Jump to content
SAU Community

a nice sounding exhaust for n/a

rainster

By rainster,
in Engines & Forced Induction

 Share

Recommended Posts

rainster Explorer

rainster

Posted
Posted

hope this helps a few people out there in regards to nice sounding legal and powerful exhaust system .after alot of trial error with mufflers and resonator i have assembled a nice sounding exhaust it comprises of 2 1/4 pipe one 18'' expansion chamber coby muffler fitted where the cat was,as for u guys in oz fitt a shorter resonator 16'' expansion chamber type next in line with cat . run straight pipe 2 1/4 all the way up to the rear of car then either a large body straight through twin tip 2.5'' muffler or a 16'' straight through a 2.5'' core come out at 4'' with a provision for silencer use the silencer, give you enough backpressure to help with scavenge of exhaust gasses and prevents burnt exhaust valves still sound deep at idle and crisp sounding at mid to high revs also run coby extractors make a huge difference slightly in low rev and very noticable in mid to high revs. only adjustment had to do was idle air bleed scew adjustment to give smooth idle due to better flowing exhaust i have found it to have more torque and quicker acceleration .i havent dyno to show figures but works well for me and im very fussy when comes to making cars go well and sound well .also if u use a straight through type muffler comeing out 4 '' make sure u use silencer other wise it is extremely loud

Link to comment
https://www.sau.com.au/forums/topic/81513-a-nice-sounding-exhaust-for-na/
Share on other sites
Screamin' Skyline Rookie

Screamin' Skyline

Posted
Posted

All I got is the standard bore pipe (2" I think) headers and three coby's all about 15" long. The car has made 120rwkw on the dyno with this set up, how ever she only ran 108rwkw the other day :confused:

Anywho, I think the important thing is to avoid using stainless anything on the system as this resonates badly with the N/A's.

Also, a turn-down or dump pipe at the end will keep the bark away too.

I get many comments on how good it sounds :D yay!

rainster Explorer

rainster

Posted
  • Author
Posted
How about a 3" straight pipe? it will sound very mean. Probably be about 110 db.

i think 3'' a bit extreme.your dead right it would be very load it would sound like youre exhaust fell off.also you would loose a heap of power down low,only turbos modified could run that size and sound good,the turbo helps push the exhaust gas out,wear as n/a need a certain amount back pressure and smaller pipe size create scavenging to draw exhaust gas out and give good low down throttle responce .

Jago Mentor

Jago

Posted
Posted

can't have a quiet exhaust which gives good power. Plain and simple.

I'm gettin a 3" turbo back exhaust chucked on an ECCS RB20'd R31 GTS-x, won't be too bad :D

If you want lower pitched sounds then get mild steel, the thickness/density etc absorbs higher frequency sounds better.

dondesoto Community Regular

dondesoto

Posted
Posted

ive got 2 1/4 " pipes 1 x 18 " muffler and the cat converter and extractors . sounds deep at idle up to a great screaming noise at peak revs ,( yeah bit hard to describe exhaust sounds . its a bit loud overall , but tolerable

NA_R33 Grand Master

NA_R33

Posted
Posted

mine used to run a modified 2 1/2" collector off the coby extractors, straight through to a 2 1/2" 16" long cannon no cat... sounded unreal!! though any drive longer then 1/2 an hour resulted in headaches..

rainster Explorer

rainster

Posted
  • Author
Posted

i have being told by a few exhaust shops that you can have two identical models of car fit the same identical exhaust and they could sound totally different,i assume that vairables in engine build,machineing etc could be the cause of that.as for anyone that fits a 3'' system on a n/a car is wasteing alot of money,i no it looks good and at idle sounds good but the power loss at low to mid range is quite bad also take into consideration of fuel waste due to haveing to push down further on the accelerator to make up for power loss, trust me i have being there and tried that.best size pipe i believe is 2 1/2 for rb25 and for rb20 is 2 1/4 for low drone note at 50khm,i no some people like the car loud it draws attention but here in nz it draws the attention eg.police.these skylines are very hard cars to get a good sounding system and good power range without a bit loss in either of these factors its alot of trial error until you build up a system,even now im considering adding another resonator with expansion chamber i have noticed a bit of a loss power low down on hills

  • 14 years later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • MBS206
      ugently need expert / experienced opinion

      By MBS206 · Posted

      I wouldn't look too hard at what they did with the R32 GTR in endurance racing in Australia... Lots of things weren't actually available from the factory in the way those cars ran them... Japan also followed what Fred Gibson was doing here with some of there endurance cars in Japan... Australia is also the reason for things like the Brembo brakes, and the change in the gearbox... And quite a few other tricks they used to pull. There's a few other SAU peeps still on these forums that will have heard the stories direct from Alan Heaphy, Fred Gibson, and Jim Richards when we were lucky enough to have a great dinner with them
    • joshuaho96
      ugently need expert / experienced opinion

      By joshuaho96 · Posted

      For all the talk of "these parts are junk" I generally recommend OEM because it's really not as bad as claimed. I have never seen or heard of a case like the N63 where the oil returns completely clog with coked oil for example in ~10 years or less. Would it be nice if it were a straighter path? I guess, but most modern cars use a scavenge pump instead of a pure gravity return. Also the factory lines that would be relatively simple to convert to braided are generally speaking hardlines from the factory. I would consider braided line to be a regression, not an improvement. It's also been engineered such that all the hardlines have appropriate strain relief where needed. There's absolutely room for improvement, for example the HKS advantage heritage intake piping shows just how much can be done to make the turbos fight each other less in OEM twin turbo configuration and reduce compressor surge but it's rarely a simple/straightforward process. I recommend looking at what the group A/N1 cars did, generally speaking the changes they made were necessary and proven in endurance racing.
    • GTSBoy
      Turn signal wiring question

      By GTSBoy · Posted

      Yes, multi relays needed, and possibly a diode. I'm not actually going to think about it though.
    • VicFlo
      Speedo and odometer reading super slow r34gtt a/t

      By VicFlo · Posted

    • VicFlo
      Speedo and odometer reading super slow r34gtt a/t

      By VicFlo · Posted

      So I'm confident in saying its TCS thing. My new cluster I never realized didn't even have bulbs in the TCS or Slip slots. Shining a light through the backside that black plate has nothing for it, unlike my original cluster. Looking at the service manual the only thing that stands out is TCS in relation to the vehicle speed, it has nothing to do with turbos. It sadly looks like I may just need to get the appropriate cluster.
×
×
  • Create New...