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-   -   What exhaust do most single guys run?? (https://www.rx7club.com/single-turbo-rx-7s-23/what-exhaust-do-most-single-guys-run-131487/)

94SR2 11-09-02 03:43 PM

What exhaust do most single guys run??
 
I just swapped out my exhaust for a RB dual tip- one, for the non-rice look, and second, for the noise. However my car feels much slower? and I'm not talking 2-3 hp slower. I mean the lag has seemed to increased as well as the overall kick-in-ass-feel. I just couldn't take the loud drone on the highway as well as the deafening echo through the local streets at night (Cops now know me . :( )
But if this is the result I'm wondering if it was worth the loss. I'm going to re-dyno on wed. at the same setup as last time to see if this is true. if it is gotta figure something out...


ed

maxcooper 11-09-02 04:33 PM

I have always wondered how much HP the noise reduction and subtle looks cost. But it would have to be pretty huge to get me to switch back to a big noisy one. A dyno test is a good idea, since the difference in noise can bias butt-dyno results.

If you find that the difference is large, perhaps a higher flowing cat back with a quiet muffler in the midpipe would yield better results. I want the car quiet(er), so I am going for the RB dual tip and a quiet muffler. ;)

Do you have the new dual tip or an older one? I think the ones that RB has been selling for the last year or two flow better than the ones from several years ago. I have one of the older ones, but I would consider a switch to the newer one if it is proven to make more power on the dyno. I know that isn't the aim of your test, but maybe I can borrow one to dyno test on my car from someone local to me.

-Max

rotorbrain 11-10-02 02:15 AM

does it really matter what exhaust you run if youre single or not? are you not aloud certain exhausts if you have a girlfriend? haha, jk. . . im a dweeb.

paul

maxcooper 11-10-02 02:53 AM

Single guys probably run the exhaust straight thru... no wife would allow it, and no girlfriend would put up with it. ;-)

-Max

The_Ego 11-10-02 03:07 AM

Im running a 3" mandrel bent system straight off the turbo, no cat, 1 resonator and an HKS SuperDragger muffler with 5" tip, it sounds nice, not overly loud at all.

94SR2 11-10-02 02:27 PM

Max,
I'm running the newest dual tip from RB as well as a resonated midpipe (straight thru magnaflow). Quiet is also the key for me as well being a "sleeper" but it all depends since I don't drive my car more that 3K a year. I know the torque/hp curve moved from where it was but peak to me is also important. It was this or the HKS Hiper Ti system but I just don't know anymore.

-Ed

nocab72 11-10-02 03:08 PM

94SR2 - I know what you mean, not 2- 3 rwhp. Just the difference between silencer in and silencer out with my JIC Bullet is about 40 - 50rwhp!!!

10psi on GT35/40 with silencer in, Powermeter says 330rwhp.
10psi on GT35/40 with silencer out, Powermeter says 380rwhp.

I've duplicated this several times, in/out/in/out in the same evening... it stays OUT now! :D

K

94SR2 11-10-02 03:26 PM

HOLY SHIT!

94SR2 11-10-02 03:33 PM

I think I'm going to put in a cable driven Y dump on the Left side (if possible) so I can open it up when the situation calls for it. I had this on my Grand National and it made driving the car (which was daily for a while) possible withOUT having to lose the occisional race.

I'm NOT going to give up 40 or 50 HP!

-Ed

AJC13B 11-10-02 04:07 PM

As big as I can fit :D

3 inch off the back of the turbo, 1 resonator and a custom made 3 inch muffler. Pretty loud (108db @ 3500rpm :D ) but does the job

maxcooper 11-10-02 08:08 PM


Originally posted by 94SR2
I think I'm going to put in a cable driven Y dump on the Left side (if possible) so I can open it up when the situation calls for it. I had this on my Grand National and it made driving the car (which was daily for a while) possible withOUT having to lose the occisional race.

I'm NOT going to give up 40 or 50 HP!

