Proven Rear Cannons That Actually Work

[gtst25]

From what I've seen in real life and read there are a lot of people driving skylines suffering from drone syndrome. A total pain in the arse as it comes from bad design and not much thought.

Another thing I don't ever want to have is an exhaust that needs one of those push in restricters that people need to put in their rear muffler to make it bearable on the highway. You're effectivly restricting everything on the exhaust side so taking away performance and fuel economy gains.

I had a look at the HKS silent power system online but it shows no pictures of the mufflers seperate to the system - if you want a good flowing muffler I think you should be able to see straight through it ie no baffles etc. I'm interested if anyone here has fitted one of these systems and had a good look at all the components?

I've also found out the hard way that cheap mufflers that don't have stainless steel packing won't last a prolonged dyno session - 800 degree exhaust temps and next to no airflow will see your exhaust glow. That's what we think has happened with my centre muffler now - it seemed to get loud after the dyno tune but it was hard to say as I didn't drive it much before the tune.

Also I'm interested in twin pipes/twin resonators/twin cannons from the cat - a few gtrs run twin pipes right the way though but I haven't seen too many gtst's. Had a chat about it with my dad - twins must change the tune so to speak. A downside to this is the weight penalty.

Thanks for the input fellas - hope to hear more constructive comments.

Cheers

Edited December 18, 2006 by gtst25

[mokompri]

I disagree with you.

I didn't want to start talking physics, but sound is not a particle. I've included some basic information below about the nature of sound waves:

First, there is a medium which carries the disturbance from one location to another. Typically, this medium is air; though it could be any material such as water or steel. The medium is simply a series of interconnected and interacting particles. Second, there is an original source of the wave, some vibrating object capable of disturbing the first particle of the medium. The vibrating object which creates the disturbance could be the vocal chords of a person, the vibrating string and sound board of a guitar or violin, the vibrating tines of a tuning fork, or the vibrating diaphragm of a radio speaker. Third, the sound wave is transported from one location to another by means of the particle interaction. If the sound wave is moving through air, then as one air particle is displaced from its equilibrium position, it exerts a push or pull on its nearest neighbors, causing them to be displaced from their equilibrium position. This particle interaction continues throughout the entire medium, with each particle interacting and causing a disturbance of its nearest neighbors. Since a sound wave is a disturbance which is transported through a medium via the mechanism of particle interaction, a sound wave is characterized as a mechanical wave.

after all that, you have only explained how sound travels, not how power is lost.

power loss in the exhaust occurs when there is a restriction to flow. so, given a muffler with the same length of perforated internal tubing, one with an outside body diameter of 7" and one with 10", can you explain how backpressure is more in the 10" bodied muffler ?

EDIT: on the topic of things, anyone used the JunBL mufflers ? not japan JUN, the US company

Edited December 19, 2006 by mokompri

[Beer Baron]

i think JunBL is a korean company. 90% sure.

they do look ok though.

[mokompri]

this is the one im talking about, a well known exhaust shop in melbourne sells them

http://www.junblusa.com/

EDIT: any of you RB boys run fujitsubo ? the SR crowd seems to have praise for them

Edited December 19, 2006 by mokompri

[RNS-11Z]

JASMA stands for "japanese approved silenced muffler association, so yea it basically means that if the muffler/exhaust you have has that tag on it then it has passed a certain standard and noise level (i think the limit in japan now is 93 or 95db)

My HKS Silent High Power is jasma approved and is quoted by hks to be 93db, it is only a catback so when i finish the rest of the exhaust i expect it to get bit louder.But it does sound very good at the moment, a little bit drony sometimes but it is very toned, at 100kph you cant tell it apart from standard really

I have fitted the HKS Silent HI Power mufflet to my current exhaust. How ever i cut out the centre pipe. If you notice, from the inlet of the muffler, the size is 3in, 4 internal flow, how ever on the exit to the tip, its 2.5in with a pipe that runs half way through the muffler. I cut this out. Yes it made the car louder how ever, after changing from a cheap aussie made one, what a difference in noise. Cabin noise is lower, cruise noise is lower, WOT noise is louder though sounds alot better

h.

Note: i have no resonators or cat, straight throught exhaust with the just the rear.

h.

[gtst25]

http://www.nengun.com/exhaust/hks/high-power-exhaust-silent

This is the only cat back on nengun that's offered for the r33 gtst. I'm keen but don't know if the mufflers are straight through or have baffles in them - although I doubt they'd have baffles being an exhaust for turbo applications.

I see a few of you recommend the hks hi power silent - just would like to know if anyone here has personally purchased and fitted one of these systems? I need it to flow well enough for no restriction at 290rwkw and also it doesn't say whether it has one of those push in restricters which I really don't want.

Cheers

[seriesII]

just to add in while i found this topic. i have a full 5zigen exhaust system, front pipe, 3" split dump pipe, end tip would be 5" and cannon part 7", and this sound awesome, ive been trying to find this exhaust but came with the car when i imported, but i woud highly say 5zigen exhausts are nice sounding, i hear the rb nice purr, very smooth sounding, and from there, my turbo is louder then the exhaust sound. does any one know a site were all of the 5zigen exhausts are listed?, i would like to get the same system on my other car..

