper than the "branded" exhaust.
I don't know how much you know about cars or what kind of mods are in your car, but my personal opinion would be, how much better can you design an exhaust compared to hks engineers.

Anyways your car might sound really nice and perform the way you want it. I like how everyone have their own approach to modification, and it makes the whole scene more interesting.

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Re: "Custom" exhausts

Postby rascal » Fri May 13, 2011 6:17 pm

Gmi wrote:I don't know how much you know about cars or what kind of mods are in your car, but my personal opinion would be, how much better can you design an exhaust compared to hks engineers.

Enough to understand the difficulties facing aftermarket manufacturers.
As mine is for a track car, in my case I 'can' design a system better than an hks engineer, for the simple fact that I dont have to abide by the same rules and restrictions that they do.
Issues surrounding noise, vibration, resonance, fitment, intended market, etc, that they must compromise their design. materials, etc for, don't necessarily apply to mine. eg Low end torque is irrelevant to me, so I can run a bigger pipe than optimal for low end response, as it wont affect me at all..
I am able to get 'my' desired result with 1/1000 the effort/testing, and hence at significantly reduced cost.

Gmi wrote:Anyways your car might sound really nice and perform the way you want it. I like how everyone have their own approach to modification, and it makes the whole scene more interesting.

Exactly. each to their own..

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Re: "Custom" exhausts

Postby NitroDann » Fri May 13, 2011 8:05 pm

The name brand exhaust argument is as bad as people who think that the mx5 shouldnt be modified, who believe that no one is as good as the factory engineers. But the factory has to make a car that sells to the masses, are you a sheep who wants what everyone else does?

The hks team make an exhaust to suit a standard car, or do they? You dont know but your exhaust guy can make you anything you want for much cheaper.

If the factory always got it perfect you wouldnt want an aftermarket exhaust would you? :P :P

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Apu
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Re: "Custom" exhausts

Postby Apu » Fri May 13, 2011 9:39 pm

Loving the debate guys! Everyone is right in their own way! And I like the point about mild vs stainless. I don't intend on selling the car but I'll probably go for a mild steel unit anyway because it also allows me to change the system later without feeling like I've "over invested".

I want the exhaust for a "nicer" sound - I feel the sound I have now is like a sewing machine. More kW will be great but I'm not going to lose sleep over a branded exhaust producing 2kW more than an unbranded custom because in a streetcar, it'll make bugger all difference.

The issue becomes flow volume vs velocity, correct? So for a stock engine...2.25 or 2.5 inch?

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Re: "Custom" exhausts

Postby NitroDann » Fri May 13, 2011 11:21 pm

2 inch for a stock car.

Dann
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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Apu
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Re: "Custom" exhausts

Postby Apu » Sat May 14, 2011 6:47 pm

So I went to an exhaust shop and got quoted about $700+ for a cat and cat back system in mild steel.

Mania's full system is just under twice that in stainless (doesn't really matter to me) but it includes headers.

What I didn't realize is that the cat will have to be cut off on the NB8B...looks like the Mania system might be the better overall package. More saving to do...

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Re: "Custom" exhausts

Postby Mr Morlock » Sun May 15, 2011 8:16 pm

Vic seems well served with a cat back system from Town and Country Geelong and price is right. PCMx5 is the full bottle on this system- might be worth a trip at some point. Insofar as standard exhausts are concerned the OEM is a product built for a purpose and a price and the exhaust does its job for the majority of users. Most modern cars are very quiet and besides the occupants are often listening to their sound systems at mega volume or talking on their hands free and not notice what sound emanated under the rear bumper.

Apu
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Re: "Custom" exhausts

Postby Apu » Tue May 17, 2011 9:40 pm

OEM is another word for compromise...at least in my vocabulary! Anyway, booked in to MX5Mania for the install, so looking forward to it!

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Re: "Custom" exhausts

Postby Mr Morlock » Tue May 17, 2011 11:09 pm

I wonder what is the reasoning behind suggesting OEM is a compromise- who built designed and released the MX5. Many aftermarket suppliers are second raters whose QA systems and competence would not allow them to supply to car co's. I would have far more confidence in an OEM quality supplier / maker than a backyard outfit who has no idea of R&D etc.


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