-Ed

I saw some electrically-operated valves that looked they could be fun for some exhaust projects. http://www.quicktimeperformance.com/qtec.htm

I've got a bunch of ideas for these, here are a few:
- RPM switch actuated
- WOT switch actuated
- regular cut-out
- Dual pipe midpipe - primary muffled, secondary switched and unmuffled
- Modify cut-out so the "closed" position is half-open and install it inline in 3" muffled mid-pipe, open for full flow & noise

-Max

94SR2 11-10-02 09:12 PM

SWEET!...Max, you da man.
That's exactly what I was looking for. What I plan to make is system that's split at midpipe. I'm gonna try to run a 3-3.5" pipe on the driver's side (mirror of the current route) to the tail end of the car. So in the end all anyone will see is two DualTips (left-open and right-RB muffler). Still looks stock but won't light my carpet on fire (long story...lol)

Seems like a lot of work...but I don't see any alt's at this point except to buy another exhaust :(, again.

-ed

vosko 11-11-02 09:37 AM

i'm running the racing beat catback on my FD. i like it alot. i also have an atmosphere vented wastegate so it's quiet driving around and loud as hell when i get on boost. just the way it should be :)

nocab72 11-11-02 09:48 AM

I'm sure the restrictive exhaust is more noticable with my setup (opposed to yours vosko) as my wastegate dumps back into my DP.

K

Maxthe7man 11-11-02 09:48 AM

Is the RB muffler a straight through resonator type or multi chamber baffle type muffler? I noticed the same type of increase, when I changed from baffle type mufflers to straight through resonator core mufflers, all though the car didn't really get any louder, just deeper sounding, and you are right its not a 2-3 hp difference, its a big difference in power and in spool time on a turbo car..Max

94SR2 11-11-02 01:26 PM

Th RB dual is written up on their website as a straight through type but it's size and noise reduction tell me it's not. However it's losing it's appeal the more I drive the car.

vosko 11-11-02 01:33 PM


Originally posted by nocab72
I'm sure the restrictive exhaust is more noticable with my setup (opposed to yours vosko) as my wastegate dumps back into my DP.

K

i concur. i like open wastegate scares everything on the road in a 1/2 mile radius :D

silver93t's car has the greddy PE it sounds really nice. i'm not gonna change my exhaust till it wears out. my car is the super sleeper :D

SPOautos 11-11-02 04:22 PM

I dont think the RB would have the same kind of lossos as a JIC Bullet with the silencer in. Those silencers make a huge difference in power. I dont think the RB would have that much loss. It would be interesting for someone to dyno it and find out though.

I have the RB and as long as I make some power I'm fine. I just cant have a car so loud I dont enjoy it, been there, done that. It takes the enjoyment out of the car for me. Also, with intake, and dp, resonated mp, and Pettit cat back which everyone says is RB, I ran 12.3@113 which translates into 330-340, I was at 12ish prob of boost on stock seq system and stock engine with a PFC base map.

It cant be THAT restictive....maybe in the higher hp levels it becomes more restictive though

STEPHEN

nocab72 11-11-02 04:31 PM

Max & 94SR2 - One thing I want to warn about...I saw AFR's nearly a point difference between Silencer IN and Silencer OUT, (leaner with it out as it was flowing more air), so tune with your "cutout" open ... (or silencer out).

I about $hit when I was tuned for 11.2 with the silencer in, pulled it out and saw 12.2!!! (I'm sure that is where part of the 40 - 50 rwhp came from).

K

94SR2 11-11-02 04:43 PM

Thanks for the info nocab72....So maybe I'm running too rich now so that could account for my power drop. If this is true...I can't switch maps with a cutout.

-Ed

nocab72 11-11-02 04:50 PM

It's sooo nice to have a datalogit and DIY wideband...

I just don't have too many passengers because my laptop takes "the other" front seat. :D

K

vosko 11-11-02 04:55 PM

i dyno'd 416RWHP @ 13psi with the racingbeat catback. GOOD ENOUGH FOR ME !!!! :)

94SR2 11-11-02 10:28 PM

Goal: 440rwhp@17-20psi, on pump gas by Jan. 1st 2003.
with racingbeat...but It will get dumped if it stops me.

vosko 11-11-02 10:38 PM

17-20 on pump gas ??? no race gas ? lol

94SR2 11-12-02 08:33 PM

no, PUMP gas...


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