Exhaust is going down hill!

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MaineExport
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Exhaust is going down hill!

Postby MaineExport » Thu Jul 25, 2002 4:42 pm

Ok... I know this was discussed on the old boards, but I never payed attention, because I didn't have a problem. The exhaust on my 95 is turning to crap! The muffler is rusting through, and there is some rattling between 2000 and 3000 RPM's. First off, what is rattling, (sounds like the cat?), and secondly, for a N/A KA what is better, the N1 or N1 dual? If the cat is shot, what are my options in the aftermarket? Also, is the HKS a better set-up for possible future turbo applications? (I already have a GReddy header that will have to go) Thanks, Greg.


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AunVoh
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Postby AunVoh » Thu Jul 25, 2002 4:42 pm

um, for the muffler the best kind of a muffler is not have one :) i haven't had a muffler in a long time, no tickets and it's not that loud, it took off like 30 pounds of muffler weight too. and if your cat's bad i'd just put a dump pipe in ;)

trpower7
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Postby trpower7 » Thu Jul 25, 2002 4:42 pm

The rattling is your exhaust heat shield, it bolts to the bottom of the functional and "dummy" cat. Just crawl under the car and take it off, it really has no function except to keep you from burning tall grass if you should park in it. For exhaust, I would say take a walk down to your local exhaust shop and do one of two things. If you are going to go turbo in the future, buy a muffler of your choice (flowmaster 60 series is good ($100)) and get them to make you a 3-inch cat-back and put the muffler on the end. Grab some nice tips, and you are ready to roll. This should run you about $250 all said and done (flowmaster+work = $250). If you don't want to go turbo just make that a 2 and a half inch pipe instead of 3 inch. Random Technologies seem to make the best hi-flow cat on the market, I think it will run you around $200. There is NO SENSE in spending $400 on the Apexi system (except bragging rights) when the same thing can be made for $150 less. And if you plan to stay non-turbo you can use that $150 to go toward your HotShot header. If you go HotShot, RandomTech, 2.5 inch back to Flowmaster, you would come right at around $800. Not bad for a COMPLETE exhaust system from the time the exhaust comes out of the valve now is it? Hope this was helpful!!

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aleph1
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Postby aleph1 » Thu Jul 25, 2002 4:42 pm

Its not always the heatsheild. I bolted mine down fine and I still hear a rattling noise, and I get whistling, both from I believe the exhaust/cat.

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GodDrivesA240sx
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Re: Exhaust is going down hill!

Postby GodDrivesA240sx » Thu Jul 25, 2002 4:42 pm

maineimport wrote:Ok... I know this was discussed on the old boards, but I never payed attention, because I didn't have a problem. The exhaust on my 95 is turning to crap! The muffler is rusting through, and there is some rattling between 2000 and 3000 RPM's. First off, what is rattling, (sounds like the cat?), and secondly, for a N/A KA what is better, the N1 or N1 dual? If the cat is shot, what are my options in the aftermarket? Also, is the HKS a better set-up for possible future turbo applications? (I already have a GReddy header that will have to go) Thanks, Greg.
My 95 had a rattle that was comming from around the cat. I took the heatshield off but the rattle stayed. Then I took the cat off and saw that all the platinum had dissappeared (apprently it was blown out of the exhaust, or is still chilling in my muffler) So instead of buying a new cat, which I didn't have the money for, I just got a straight pipe off ebay for 35 dollars. Once I put the pipe on the noise vanished, and I finally got to enjoy my greddy exhaust sound for the first time! Damn it sounds, sweet nice low rumble, and if you let off the gas - quiet. Hope that helps.

:freak

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GodDrivesA240sx
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Postby GodDrivesA240sx » Thu Jul 25, 2002 4:42 pm

aleph1 wrote:Its not always the heatsheild. I bolted mine down fine and I still hear a rattling noise, and I get whistling, both from I believe the exhaust/cat.
Yeah, check out my above post, the whistling is from the air swirling around inside the hollow cat, atleast that's all I can figure.

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1991240xs
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cat

Postby 1991240xs » Thu Jul 25, 2002 4:42 pm

sounds like someone might have tried to gut your cat already or it's just falling apart...the whistling/rattling could be the air swirling around in the cat-

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aleph1
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Postby aleph1 » Thu Jul 25, 2002 4:42 pm

I think Ill get a test pipe aswell, I dont have enough money for a new cat, and i just got it smogged like the beginning of june.

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MaineExport
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Postby MaineExport » Thu Jul 25, 2002 4:42 pm

Thankfully Maine doesn't concern themselves with emissions, so a test pipe it will be!! As for the cat-back, still open for suggestions, thanks.

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Postby Nismo_Freak » Thu Jul 25, 2002 4:42 pm

HKS Exhausts are designed for the N/a KA and have smaller piping, 60-70mm for the Dragger and 60mm for the Hiper, if I remember right. Where as the N1 dual and N1 set ups can be bought in the 3" diameter size if you go CA/SR/KA-T later on but will be louder than hell, especially with a header, on the N/a KA.

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How much does a new cat cost?

Postby Metal240 » Thu Jul 25, 2002 4:42 pm

I think either my heat sheild is rattling, or it's my cat. When i idle, i dont have the rattle but like the other guy, around 2-3krpm u can really hear it rattle.

Just incase if i have to buy a new/used cat, how much will this cost me?

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k6kicker
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Postby k6kicker » Thu Jul 25, 2002 4:42 pm

you think your exhuast is bad, my muffler is so far gone that it spits out what looks like steel wool from the tip, but its going in for a cheap (aka bent at the shop 2.5 stainless pipes and a flowmaster) fix soon

hotshot240sx
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Postby hotshot240sx » Thu Jul 25, 2002 4:42 pm

high flow cat would be an option...difference mostly in high end...the n1 is a good muffler but HKS is by far..way better in sound...but all KA's sound rough so also think about a resignator as well. hotshot headers would be a good header...and a nice intake would help you sound smoother as well!

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aspinballer
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Postby aspinballer » Thu Jul 25, 2002 4:42 pm

unless they check emissions where you live, just lose the entire cat.and if you remove the resonator, you get a lot of popping sounds when you drop from over 3k

180fan
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Postby 180fan » Thu Jul 25, 2002 4:42 pm

You could also opt for a GP exhaust. Those are awesome. Had one, someone stole it...now I've got a 5zigen pro racer. It's good with the gains overall and was dyno proven too. But, I still like the design and sound of the GP's so I've got a Spec II Pro on its way from Japan. Touge factory says the Pro line from GP's are rated at a very quiet 89dB. Also try the 5zigen border 3 or the blitz realize tt. those are very quiet. The blitz is also 80mm while the 5zigen is 70 or 75mm?


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