Exhaust for 1.6L NA

[mitch_f1]

SO I am looking at getting an exhaust made up for mine. Just bought a set of extractors on eBay with a 2" outlet. I am also looking at getting a high flow cat (which one??). But as for the rest of the exhaust, what should I do? I had one shop saying "i would run a 2.25 inch mandrel exhaust with resonator and a step down muffler on the rear 2 inch (speeds up gas flow as gas temp cool down) all in mild steel....and dress it up with a stainless tip." The cost of which would be $500

Basically what I want out of it is just a bit of noise. Did my first track day yesterday, and one of my problems was not being able to hear the car!!! It really pissed me off. So I want to be able to hear it, so it has to be fairly loud, but I also want a bit of performance in the low to mid range. Not worried at all about looks or nothing.

Which cat do i get, should I get one with a 2.5" inlet/outlet or stick with a 2", which density 100cspi or 200 or something else? Which brand? Magnaflow? Xforce? Something else?

Has anyone got a really good setup for road/race that is loud, but not busting your ears around town loud?

Also, is there any benefit to removing the muffler on a NA car?

What are the stock exhaust dimensions for a 1.6L as in pipe width?

Ebay extractors:

[mitch_f1]

anyone??

[93_Clubman]

mitch, may be have a read of a few recent exhaust threads:
viewtopic.php?f=29&t=40743
viewtopic.php?f=29&t=32126
viewtopic.php?f=29&t=25680

[mitch_f1]

I have, I even read some from a couple of years ago, but none answer my questions

[93_Clubman]

Kept my old NA6 standard, so can only speak from experience of my NA8, which I've put a full (extractors to tail pipe) Stewart/ CES system on. Assuming you're still in Sydney, have you asked MX5 Mania what they suggest & stock for an NA6?
These might help: viewtopic.php?f=29&t=33693
search.php?keywords=na6+exhaust&terms=all&author=&fid%5B%5D=29&sc=1&sf=all&sk=t&sd=d&sr=topics&st=0&ch=0&t=0&submit=Search

[mitch_f1]

So I have just then read pretty much every single topic pertaining to exhaust on an NA NA6, and I still have questions that need answering:

-Is there much of a difference in power/response in removing the cat or the muffler or both on an NA car

-Which cat is the best to go for, I have been told not to go lower than 200cspi??

-has any one used/heard of Berkley/Berkeley mufflers???? Sound clips?

-would there be much of a difference between NPower and Magnaflow mufflers in terms of sound/performance??

-What are the stock pipe sizes on an NA6...like everyone has been saying 2.25" is the way to go, but is that much bigger than stock??

[sweep77]

for a standard na6 im sure any quality sports muffler will be fine. most people run 2.25" pipe to a resonator and back to a sports muffler. 2.25" seems to be the best size in terms of performance and noise. I had a highflow cat, mild steel 2.25" system with resonator and stainless muffler and sounded great and went really well. was loud enough but not annoyingly so. you really only need extractors if you want more topend but on a na6 you wont notice much difference

[StanTheMan]

no cat will be soo noisy you'll get a defect in no time.
its also illegal something like a $10000 fine if get caught.

as far as extra performance goes leaving the cat off altogether is only going to make 2-3 rwkw. at best. which will not even register on your backside. The only difference is if you want a Dyno queen.
so don't leave it off IMHO.

2.25" is a fair chunk wider than stock. There is also a reason why they recomend 2.25" for an exhaust. Just because something is bigger doesn't mean its neccecarly more effeicient. I'm sure its something to do with back pressure & getting a certain air flow going where it kind of has more momentum as it starts flowing & therefore acually get the air through quicker than say a 2.5" system. For tubo aplication The 2.5" is a better option.

if you want better throtle response remove your AFM, widen the air intake, install some cams & ECU.....as well as a lighter spring on the accelaerator pedal. maybe even lighten the flywheel.

[93_Clubman]

Standard NA exhaust was 1 7/8", & deleting cat as STM & previously Oki (elsewhere) have said will only provide a very small gain power & be illegal.

[goonie]

If I were to get a 2" exhaust system on my NA6 (roadster if it makes any difference), should I bother changing the piping and muffler from cat back if it is already 1 7/8 inches?

So it will be new extractors and a high-flow cat with the standard system from cat back. Will the 1/8 difference in piping make a big difference? Is the standard muffler restrictive?

In an attempt to answer my own question, I'm guessing it's all about flow, so would the standard system be restrictive in some areas (eg, not mandrel bent)?