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Quieting down Berk HFC's + Nismo catback?

Hey guys,

Last week I installed Berk HFC's as preparation for my Vortech Supercharger project and now I feel my Nismo catback is too loud.

I loved the way the Nismo sounded with the OEM cats but I need the extra flow of the Berk HFC's for the supercharger. I don't want to get rid of the Nismo either as I love the sound and look of it.

What are my options to quiet down my exhaust system without losing too much flow?

I'm thinking an extra resonator in the mid-pipe will be the best and cheapest option but I'm no exhaust expert (:

Thnx!

like i said

Quote:

Originally Posted by scenehouser (Post 8911125)

I loved the way the Nismo sounded with the OEM cats but I need the extra flow of the Berk HFC's for the supercharger. I don't want to get rid of the Nismo either as I love the sound and look of it.

u cant have both. if u wanna tear up your exhaust to put a extra res which wont do much then try it.

you can sound dead your car. i used edead and some dynamat well not really dynamat but something close to it made by the same people who make edead.

im always amazed at people who say their nismo exhaust is way too loud. I really want to hear one...

btw, the supercharger will only make the exhaust louder. So I guess your ONLY option is adding a muffler or resonator somewhere on there, since you don't want to take the hfc off. So if thats the only route you want to take, why even ask on here.

i was asking for advice because maybe i had overlooked an alternative... and i have.. i just found this motordyne xyz pipe with resonator:

http://www.motordyneengineering.com/...Z_pipe_032.jpg

does anyone have experience with this resonated y-pipe?

A resonator is going to do sod all to quiten the exhaust. If you want it quieter you need to add an extra muffler. But then, your exhaust wont sound the same. Catch 22.

Do you have the original exhaust? There you go.

Quote:

Originally Posted by scenehouser (Post 8911431)

that's what I wad going to suggest. Great, high quality piece.

if u are in fact going SC and not dreaming i would advise you to go with the HFC module for the XYZ. I believe another member made 25+hp with the HFC module bc of the backpressure it built for the SC

i had resonated test pipes with nismo and it wasn't as loud as some other exhaust on the Z with oem.

i have the md resonator, hfc and nismo exhaust. its still somewhat loud. you can't have the best of both worlds.

fyi, before this, i had a straight pipe, jic y pipe and jic single exhaust. that **** was loud. what u have is crackers.

Quote:

Originally Posted by plumpzz (Post 8911568)

i have the md resonator, hfc and nismo exhaust. its still somewhat loud. you can't have the best of both worlds.

fyi, before this, i had a straight pipe, jic y pipe and jic single exhaust. that **** was loud. what u have is crackers.

he doesnt understand. Lol just put as many res and mufflers u can under there:thumbup:

thnx guys.. it's not like i want it silent or anything but maybe a bit less annoying humm when driving 2500-3000 rpm on the highway would be nice.

Quote:

Originally Posted by 2004Black350z (Post 8911480)

if u are in fact going SC and not dreaming i would advise you to go with the HFC module for the XYZ. I believe another member made 25+hp with the HFC module bc of the backpressure it built for the SC

Next time just relay the results of the other member's mods instead offering an explanation and opinion (b/c it'll most likely be wrong). This seems to be a pattern with you. Stop handing out advice when you don't know what you're talking about.

Why exactly should he go with an HFC module? Why does he need another cat? Doesn't that negate the purpose of installing HFCs in place of stock cats? He wants more flow and less restriction, thus HIGH flow cats.

Back pressure does not make power. Suggesting that he should slap on another cat, and one that's supposed to be more of a band-aid than a true emissions device, is absolutely idiotic. Moreover, F/I cars work best with NO back pressure.

By definition, back pressure impedes exhaust pulses. The goal of a good exhaust, and why the XYZ module makes good power, is to maximize exhaust gas velocity and scavenging with as little back pressure as possible. The XYZ collector is ideal, in terms of its construction/size/measurements, for this purpose. The rest of the exhaust is just there to manage pressure drop.

OP, DO get an XYZ pipe, but get the resonator section (if you must), not the cat section. The resonator won't make a HUGE difference in sound, but the XYZ pipe will yield hp gains.

Quote:

Originally Posted by 03basesedan (Post 8912348)

Next time just relay the results of the other member's mods instead offering an explanation and opinion (b/c it'll most likely be wrong). This seems to be a pattern with you. Stop handing out advice when you don't know what you're talking about.

Why exactly should he go with an HFC module? Why y
does he need another cat? Doesn't that negate the purpose of installing HFCs in place of stock cats? He wants more flow and less restriction, thus HIGH flow cats.

Back pressure does not make power. Suggesting that he should slap on another cat, and one that's supposed to be more of a band-aid than a true emissions device, is absolutely idiotic. Moreover, F/I cars work best with NO back pressure.

By definition, back pressure impedes exhaust pulses. The goal of a good exhaust, and why the XYZ module makes good power, is to maximize exhaust gas velocity and scavenging with as little back pressure as possible. The XYZ collector is ideal, in terms of its construction/size/measurements, for this purpose. The rest of the exhaust is just there to manage pressure drop.

OP, DO get an XYZ pipe, but get the resonator section (if you must), not the cat section. The resonator won't make a HUGE difference in sound, but the XYZ pipe will yield hp gains.

Wow u do have a man crush on me. Again who r u? Why r u here with a grocery getter? Obviously u have never researched anything before opening your mouth. Why would he want a hfc module? Have u read the thread that I was referring to? If not stfu. If.he wants to.turn down sound volume without hurting hp and tq for a sc the hfc module would b ideal. Please stop following my post. Im flattered but your not my type.

Quote:

Originally Posted by scenehouser (Post 8911431)

This is probably your best option for a clean sound and reduced decibals.

thnx guys i'm gonna look into the xyz-pipe with resonator