Exhaust for na NA

[deez]

I'm after more low-mid range power and torque and am tossing up between:

1. CAI, cat-back exhaust and muffler
2. CAI, full length exhuast and muffler with hi-flow cat

Would there be a considerable performance difference between the two options? Is it worthwhile shelling out that extra $$$ for option 2?

What is a good diameter exhaust/muffler for enhancing performance?

Would either option not be worthwhile without headers?

[green_comet]

I have hpc coated headers, hi-flow cat, 2 1/4 inch pipe, resinator , and stainless hi flow muffler at the back. Made quite a bit difference in power, its alot more fun to drive now. The mania cold air intake made a difference too, gave it a little more higher in the rev range..

But dont expect a huge difference, like you would going turbo or something..

I cant wait to get myself a supercharger.... **drool**

Get the whole lot done, headers, cat, exhaust, and cai..that way you know its all done, and you wont have to go back to add anything later on..

[deez]

Get the whole lot done, headers, cat, exhaust, and cai..that way you know its all done, and you wont have to go back to add anything later on..

I'm on a shoestring budget But that does sound good. How much did that all cost green_comet? And was the exhaust you put in a full length one?

What's HPC coated?

Thanks

[Fatty]

definately do the cai. d.i.y job shouldn't cost much at all.

also you can pick up some good cheap power with a dfa by leaning the fueling out a bit across the board. i found my car went a bit harder in the midrange once i had the dfa tuned nicely.

[Fatty]

mikey, i have the mx5 factory cai on my car. it is a great set up. see my picture in the other thread about home made cai.

as much as i like it, i think a diy job is probly 80 - 90% as good, for a lot less money.

don't know anything about the exhaust they do tho, sorry.

[deez]

definately do the cai. d.i.y job shouldn't cost much at all.

also you can pick up some good cheap power with a dfa by leaning the fueling out a bit across the board. i found my car went a bit harder in the midrange once i had the dfa tuned nicely.

Sorry what's a dfa?
haha pardon my ignorance

[Boags]

Digital Fuel Adjustor. From Jaycar, about $150 if you can build it yourself, and then you have fuel control.

[JSE]

its hard to improve on the standard headers/extractors. the way they were designed 4-1 is good so if you add headers/extractors you will get very little gain in performance. I choose to keep the standard headers and I put a hi-flow cat and 2.25inch exhaust with muffler on mine. All was custom with a choice of exit tip for just $500 installed. Was quoted $260 installed without the hi-flow cat. Better throttle response and gains a bit more legs above 4k rpm - love the sound of the little 1.6 with it but

[green_comet]

Deez read the link, it will tell you all you need to know about HPC coating.

http://www.hpcoatings.com.au/pages/about.htm

Mine was a little bit more expensive, due to them having to install the extractors, and puttin a stainless muffler at the back.

$650 everything done, headers in, hi-flow cat, 2 1/4 inch piping, and stainless muffler..

Im thinking I might have to get one of those dfa's, and see how its all runs..

[Boags]

Im thinking I might have to get one of those dfa's, and see how its all runs..

I think there'll be one for sale pretty soon... Already built, just plug it in!

[rodent]

its hard to improve on the standard headers/extractors. the way they were designed 4-1 is good so if you add headers/extractors you will get very little gain in performance. I choose to keep the standard headers and I put a hi-flow cat and 2.25inch exhaust with muffler on mine. All was custom with a choice of exit tip for just $500 installed. Was quoted $260 installed without the hi-flow cat. Better throttle response and gains a bit more legs above 4k rpm - love the sound of the little 1.6 with it but

...and yet my old NA6 with completely stock zorst still kept up with it at the line!

[deez]

Thanks for all your input guys! Those prices are awesome comparison price points and I'll be sure to take them to Mania to see what they can do

[sirbob]

Like all things, you ultimately get what you pay for (Hey, its the laws of physics man...)

My NB had a 4-2-1 HPC extractors, 2.25' mandrel bent exhaust with hi flow metal substrate cat and muffler with 4' stainless tip. (all for $1600 fitted by CES racing systems in Brisbane) The performance gains were significant, but subtle. The main advantage in doing extracors is the increase in mid range torque, where the cat, and cat back will generally free up the whole rev range. Combining one with the other it the best of both worlds!

If anybody has had a close look at the standard extractors you will see how tight the corners are and how small the tubes are, which is clearly not going to flow as effectively as a larger diameter, larger radius pipe like most aftermarket extractors. Again, there are compromises here, as it is well documented that smaller pipes generally allow for higher exhaust velocities and increase scavenging which increases fuel efficency and low end torque, but starts to restrict gases at higher RPM.

It really comes down to what you want.

Me? well, i wanted the best system i could afford, with a good strong mid range, with good torque and a nice note. Thats exactly what i got, and it sounded hot to boot!

A CAI intake, similar to the mania style adds more torque again, plus induction noise, plus you get a good ram effect as the faster you travel, the more air that is forced into the intake and the more torque you get... Tis strange,contrary to my expectaions, my car used to accelerate to 100, then accelerate faster up to 140 as more air was fed into the intake.


My opinion:

DIY intake, but make it similar to mania, $300 is a bit rich for what is really a tube with a pod filter (albeit carbon)

The best exhaust you can afford, and do it all at once, that way it will always be good and you will not have to worry about adding bits in at a later stage. (Also, a complete exhaust should hold its value relatively well and hence be relatively easy to sell on down the track)

$2000 means they have seen you coming! Remember, my exhaust was basicaly a race-capable system for $1600 fitted, plus $300 for intake = $1900... You should expect to pay around $1500 to do what you want!