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Discussion Starter · #1 ·
right now i have the stock exhaust piping with a cheap ebay muffler. i like the sound but it is falling apart. (from the inside out)

now i was wondering what would give me the similar sound but i wasthinking of going 2.5 cat back and i want to loose the ricer can, the clean/sleeper look is goal
 

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i got a magnaflow race muffler. it is a deep low tone and looks really good. rest of my exhaust was done by a muffler shop. 2.5in from turbo back
 

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do you have a 4 banger or a 6. if you have a 6 go with a 2.5 if you have a 4 go with a 2.25 you need enough back pressure for max power
 

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Discussion Starter · #5 ·
i have a 4 cylinder turboed.

im going to look around locally and see what the local shops have but im defiantly going 2.5
 

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Back pressure is the biggest load of crap I have ever heard of.

zoomzoom85 stop quoting misinformation if you don’t know any better.
Besides the fact that the engine in question is turbo charged and any unnecessary back pressure will only lower performance.

“Back pressure” as a term means pressure within the exhaust system.
Any pressure within the exhaust system makes it harder for the burnt charge to leave the combustion chamber.
Which in turn makes it harder for the unburnt inlet charge to enter the combustion chamber.

Sizing an exhaust system correctly results in lower pressure within the exhaust manifold.
To size an exhaust correctly involves taking many things into account not just the engine displacement.
Things such as bore/stroke ratio, desired useable rpm range, gearing, manifold primary and secondary length and diameter, etc, etc.
Or trial and error, changing sections of pipe until a good balance is found.

It really pishes me off when someone says “go with X size u need back pressure yo!”
The problem is that the size that they say is most probably close to right but not for the reasons that they think.
The reality is that with an N/A engine the smaller of 2 pipe sizes can often result in less pressure within the exhaust.
The reason for this is that for an exhaust to work efficiently the pulses should be tuned to assist in drawing out the burnt charge.
To do this there must be sufficient velocity at the collectors.

For example a bug spray atomiser is a big pump, it has a fine tip within which is a fine port to draw up the insecticide, now imagine if the pump had no fine tip.
Not a drop of insecticide will be drawn up.

The same goes for exhaust systems, chuck on too large a pipe size on an N/A motor and the exhaust velocity will be insufficient to assist in scavenging until higher in the rpm range.


Rants over, schools out.
 

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if you're looking for a non stock exhaust system, there are only a few options. im unaware of a borla system for the GD chassis, but that means little. the only mass produced one that i know of is the pace setter exhaust. however it is mild steel and wont last as long as the stainless steel systems. its also 1/3 the price. otherwise.. you're looking at a custom system being made
 

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Custom all the way. You will just need to decide on type and style of muffler. Personally I like the dual out look at 2.0" or 2.5". And lastly whether or not you wish to add a resonator (glass pack or magna flow, etc..)

Best bet is try to find a few sound clips of someone with the set up you are considering.

Good rant mx_masta, do you feel better... lol, good info though
 

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Discussion Starter · #9 ·
i have had the general concept of "back pressure" and needing to keep the velocity up on a n/a car to have any power.

i like the sound of the 350z muffler that kl-motor-sports got, but thats out of the questiong for me, lol.

but i was going to get a custom system at the local shop that my buddies go to, he gives some good deals.
 

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Back pressure is the biggest load of crap I have ever heard of.

zoomzoom85 stop quoting misinformation if you don’t know any better.
Besides the fact that the engine in question is turbo charged and any unnecessary back pressure will only lower performance.

“Back pressure” as a term means pressure within the exhaust system.
Any pressure within the exhaust system makes it harder for the burnt charge to leave the combustion chamber.
Which in turn makes it harder for the unburnt inlet charge to enter the combustion chamber.

Sizing an exhaust system correctly results in lower pressure within the exhaust manifold.
To size an exhaust correctly involves taking many things into account not just the engine displacement.
Things such as bore/stroke ratio, desired useable rpm range, gearing, manifold primary and secondary length and diameter, etc, etc.
Or trial and error, changing sections of pipe until a good balance is found.

It really pishes me off when someone says “go with X size u need back pressure yo!”
The problem is that the size that they say is most probably close to right but not for the reasons that they think.
The reality is that with an N/A engine the smaller of 2 pipe sizes can often result in less pressure within the exhaust.
The reason for this is that for an exhaust to work efficiently the pulses should be tuned to assist in drawing out the burnt charge.
To do this there must be sufficient velocity at the collectors.

For example a bug spray atomiser is a big pump, it has a fine tip within which is a fine port to draw up the insecticide, now imagine if the pump had no fine tip.
Not a drop of insecticide will be drawn up.

The same goes for exhaust systems, chuck on too large a pipe size on an N/A motor and the exhaust velocity will be insufficient to assist in scavenging until higher in the rpm range.


Rants over, schools out.

This.........:tup:

As far as a turbo engine is concerned, the best exhaust is none at all.
 

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Give vrs exhaust a call, I got a 3" turbo-back from them about 4 years ago: HOME

they are in Miami...look up tubing kits if you have someone who can weld it for you for cheap. If not, they offer complete turbo-back or cat-back systems.
 

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Discussion Starter · #12 ·
yea, i liked the sound of just open downpipe but mister police officer don't lol

spoolz - isn't the lay out for the exhaust different from the 626 and mx6 due to the extra doors?
 

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short stroker
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I believe there's a difference of only 1-2 inches in the wheellbase, but it would be worth calling them to verify.

I had them install mine in their shop and there was no issue with it, and I have an mx6. The cat-back portion is 2 parts, with a flared portion that has you slide the other piece in and clamp it. With my car is slides in all the way to the end of the flare.

It's possible with a longer 626 you wouldn't be able to slide it in all the way (it would still work though- the flared part is like 12" long), so they might have designed it this way just for that reason.
 

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Discussion Starter · #14 ·
yea, ill defiantlly give them a call and see, the only thing is that its like a 4 and half hour drive (ok, maybe 3 and a half :angel: ) and ill have to wait a little while to do that one i can't afford to take time off of work...:tdown:
 

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My car got down by a custom shop and he took out the resonator, sounds pretty good but girls and and family members can't stand it. Also the ICE really takes a hit.

Even a chain meineke or midas can do a decent job. Just talk with the guy out in garage bay and let them know what you want. And with local shops always bring cash! Its soo much cheaper
 

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Discussion Starter · #16 ·
yea, it looks like the resonator was cut off already so what i did was cut the piping off right in front of rear passenger wheel and made dump off for it. it actually sounds nice, its a little loud but i don't notice it.
 

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since you have the GT...go with straight pipe. I did...it's great
 
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