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My mum has been busting my balls lately cause i told her about me just purchasing a hks super dragger exhuast with 2.5inch piping but its 2nd hand

she keeps nagging me to get her friend who owns a custom exhaust centre to make me one at pretty much nothing.....if i went with the custom made exhaust will i still get the increase in power made compared to a hks super dragger???? i dont think i would..so im better off with the hks yea???

bollocks. get the custom made one. if the guys making the exhaust have half a clue they should be able to craft one that gives you enough flow but still keeps the noise down.

i have no idea - i have heard that they are the shiz-nit

but others say not

i say go custom, cause the guys there have built it, and know whats in it, and if anything breaks or goes funny, they no what to fix.....

Isnt the HKS 3"? Cos then its too big..

Either way its better to go custom..

See if you can go balls out and get it made out of titanium!!!

If its possible.. I'd say screw HKS, get it custom, 2.5" titanium..

..yum yum..

haha cris

titanium = big big big bickies

the superdragger comes in 2.5, 3, 3.5 and i think even 4 inches daimeter...

Fully aware of this..

but..

she keeps nagging me to get her friend who owns a custom exhaust centre to make me one at pretty much nothing.....

:P

Even if it ends up costing the same price as a normal zorst.. or a little more.. your getting the same performance, saving ~20kg for a full zorst.. and the the *BLING* *BLING* factor

yea true how i know whats in it how it been built and guys will know how to fix if anything goes wrong

but only problem i have is finding a cannon muffler...i dont want a droaning xforce muffler i would love a apexi n1 to go on the end but yeah hard to come by with 2.5 inlet :P

if i can find a good muffler loud but not too droaning then ill go custom all the way.

actually cara it would be interesting to see a b4 and after dyno graph if you changed from the 3 inch to a 2.5 inch

one would imagine the mid range would beef up a bit and the top end would drop a fraction

3" is a bit big for an N/A i reckon... you won't get enough back pressure.... it'll kill your low end torque. comparing kw's before and after is pretty stupid when it comes to an exhaust, especially on an N/A. you need to focus more on the power delivery thru the rev range before and after. a good exhaust will boost your torque and power throughout the rev range, not just peak power.

one would imagine the mid range would beef up a bit and the top end would drop a fraction

not to mention low to mid would be ALOT more responsive.

Im with funkymonkey..

NA engines are about responce..

I laught when people say "I want 300KW"..

Focus your NA on responce and trorque with a beefy power band..

2.5" is good for an NA..

3" is a bit big for an N/A i reckon... you won't get enough back pressure volumetric vacuum/flow.... it'll kill your low end torque. comparing kw's before and after is pretty stupid when it comes to an exhaust, especially on an N/A. you need to focus more on the power delivery thru the rev range before and after. a good exhaust will boost your torque and power throughout the rev range, not just peak power.

exactly...

but for cara's purposes on the dyno, 3" is good i suppose.

my stance on custom vs. off the shelf (jap spec), will always lean towards the off the shelf item. NA RB's are notorious for their characteristic twin cam metalic ring, and it can be a headache to deal with if not done right.

i've never seen custom exhaust items as a positive, more as a negative - hks/fujitsubo, etc. don't invest big dollars into providing an item that has withstood the test of time as a bad product. things like tuned length, dB, emissions (fujitsubo legalis r?), flow, etc. are all factors that time has proven. i would very much prefer a proven product than one put together by the local guy who normally puts together 8 pots.

however if other factors such as cash is involved, then by all means prioritize your criteria accordingly.

back when I had an R32 GTS I had a fujitsubo legalis R exhaust and a legalis super Ex extractor system. was 2.5" and it droned like a bitch... plus the full stainless system added this tinny noise that made the car sound wierd when it revved.

ended up ditching the legalis R (sold it for a mint too to some brand name hugging buyer on ebay) and getting Tuffy's mufflers in sydney to make me up a custom exhaust. Again done in stainless steel, but this time with a proper resonator to get rid of that metallic noise from the exhaust, and cut down the drone. Still got a little metallic noise from the extractors, but it wasn't that bad. Since they were both 2.5" I didn't really see any change in performance or response, but the change in noise was amazing.

the problem with the fujitsubo, and I suspect with other japanese off the shelf items is that they are designed for turbo AND non turbo applications, not designed for use with an australian cat converter and don't have to meet the same noise emissions as we do. Getting a custom one made up will sort that all out for you.

the extractors and the exhaust:

m_superR.gif

m_superex.gif

i got a custom in mine, everyone said 2.25" and the exhaust guy so i got 2.25.. now everyones saying 2.5?

heres wat it sounds like with a magnaflow muffler and resonator :

http://youtube.com/watch?v=uRDVFAh0F24

hey leigh niceeee sound you have there

want someyhing similar bit more roary though but probably have the right sound with 2.5

ill have my mind made up once i speak to my mums friend the exhaust guy..

anyone heard of his company...called Pro X or something??

i got a custom in mine, everyone said 2.25" and the exhaust guy so i got 2.25.. now everyones saying 2.5?

Yeah people were telling me to get a 2.25" for any real benefits for N/A engines. 2.5" I guess is acceptable but probably would be better on cars with small turbos/ lower boost. 3" for bigger turbos and higher boost. I think anything larger than 2.5" on an N/A would = higher than 90db defect.

I could be wrong though.

i got a custom in mine, everyone said 2.25" and the exhaust guy so i got 2.25.. now everyones saying 2.5?
Yeah people were telling me to get a 2.25" for any real benefits for N/A engines. 2.5" I guess is acceptable

...

I think anything larger than 2.5" on an N/A would = higher than 90db defect.

I could be wrong though.

it's a compromise on an NA.

2.25 is what i would recommend for a car that's being driven around town, to the shops, to uni, work, etc.

however if you regularly see high rpm applications, i.e. track work - then 2.50" would be the ideal choice.

it's quite dependent on your application, none of this dyno rubbish in regards to kilowatts. everyone knows that a dyno reads maximum power at whatever rpm (more often than not, high rpm/near redline)

by choosing the correct exhaust diameter you are effectively putting your 'power/response/gigawatt/driveability' band in the range where you most frequently use it. there's no point in having a 11ty" exhaust, when you're only using 2000 - 4000 rpm daily,

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