RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   Racing Beat without the presilencer (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/racing-beat-without-presilencer-752221/)

SleepeR1st 04-28-08 10:16 PM

Racing Beat without the presilencer
 
Does anyone know of any videos out there of the turbo back, catless, racing beat exhaust WITHOUT the presilencer and just a straight pipe there? I'm curious as to what the car would sound like, thanks!

13bturbofc 04-28-08 10:24 PM

im also interested in how much of a difference it would make

RotaryRocket88 04-29-08 12:53 AM

A video will give you an idea of what the exhaust tone is like, but the overall loudness can't be demonstrated (volume controls). My corksport presilencer/resonator is about half the length of RB's, but it sounds 100x better than when I had a straight pipe. The tone is so much cleaner, and it is far quieter at partial throttle/low rpm. It still screams up to redline, but it keeps it from sounding like I'm trying to race from every stoplight.

SpeedOfLife 04-29-08 01:34 AM

I'm pretty sure that presilencer is just a stainless steel packed tube, no real restriction there...

13bturbofc 04-29-08 07:14 AM

yeah you can see straight thru it but it still would quiet it down right?

SpeedOfLife 04-29-08 06:27 PM


Originally Posted by 13bturbofc (Post 8143123)
yeah you can see straight thru it but it still would quiet it down right?

Yeah, that's exactly the point of it. I'll compare the concept of a glass pack (or steel pack in the RB case) with a straight pipe of the same length:
Straight pipe:
-Very little restriction
-Lightweight
-Loud as hell, and obnoxious sounding

Pack:
-Very little restriction
-Not as lightweight
-Quiets things down and will also typically add sound quality

The RB exhaust is intended for power yet use on the street. If you want the most power and to heck with the sound you don't need a straight pipe anyway, you simply need an open dump soon after the turbo (or header if you're NA). There are ways to tune a race exhaust but for most of us I'm sure it makes little difference even for fairly dedicated weekend warriors.

Now, if you need something really cheap but quiet enough to avoid police attention then you get a straight pipe with some mufflers. That's basically what I've done, except the PO provided the back half. They installed new mufflers and a y-pipe (not stock, but mimicking closely). I pulled the cats, installed a dp and flex where a presilencer would go, and now that my rebuild is in and I installed new gaskets it's fairly quiet and sounds BEAUTIFUL. It will scream at WOT, but cruising it's not bad. I'm very pleased, and it was pretty cheap having done all the work myself.

Brody8877 04-29-08 07:18 PM


Originally Posted by SpeedOfLife (Post 8142858)
I'm pretty sure that presilencer is just a stainless steel packed tube, no real restriction there...


It is.

Just imagine it as a 3rd muffler piece.

13bturbofc 04-29-08 08:26 PM

all i know is i have the rb exhaust and its way to quiet even with 400whp. i like to be able to at least hear it running at idle...lol so I'm gonna make a pipe to remove the presilencer.

SpeedOfLife 04-29-08 10:02 PM


Originally Posted by 13bturbofc (Post 8145503)
all i know is i have the rb exhaust and its way to quiet even with 400whp. i like to be able to at least hear it running at idle...lol so I'm gonna make a pipe to remove the presilencer.

Couldn't you just raise your idle to 1k? lol Their systems are so nice I'd hate to see it torn apart like that.

13bturbofc 04-29-08 11:17 PM

it is a really nice system just not loud enough. and im not really going to be tearing it up. id take it to an exhaust shop and have them make a pipe with flanges so i can just take it off and put the presilencer back on if i ever wanted to. trust me im not stupid enough to hack up a beautiful 800$ exhaust lol

SpeedOfLife 04-29-08 11:21 PM

I would suggest perhaps using some flex in there if you do remove the presilencer. While it would still be loud and flow well, it should transmit less noise directly into the car's structure (more comfortable) and be easier on the turbo/manifold. I had issues with my turbo coming loose, I think due to both a torn motor mount and stiff exhaust pipes that must have been applying pressure back and forth all the time.

Sgt. Pepper 04-29-08 11:22 PM


Originally Posted by 13bturbofc (Post 8146104)
it is a really nice system just not loud enough. and im not really going to be tearing it up. id take it to an exhaust shop and have them make a pipe with flanges so i can just take it off and put the presilencer back on if i ever wanted to. trust me im not stupid enough to hack up a beautiful 800$ exhaust lol

I'm the same way. Have the full RB NA exhaust on my car but it's too quiet at idle, can't even hear it. I've been thinking about putting a straight pipe in place of the RB pre-silencer like you and hope it's not too loud. it shouldn't be with those heavy racing beat mufflers

arghx 04-29-08 11:26 PM


Originally Posted by 13bturbofc (Post 8145503)
all i know is i have the rb exhaust and its way to quiet even with 400whp. i like to be able to at least hear it running at idle...lol so I'm gonna make a pipe to remove the presilencer.

I have the 3" RB catback, with a custom 1 piece downpipe (no presilencer or cat). It is plenty loud... and when the wastegate opens up to atmosphere, it is unadulterated.

13bturbofc 04-30-08 05:32 PM


Originally Posted by arghx (Post 8146132)
I have the 3" RB catback, with a custom 1 piece downpipe (no presilencer or cat). It is plenty loud... and when the wastegate opens up to atmosphere, it is unadulterated.


:lol: yeah i have a greddy type R 47mm wastegate wide open i dont even have a dump tube. scares the shit outta people when it opens. but when im just cruising around or at idle the exhaust is way to quiet. i was also wondering how i can get that turbo sound coming thru the exhaust ya know like when you hear it spool thru the exhaust. im assuming that would take a straight exhaust with no mufflers? ya know like how a SRT-4 has a turbo thats the size of a pocket watch but you can hear the turbo so loud thru the exhaust. that sounds bad ass.

*edit* cant believe i just said i like something about an SRT-4 lol


All times are GMT -5. The time now is 06:11 AM.


© 2024 MH Sub I, LLC dba Internet Brands