Keeping the NAs quite is a bit harder, especially when there is a header involved. In my opinion anyway, it is far more important to have a reasonable exhaust note in an NA. After all, almost every NA 13B is making less then 200HP, so what excuse does it have to be loud? My 500HP 13B is only a bit louder then the Racing Beat REVII exhaust, just so you have a frame of reference and see where I am coming from. Loud can be fun for a little while, then it just gets on everyone's nerves.

If you want to keep the car quiet, running multiple resonators is the key. For NA, I'd suggest two resonators like the Vibrant Ultra Quiet in the midpipe. Then in each branch of the "Y" pipe, place a Vibrant 12" Bottle resonator. Then you can use any reasonable muffler and still have a very tolerable car. Even better is an offset muffler, though they should be sized larger (3") as they don't flow as well as the flow through mufflers. Yeah, this is a lot of resonators, but it will still weigh less then the stock cats and they won't really hurt flow.

 

Im either removing the cats or getting some racing beat headers, eaither way should make for a little more noise,
cops dont really do much ive been pulled over quite a few times already in my truck for noise they just tell me to get it fixed and see if im drunk haha

 

when i get my headers im going to use a resonator to connect it to the existing pipe. since obviously a header will increase sound and its alrdy loud and is that 500 rwhp or base and is that a t2 or NA?

 

Yeah with headers and a straight pipe back i can imagine that being a little loud

 

Sorry, should have mentioned. This is a bridgeported turbocharged NA engine, and that's 500 wheel HP. Now, obviously the turbo quiets it down a lot, but keep in mind that it is bridgeported. If my bridgeported 500HP RX-7 can be decently quiet, then there is no excuse for a stock port sub 200HP NA to be loud.

Here's a little video giving you an idea of the exhaust note:
http://www.youtube.com/watch?v=cEDp20F0R-c

 

is that a 20b?

 

As I mentioned earlier in this thread, it is a 13B.

 

unbolt pipe from manifold
install earplugs
proceed to go deaf after 10 minutes of driving


honestly.....why? have you ever heard these engines without some kind of muffling? i had to drive mine for a few days when my precat broke off the manifold, and it sounds absolutely ridiculous and horrible. chop the cat out, leave the OEM style mufflers, and its a nice sound with a decent sound increase without being completely embarassing and harsh.

 

RICE ALERT!

Slow car- check

Loud exhaust- check

 

I've got a racing beat header I would sell ya, 175 plus shipping if you're interested, it's used but it's still turning blue, hasn't been used much. Lemme know.

edit: Aaron Cake, THANK YOU for that link to the resonators, I've been looking for an economically priced 3" inlet/outlet resonator. Do you run just a resonator and a muffler on your car? I'm doing a HBP turbo build and I hated the sound of a straight pipe in place of the cat and all I had was a thermal exhaust muffler to quiet it down behind the stock twins and the rasp was horrible.

 

if thats a 13b whats with the intake.(im talking about the uim) its turbo right? or is it NA. sorry the uim looks 4 ported and im new as hell to any engine but the s4 13b NA.

 

Looks to be a custom manifold.

I think what he means is it is an N/A motor that has been Turbo charged. But I cannot be sure.

 

there are 2 parts to rx7 intake manifold, the upper intake manifold (UIM) and lower intake manifold (LIM) the upper intake manifold on most rx7's have only 4 runners, the LIM on 6 port cars then splits into 6 ports. That's as much as I can tell you. That does look like a custom UIM tho. Aaron did turbo an na motor.

 

As my car is a 2nd gen, it came with two mufflers out back. When I made the exhaust I maintained that. For a little while, I just had a single Vibrant 3" Ultra Quiet resonator in the midpope and it was acceptably quiet. Just this past winter I also installed a Vibrant 3" x 12" bottle style resonator in front of it to remove some slight drone at certain RPMs. It has made a huge difference and I quite enjoy the car being very quiet when cruising around. The two mufflers out back are a glass packed flow through design.

The engine is a 6 port S4 13B NA. The turbo system is custom. I used the stock lower intake manifold, and custom built an upper intake.

 

dude like people have said its not about how loud it is...its about how good its sounds if you go too loud you wont even beable to hear yourself think

 

yea today i heard this accord take off just screaming like it was racing and when i looked he was going like 20 mph.... accelerating real slow..... RICER

 

yeah i would just like it to be a little louder, the cat back i put on it did not even make much of a difference so i figure either getting rid of the cats and or adding headers would increase power a little while making it louder, and as for the wing i think all fc convertibles should have one.

 

Not of that size or style, it serves no purpose for your car. Except for decreasing your gas mileage.

 

how would it decrease gas mileage? its carbon fiber so weighs about 2 pounds and im pretty sure unless im going at least 100 its not going to have drag..and by that point i could use it

 

Stick your hand out the window at 55mph, quite a bit of drag don't ya think? And it's unnecessary at that! Just like making a car with 150hp sound like an F-18 driving 25 down the road.

Resist the rice, please.

 

A very crude and disrespectful suggestion.

Alright so you like your spoiler, fine. Your car, do whatever.

What I don't understand is if you hate the Honda's that are so loud driving around, why would you want to be like them? Then everyone is going to hate you too. I'm sure you don't want that.

 

I did say please. And ya it is my car, rotarys shoot flames with a straight pipe so i think ill do that

 

they shoot flames with a muffler and resonator too. They'll shoot flames with one cat on, but not too, they just shoot flames.

 

my na is str8 piped and before i even did the back mufflers they shot 2 inch blue domes. now they pop when i rev it to say 6-7k at idle and it blows flame domes about 5 inch around and makes a real loud pop when i let off the gas from revving it(usually the pop is when it flames) but yea its good to hear thats ok tho.

 

It's ok till the cops catch ya shootin flames!