So i know header talk has been discussed millions of times but i have never heard of a 4-1 header reducing the sound of a motor?

I have a 96 hatch with a B18C and a HKS cat-back. Originally i ran the oem exhaust manifold, but someone hacked and welded it straight to a flexpipe and then bolted to the cat-back. The flexpipe broke so i had to replace the header and have a test pipe made.

So i installed a 4-1 megan "type-r style" header, and a test pipe. For some reason the car sounds as if I installed a resonator on it. It was very loud and throaty before with the OEM 4-2-1 exhaust manifold, vtec was easy to hear, but now it is VERY quiet, even straight piped to an HKS muffler!

I don't mind it really, but am wondering if this is normal? I guess maybe i didn't realize that a 4-1 can suppress sound like this? It literally is silent when I am just cruising, and just a tad bit throaty at high rpm's...

Anyway late post, just was very curious

 

Really. Who cares if it's normal?

 

so you had a hole in your exhaust/flex pipe, replaced it and you wonder why the car is quieter?

I replaced brake pads and started wondering why the car doesnt make noises when i stop afterwards. any ideas?

 

 

In case you aren't getting the sarcasm, your exhaust isn't quieter because of the 4-1 header, it's quieter because you fixed your exhaust. You had a hole. Holes in the exhaust are loud. You fixed the hole, and now your car is quieter.

 

Firstly, the car was loud prior to the hole in the flex pipe, which is what i was comparing to. Despite driving it for all of 20 minutes with the hole, i still can tell a big difference in how quiet the sound is now compared to with the stock exhaust manifold.

Secondly, it doesn't matter if it's normal really. My concern was that i never once heard of a 4-1 header making the exhaust quieter...especially this quiet, with an HKS cat-back, the car sounds stock.

But once again, thanks Honda-Tech... Lol..

 

My 4->1 civic is louder than my 4->2->1 civic.

and I'm pretty sure the only difference is the muffler.

OP I would put money on dat hole being there longer than you thought, and it took a while for it to become noticeable enough for you to catch on

 

Having driven with holes in the exhaust before, you'd be surprised how much noise leaky pot-metal makes.

Flex pipes also don't keep pressure like they should.

I'm not understanding if this is a real concern because your car is actually quieter or you just wanted to start a thread discussing 'omg quiet cars, who'da thunk?!'

 

in a way yes it possible the header made a noise diffrence since the exhaust gas flow was smoothed out compared to stock manifold were it scatters more