Installed a new system

true dual exhaust

my setup:
test pipes
x flow y pipe

Followed by midpipes then rear section mufflers

when car is parked revving hissing occurs when the car decelerates, sounds like it ls coming from the y pipe x pipe area.

When accelerating between 2500 and 3000 rpms there is a hissing/squeaking noise and this happeneds when decelerating as well same rpms

could the sound be coming due to the flex joints? Or the x pipe?

Please submit your thoughts as I want to get rid of the sound asap
when I have I will post a vid....

 

from my understanding the hissing comes from your test pipes? just from what ive read in the past posts about it before, my hissing happenes during neutral and just idling, ive got Titek test pipes and HKS true dual.

 

It could be the test pipes. But mine happeneds when accelerating and decelerating. At idle it doesn't make the hissing sound.

Last night I was cruising in 6th going 75 or so and accelerated to see if it made the sound and it did. All gaskets all new so it cant be bad gaskets.

Does anybody have this problem when accelerating and decelerating?

 

How do you have a Y pipe and stil have a "true dual" setup?

 

good point! i think they call that wannabe dual

 

LOL

 

It's called a X-flow y-pipe. Obviously you've never heard of it.

Can I get some positive input or do people on here just like to post useless ****

 

With all that money you wasted on the body kit , under glow, lambo doors I'd rather have a wannabe true dual then all that useless junk.

 

I noticed the hissing when the testpipes were installed. I think it is a thinner wall so you can hear the exhaust gasses flowing (more freely) through.

 

its just your test pipes

 

But I never got this sound until I switched to a true dual setup. My old set up didn't make this noise not one bit. I'm using the same test pipes.

 

Its your test pipes. Your new setup flows a lot better so you get to hear more. End of story =).

 

I always heard that with TPs or HFCs, the flex pipes get more flow to them and expand and contract, which adds to the noise. Everyone told me that I had a leak and I did in fact have one but after fixing it and checking thoroughly, it's just something you have to live with.

 

hi yeah i have a similar problem...that hissing noise around 2K RPM but only when letting off gas. i just took a video of this noise and posted it on another forum, asking for opinions on that noise and it looks like its normal..pay close attention as i let of the gas. let me know if urs sounds like this:


i have nismo dual intakes, stillen HFC's, and the Greddy evo-2 exhaust
http://www.youtube.com/watch?v=XKEkt...er_profilepage

 

an x flow y pipe? this must be something new. Please post some pics.

Test pipes are causing the issue. The hissing is coming from your flex joints. Totally normal and its gonna happen with test pipes.

 

Snakes in the MFGD Exhaust!!!

 

hissing is a leak...


I have a leak until the car is running for like 20mins or more then things expand tighten the leaky areas...

Once I turn my car on I can feel air coming from my bolt up areas...

if you got someone to gas the car you can eliminate exactly where it's coming from

 

Your probably thinking about a different type of hiss. For the people who have test pipes usually hear a hissing noise when decelerating. When the rpms drop it happens around 2.2k rpm to around 1.8k rpm.

 

Another way to check for leaks is to let the car sit over-night, then start it and just let it idle for about 5-7minutes. Look under the car for any drips or pooling of moisture on the ground.

 

that hissing sound is coming from your flex sections, many people running test pipes/hfc's have it..