5zigen jasma exhaust

Edited December 26, 2006 by seriesII

[nizmo_freek]

http://www.nengun.com/exhaust/hks/high-power-exhaust-silent

This is the only cat back on nengun that's offered for the r33 gtst. I'm keen but don't know if the mufflers are straight through or have baffles in them - although I doubt they'd have baffles being an exhaust for turbo applications.

I see a few of you recommend the hks hi power silent - just would like to know if anyone here has personally purchased and fitted one of these systems? I need it to flow well enough for no restriction at 290rwkw and also it doesn't say whether it has one of those push in restricters which I really don't want.

Cheers

Hey mate

I have puchased and fitted a hks silent high power catback to my r33 gts25t, i seriously dont think it would become a restriction at 290rwkw and it is very very free flowing with a very large pipe size, some of the mesurements i took of the outer diameter of the pipes were, 3.5" for the 1st part of the catback which is from the end of the cat to the square flange which the 2nd part of the exhaust containing the muffler bolts to, and the 2nd part of the exhaust measured 102mm (if i can remember correctly) which im pretty sure is 4" which should be able to flow alot of air (lots of guys in the u.k use the silent high power on there gtr's etc, It also uses a bullet style center muffler instead of a oval shaped box muffler which will be less restrictive, and no it dosent have a push in restictor.

[nizmo_freek]

Heres some pics, i highly recomend the hks silent high power, i couldnt find anything that came close to it money wise (it is excellent quality, stainless steel so will last forever, great sound, JASMA approved so was rated at 95db, looks awsome, gave a nice increase in power) i am also now using a 3" decat pipe which has made it a little bit louder but not too loud (sounds awsome on song)

The only negatives about it is it does sit a little bit lower than a custom made system would but that really the only drawback.

[The Alchemist]

I have a HKS super drager on my GTR and its great, highly recommended. quiet as at cruise at 100km with ZERO drone.

Yet wind it up over 5000rpm and it howls like a banshee

[fishy]

nizmo_freek, that's a nice exhaust you have, how much do they cost btw.

i'm planing to change my exhaust as well since my exhaust hangs much lower then yours and drones more then a b^*tch.

i have a 3.5 inch pipping with a 5 inch tip or something(previous owner). i can even put my foot in it. =|

[nizmo_freek]

nizmo_freek, that's a nice exhaust you have, how much do they cost btw.

i'm planing to change my exhaust as well since my exhaust hangs much lower then yours and drones more then a b^*tch.

i have a 3.5 inch pipping with a 5 inch tip or something(previous owner). i can even put my foot in it. =|

Cheers mate

Cost me $1135 (New Zealand dollars) and worth every cent lol

[khunjeng]

I have a HKS super drager on my GTR and its great, highly recommended. quiet as at cruise at 100km with ZERO drone.

Yet wind it up over 5000rpm and it howls like a banshee

mine wasn't..,loud as an infact was EPA defect for it...but i did love it...

[khunjeng]

JASMA approved so was rated at 95db

In vic the limit is 90...regrdaless of being JASMA approved. not sure what is is in other states though.

[fEkuaR]

I have a trust turbo back exhaust, no muffler just the cannon on the back and of course a trust cat midway through. Other then geing rediculasly load on full load it sounds great. Doesnt sound drony to me but others might think otherwise.

[gtst25]

Cheers mate

Cost me $1135 (New Zealand dollars) and worth every cent lol

Thanks for posting up the pictures - I've been away from the computer for xmas so only just found your reply.

I'm thinking seriously about getting the high power silent - will post up how it sounds if I do.

Cheers

[kismetcapitan]

I've got an Apexi N1 4" catback mated up to a decat pipe and a Mines downpipe. I love the sound, but it's got the 3000rpm resonance something awful - in any gear, so long as the engine is pulling any sort of load. Had stock turbo elbows but those are getting replaced with Tomei units that will flow a bit better, I wonder how much they'll change the overall sonic character of the exhaust.

Oh, and JUN B.L is a Korean company. Not familiar with their products so can't vouch for them.

Edited January 1, 2007 by kismetcapitan

[nisskid]

ive got a 3.5inch straight through exhaust with a 4inch cannon on the back, it drones like a f**k but ive gotten used to it. if i could i would try and get rid of that drone, but i dont really see how without sacrafising performance.

might just have to buy soemthing expensive down the track.

Edited January 1, 2007 by nisskid

[khunjeng]

Also I'm interested in twin pipes/twin resonators/twin cannons from the cat - a few gtrs run twin pipes right the way though but I haven't seen too many gtst's. Had a chat about it with my dad - twins must change the tune so to speak. A downside to this is the weight penalty.

Cheers

You want twin cannons...here u go.

[adzR34]

You want twin cannons...here u go.

What do you guys think of Blitz nur spec R? in loudness and cruising drone?