carcrazy

Ok ok ok....

After 700 miles and 3 weeks driving the RX-7 to work, my ears buzz for about 10-20 minutes after driving the car. The car is friggin' LOUD with the single turbo and street port - I mean deep resonating sound and just loud. We have the HKS exhaust (not the loudest). We have a Random cat also (no, not running without a cat for the 12 inch flame shooting out the back when coming off the freeway at 5000 rpm).
So, here is the weird question, anyone had this problem with a loud exhaust and wanted a more quiet exhaust? What exhaust offers a "mellow" exhaust tone that is also easy on your dyno numbers that you spent $$$ to get that last 20 hp? Lastly, this will end up, after the breakin, my wife's car.

Any help or suggestions would be great.

Rick
1993 RX-7 Project

Evil Aviator

How is the wastegate integrated into the exhaust system?

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88 RX-7 20B/T66 Money Pit
88 RX-7 TII Daily Driver
84 RX-7 GS Driving School Beater
00 F-150 Recovery Vehicle

Cheuk in Seoul

Mine is also very noisy.
Street port, APEXi single, Trust cat back.
I spend $$ to get a Random Tech cat to make it quieter but it had minimal effect.

My neighbors constantly complain and I idle in neutral when I'm around cops.

Cheuk

RX-7 Pilot

Got the same problem here too!! I am considering buying the petitt resognated mid-pipe but dont really know if this will help. Isnt the racing beat exhaust restrictive as compared to the "canister" type mufflers?

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93 RX-7 R1
Apex single turbo
Apex dual N1
Apex AVC-R
Apex PFC
custom SMIC
HKS SS BOV
unorthodox pulley
1200cc secondaries
nippondenso fuel pump

HWO

if your car has carpet in it - what are you worrying about, i have a 3inch exhuast from the turbo back, with one muffler, no cats, no resonators, no carpet, next to no sound deadening at all - its glorious, can listen to those oh so sweet tunes it plays all trip long.

Try wrapping your exhuast in fibreglass tape/ heat wrap, a lot of exhuast noise actually comes out the side of the pipe, more so with Stainless systems because they have thinner wall thickness than mild steel exhuast systems.

all i can say is you wife must be a real rotor nut if she is going to be cruising in a ported, single turbo FD to work and back or whatever.

tristarx

I can live with some HP loss with my RB catback and enjoy my MP3 player.

Loved it, will never change unless I am a pure drag racer.




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Wayne
93 CYM R1
86 MR2 N/A
www.geocities.com/tristarx

FD_Pilot

iTrader: (1)

I posted this a few weeks ago...

I was at VIR.... there were two 3rd Gens there....

One non-sequential (blocking plates...ported WG...ported motor, no cats) and a T-78 (Borla XR-1 silencer + PFS catback)


The T-78 was significantly quieter at idle and part throttle (around the paddock)...at speed it would be hard to say...which was louder...the T-78 was just as loud as the Viper GTS coming down the straight next to the North Course paddock...

I know the guy with the non-seq car, I've got a 3rd gen, and there was another 3rd gen owner there... and we all agreed that the T-78 with the silencer was a lot quieter...

The DP from the turbo was also wrapped on the T-78 car...I don't know if the wrapping went all the way over the silencer or not.



[This message has been edited by FD_Pilot (edited March 15, 2001).]

carcrazy

This "sounds" interesting... j/k

My "big-***" wastegate does vent to the exhaust. The real issue is the nice stereo she has in the car - drowned out. The sound out of the rear of the exhaust is a deep rumble. For a track car or a weekend car, this would be awesome. For her, she likes the soundz, but after a while it does get to you jetting around town.
If this is what to expect and live with for this rotary monster - so be it!!!
I gotta say this is more fun to drive than the 911 Turbo!!! That is saying a lot. The nice little sounds the motor makes now are awesome!
Does ceramic coating the manifold, turbo exhaust housing, and down-pipe have any affect on the sound? This was done also.

regards and thank you!

Ricky
1993 RX-7 Project

HWO

it would have some effect but it would be cheaper and probably quieter to use fibreglass tape or heat wrap to achieve the same thing.

carcrazy

Has anyone ran without wrap on their exhaust, then wrapped and noticed a difference? I would be willing to wrap the entire exhaust from the downpipe back. It actually sounds like the walls of the pipe are making the noise as well. This may be a good solution. Let me know if anyone has tried this.

Rick
1993 RX-7

HWO

it makes it quieter inside i did it myself, fromt the turbo to the bend at the rear suspension where it goes under the subframe.

silver3rdgen

I was the NS 3rd gen at VIR a few weeks ago (see above). The T-78 guy was Paul Winter, he had a borla Xr-1 muffler canister welded into the MP. His car was substantially quiter than mine...and trust me, if after riding in his car, i don't think there is much/any HP loss from running it. (160+ in the straights)That car is insane!!

