Will test pipe make exhaust louder?
 

Hey guys. I have a 5.5 gen and just got done throwing a megan racing exhaust on and its SUPER quiet (almost stock quiet). I have a cattman y pipe, intake, SSIM, nwp BOP, nwp spacers and an intake. My question is, if i got a test pipe would my exhaust increase in volume? Any tone change?

Thanks in advance for answers.

Hell ya ... it would be much louder unless you have one extra long resonator in line to reduce the drone

It may get louder a little but not by much, I went 3" Testpipe, Cattamn Headers and 3" Exhaust it is the same volume for me with the Fastcat or less noise, I was shocked when Nmex and Rammas said it will be same or quieter but tested for myself and its either the same or less...:D

Cattman headers are next, That'll make it nice and loud! and should i just go ahead and buy the megan test pipe or are ebay ones ok?

You already have headers and a 3" exhaust... I don't think your car can get any louder. :laugh:

If you scream in an empty room, you'll notice it far more than if you scream in a room full of kids all talking at the same time.

The length is the problem. As I recall the Megan is too short. Use search with keyword test pipe, many many threads should pop up with what length you need for the pipe diameter in your setup.

Do you have a Megan catback or just the megan muffler? I had a Megan oe-rs catback on my max and it was was pretty loud...

x2

I have the whole catback on and i even bought it used. So it should be louder than brand new.

IMO...adding a test pipe makes it a little raspier. At least that is what happened with my setup. Found a test pipe that had a resonator-type surface inside and no more slight rasp.

2.5" I assume? What muffler?

Op you said you have a cattman y-pipe. Do you know that the Cattman headers will not bolt up to the y-pipe you have. And that you will have to buy the header y-pipe combo because the y-pipe you have now is designed to bolt up to the stock manifolds precats.. and will not fit the headers. So you would have to sell it. Just FYI :)

The y-pipe is designed to bolt up to the OEM pre-cats, not the exhaust manifolds. Headers replace the manifolds and the pre-cats.

Whatever... of course you're right about the two different y-pipes, but it's hard to imagine why someone would sell or buy a used set of Cattman headers that doesn't include the matching y-pipe.

Should be very easy to sell that uneven Cattman y-pipe on the Org.

actually the exhaust is louder when brand new because there is no carbon build up in it then.

you want to be loud like this guy?

I have cattman headers for sale, I'd be interested in the y pipe plus cash for them

If you get a cheap test pipe expect it to sound like crap. Dont let sound affect your purchasing though as the point of an exhaust is to flow better for HP. I put on an uneven Cattman Y on my 4th knowing it wouldn't yield the best sound but also knowing it would yield HP. Thats is my goal. When you start down the road to getting the "perfect" tone the only thing you are assured of is a headache and a lighter wallet

Can put a Bigger Resonator and get more quiet like CMAX did, but maybe a little down the road....:D

Most 5th gen test pipes are an inch too long. Use a 4th gen or 240sx test pipe.

Yep, that would do it. Cmax and Sparks (remember Sparks :laugh:) are two members here that were pretty serious about tuning their exhaust to a particular, personal taste.

Over on the G forum, the resonated test pipes and resonated HFCs are getting more and more popular lately.

Resonated high flow cat, FMFS, that's an oxymoron IMO.

I've been through 6 different exhaust set-ups with mt VQ30, and 7 different set ups with my VQ35.


People who have been doing this for a while, know from experience that a test pipe on a vQ30 or VQ35 coupled with headers and a 2.5" exhaust makes it very loud/obnoxious/raspy.

This is not the case with the VQ35 and 3" test pipe and 3" exhaust, it actually gets quieter. Sparks noted that, I noted that, Rods noted that, Ranmas noted that, and IIRC one more member noted.

I had a 2.5" test pipe on my 3" set-up and it had a not very good sound, though it did gain me some good power, and was slightly quieter than with the fastcat. Anyhow, the 3" test pipe made it sound so much better, no rasp/rattle, etc, and it was actually quieter.

So, if you have headers and a 2.5" exhaust, yes, it will make it louder, even if it's resonated. If you've got a 3" exhaust, no, it will not if you get a 3" test pipe.

OT because it doesn't exist for the Max, however...

...RHFC and RTP is where the G's are going lately. ;)

http://www.fastintentions.com/images...8-image131.jpg

Well my plan was going headers anyway, so the sound can wait until then. I still have a big mod list to fill this spring! Once i get those headers ill worry about dialing in my tone/volume. No sense in trying to "tune" my exhaust unless its complete. About the video, not THAT loud but I'd still like to have some volume lol. And 97maximachief PM me about the headers.

Don't remember what Sparks use to run, but when I want to be more quieter will do what Cmax did or buy one from him...:D

What did he do? Longest resonator possible?

Now it makes sense. Just seems kinda weird/overkill/counter productive to have high flow cats that are resonated. Cats "resonate/kill sound enough on their own, no need for extra quietening/etc.

But, after visiting that site, I see the idea.

HFC's WITH resonated test pipes.

Basically, these give you HFC's, and also remove the main cats with a TP. That's better.

Manny, there is no "main cat" on the G, just two cats each immediately after the headers. Imagine the 5.5 gen set-up, but without the main cat. (And with shorty headers instead of an exhaust manifold.)

what about just a gutted cat mixed with gutted precats 3" piping to a flowmaster? would that make it louder, raspier, deeper or just obnaxious?

Ahh, so what's happening here, is that there are the stock shorty headers, no pre cats involved, and then cats after these alleged shorties?

And these pipes, add/retain cat functionality and remove the 2 cats post shorty, but add in HFC's where the shorties were?

http://www.fastintentions.com/produc...products_id=35


Or maybe it just adds a larger resonator where the OEM cat used to be, in addition to a less restrictive HFC. As you can see, I'm doing some research on the 370z, in my case.

You're close. The shorties stay right where they are. The aftermarket cats (resonated or non) simply replace the OEM cats.

Pretty sure the 370Z is the exact same. Well, the muffler arrangement is different from the G-Sedan, but otherwise, it's the same exhaust. You'll see.

Hmm... here, this diagram explains it:

http://images.whisystems.com/smartpa....jpg_V16N9.jpg

That pic annoys me, G37 w/ 3.5L eng.

:laugh: I noticed that, too. And the hand-drawn parts are kind of comical. However, it's fairly accurate overall, giving a decent representation of the exhaust components on the G37 Sedan. The 370Z and G37 Coupe are almost identical, except for the muffler section.

Truth be told, (because I'm not proud) I bought my car without understanding the exhaust. I was rather shocked to discover the exhaust manifolds were actually headers.