exshaust questions

[pandrade]

hey every one im gussing this is one of the first thing people do to there supra and thats an exshaust. currently my whole exhaust is 3in from including test pipe and the whole system. i have no cats or mufflers except a small megan raceing canister at the end whith goes from 3in to 4in( doesent look to ricey).

my problem is that i love the performence i have gained but there is quite a bit of drone noise especialy at cruze speeds( for me usualy 2,500) if at idle or above cruze it sounds wounderfull. i was thinking of glass packing the main section to help whith noise( great option for me since its about 20$ at my advanced) my thought is i dont want to lose performance i have now for a little noise cancelation, and this graph shows how much i would lose from my current 3in to a glass pack 3 in http://www.cherrybomb.com/Uploads/images/flowrates.jpg

and also i want it quieter and i am thinking of buying the vortex since it offers the best performance and muffles the noise quite a bit compared to the glass pack
http://www.cherrybomb.com/Uploads/images/soundchart.jpg

any thoughts?

[cre]

Personally a high end resonator and a high quality, straight through muffler have always been my preference. At a glance they're both straight pipe, not a single vane in the way of the exhaust flow but no drone, nice tone and an acceptible volume.

But hey, if they're just $20 I see no reason not to try it out. If you hate it or need something more you're only out the cost of the muffler and whatever you pay to get it welded in.

I've found that a muffler by itself doesn't always kill the 3 liter drone though. If the muffler doesn't help look into a GOOD resonator.

[pandrade]

like you said i was gona use the glass pack as a resignator but after looking at the flow and noise charts i would get better flow and noise cancilation from the vortex, yah its a bit pricer but id be willing to give it a try. you know of any good flowing and muffeling resignators?

do you think a diffret tip might help as well
this is what i have on( mine is a older one that did not come whith the silincer)
http://www.meganracing.com/product_d...d=388&catid=21

[cre]

A resonator is not necessarily a muffler and a muffler is not necessarily a resonator. The simple way to think of it is that a resonator is there to remove specific tones, turbulence or harmonics... That doesn't mean that it actually makes the exhaust any quieter, just smoother. A muffler is employed specifically to reduce volume. These may not reduce drone at all and, depending on the design, often add turbulencs and raduce the flow of an exhaust. Sure, you often see both terms used interchangeably, but if you keep them seperate you're more likely to design a system which you find pleasant.

My personal preference for resonators are Aero Exhaust's AR series. You'd want the AR30 for a 3" exhaust. My preference in mufflers is Borla, anything which uses a straight through design with a SOLID dampening material (ie: spun stainless steel and not fiberglass which degrades quickly).

For the sake of cost effectiveness I suggest you try just adding one component first and then decide is you need the second. I'd start with the resonator if the drone is really bad (which it usually is if your exhaust is bigger than 2.5").

[pandrade]

from my understanding i always belived a resignator was usualy behind the secondary cat and looked kinda identical( the resignator would give better tone and muffler lower volume, thats what i had belived) and a muffler looked like the heavy box or oval desighn

and thanks for the advice ill probably buy it on ebay since thats the oly place i have found it soo far, hopefully that solves some droneyness if not the borla muffler you suggested.

my drone aint bad at all in eather high or low rpm only at cruze like in 2400-3000 every where else sounds good. quick questin whith this resignator on will it considerbly afect the performance? im looking to keep the little performance i have yet still be able to take the girls out whith them going deaf

[cre]

It's resonator (as in resonate or resonant frequency) not resignator.

No, a well thought out setup may have absolutely no negative effect on performance.... Actually, in some cases it may improve. Much like a resonator helps the intake charge it may be employed to facilitate a more efficient exhaust flow.

Yes, the drone you're experiencing is perfectly normal for this size of engine and quite common.

[pandrade]

ohhh ok here i have been spelling the wrong thing the whole time lol.i knew there would be some droneyness from the begining but small price to pay and hopefully your advice will make a huge improvment on the drone issue, thanks again

[cre]

Exhaust and intake systems are like a wind or brass instrument. They can be tuned for a specific tone but remember that it's an instrument which is only capable of one note and that outside of that range it's always going to shift. Really there is a LOT to the design of exhaust and intake systems, much of which is way beyond me, and so we just set a goal and do what we can to meet it and if we lose or gain 2% power then we live with it.... it's not going to cost most of us any races anyway.

[pandrade]

from the get go i knew there was alot of thought put into exhsuast but my knoladge is in race bikes. in my vintage race bike world sound is no issue so i can mathematicly desighn exhsaust for max performance that usualy are way to loud and not very refined. i can mess whith open mega phones,length, and specific back pressures but in auto motive( especialy turbo systems) im not very well versed.thats one more reson i apprichiate the help


[QUOTEExhaust and intake systems are like a wind or brass instrument][/QUOTE]

and thats why i belive yamaha has the BEST sounding exhsaust tone on the market, they have and understanding of insturments and raceing lol