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Shannon Ward
94 Silver Base w/ lot o' mods (street fighter)
93 CYM R1 under construction (road course car)

silver3rdgen

Gordon,
Most likely i'll be at MADS this year, i live about 3 hours from there. The only problem is that i'm in Kansas for business. About 1000 miles each way to VIR from here.Not sure if i'm up for the drive and still be at work on that monday...pray for a day off i guess.
Oh yeah...i bought a new toy...


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Shannon Ward
94 Silver Base w/ lot o' mods (street fighter)
93 CYM R1 under construction (road course car)

BlueSprite

So, do you guys know which Exhaust will reduce the noise ???
I have Race Port and T78, Apex Duel exhaust, and it is too loud to me; i would like to know is it any exhaust will reduce a little bit atleast...... thx

I m in San Francisco, CA, the law is awful.....

thx Sindy

RexRyder

iTrader: (10)

1st page, last post:

ReDLiNe@t9

if you guys did not want your car to be loud why would you ever consider a t78.....its going to be loud...thats common sense--big *** waste gate-if your worried about not hearing your "mp3" player then sell the 7 and buy an esclade and put a system in it to be like every soccer mom and gangsta on the planet

RexRyder

iTrader: (10)

i think hes talking about a car with stock twins. but see^^ a t78 can be quiet too?

BlueSprite

Are you sure that car has STOCK TWINS in it ??? or T78 ??
I m considering about the noise that i have on my FD w/T78, it is just too loud to me. The whole street can hear my car when i start up.

I m thinking about the borla Xr-1 muffler canister or RB muffler to install on my FD to make it a little bit quiet.

BTW: i cant even talk to my frd next to the car when it started up. Instead of Muffler, is it any ways to reduce the noise ???

thx SINDY

modrx7

iTrader: (1)

I was too lazy to read the whole thread...

But, Why not just weld in an electric dump at the end of the downpipe, then just use a very restrictive quieting exhaust. That way when you wanna open it up, it will flow freely, and when you just want peace and quiet, it is quiet.

Edan

BlueSprite

what is ELECTRIC DUMP ?? where can i see the pictures ??

thx SINDY

BlueSprite

Do you guys know where i can get a "Borla XR-1 muffler canister" ???

In borla website, i only see Borla XR-1 muffler.

Do i need a catback behind the the muffler ?? is that mean i use Borla XR1 muffler canister instead of midpipe ??

maxcooper

Electrically-operated cut-out:
http://www.buickgn.com/electricexhaustcutout.htm

It won't make your exhaust any more quiet, but you could run a very quiet (and restrictive) main exhaust system and then use the cut-out when you want low-restriction (and lots of noise). The cut-out would bypass your quiet exhaust system.

One issue with this approach is that since it changes the flow of your engine system (and because the FD has a speed-density EFI system with no air flow sensor), you would ideally need two different fuel maps -- one for when the cutout is closed, and one for when it is open.

Perhaps you could wire it to open when you hit a certain boost level that you don't normally hit when driving around town. With this "automatic opening" approach, you could probably use a single fuel map.

Personally, I just want my car to be reasonably quiet all the time, and I don't want to have a cut-out.

-Max

maxcooper

It's a minor point, but "Borla XR-1 muffler canister" sounds like you just want a muffler cannister (which can be purchased separately for rebuildable racing mufflers, but not in the Borla XR-1 line). But I know that you really want a muffler, and not just the cannister.

"XR-1" is a whole Borla product line. The most popular mufflers from that line for our cars seem to be the Sportsman models. But I think the Race models are quieter. Frankly, their XR-1 line and the different names of the mufflers is pretty confusing, but this is my understanding of their names and construction. Here are two 3" center/center pipe, 16" long Borla XR-1 cannister mufflers:
http://tinyurl.com/5lzkb (Sportsman, less expnsive, stright-thru)
http://tinyurl.com/5hu8f (Race, quieter, splits flow into 3 internal pipes, but still essentially straight-thru)

You would use one of these mufflers in your midpipe and keep your normal cat-back.

-Max

BlueSprite

Well, actually i just want to turn down the noise from the exhaust because it is very loud to me. My parents and frds have been warning me about the exhaust for two weeks, so i think this is the time for me to find a better Muffler/Exhaust to reduce the noise.

In those prior posts i said "Borla XR1 muffler canister" because i see the earlier posts mention this kind of muffler canister will reduce the noise a lots. In fact, i m thinking about Borla products for my FD.

In your last post, do you mean use the borla XR1 canister muffler as a midpipe, and then keep my normal(stock) catback (Stock muffler) ??? At that point, it will reduce the noise problem ???

sindy