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-   -   DP,MP apexi w/silencers vs. DP main cat, apexi (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/dp-mp-apexi-w-silencers-vs-dp-main-cat-apexi-108774/)

overkill 08-25-02 10:42 AM

DP,MP apexi w/silencers vs. DP main cat, apexi
 
Does anyone know which is more restrictive:

(1) DP ,MP with an apexi n1 dual with the silencers in.

OR....
(2) DP, Stock main cat, Apexi N1 dual without silencers.

Also, anyone run straight-thru pipes with their apex silncers in? is it quieter than having the main cat in place? I'm thinking of geting a midpipe, but the loudness of the setup has me worried....

Leprechaun 08-25-02 10:46 AM

Run straight exhaust with a muffler welded into the midpipe. Flows the same as standard midpipe, but 100% quieter. Little more $$ though, of course.

the_saint 08-25-02 11:57 AM

I am running DP, MP (with Borla XR-1 Sportsman muffler welded in), and N1 duals (no silencers).

It is very loud. At idle it burbles like an outboard, cruising it sounds ok, and at WOT it is very very loud (Harley loud). I got the Borla welded in because without it, it sounded a bit tinny in my opinion, and it was way too loud. The cops were hounding me, and my neighbors were complaining.

The car is still loud enough to set off pretty much every car alarm in the parkade at work (which I find funny, but very noisy).

I am curious to see how the M2 duals, or RB catbacks sound however. The loudness is fine with me, but my better half doesn't like it, and it does draw a bit too much attention

thesaint

RX7Elmo 08-25-02 12:40 PM

i would think having the stock cat in place would silence things a lot more than having just silencers in.

Also, the stock cat would flow more than teh silencers would from looking at the silencers. with the N1 and the borla exhaust XR1, the car is still loud. NOt much u can do with that type of cat-back.

Danny

overkill 08-25-02 04:17 PM


Originally posted by the_saint
I am running DP, MP (with Borla XR-1 Sportsman muffler welded in), and N1 duals (no silencers).

It is very loud. At idle it burbles like an outboard, cruising it sounds ok, and at WOT it is very very loud (Harley loud). I got the Borla welded in because without it, it sounded a bit tinny in my opinion, and it was way too loud. The cops were hounding me, and my neighbors were complaining.

The car is still loud enough to set off pretty much every car alarm in the parkade at work (which I find funny, but very noisy).

I am curious to see how the M2 duals, or RB catbacks sound however. The loudness is fine with me, but my better half doesn't like it, and it does draw a bit too much attention

thesaint

I used to have the Rb catback before I switched to the n1 dual. The Rb is definately on the quiet side. On a scale to 1 to 10, 1 being the stock and 10 being the apex n1, the rb would be a 2.5. It's that quiet. So quiet that I got bored with it that I did an even swap for someone's apexi.....As far as the M2 is concerned, I do not know how loud it is. I'm sure that it is on the quiet side, because that's Brian's style. I was talking to him and he showed me them before they came out and the piping is 3" straight thru, even thru the muffler. It should flow well.

RX7Elmo 08-25-02 05:46 PM

i'm running the RB duel with n-tech highflow and dp and it's quiet. when you get on it i hear the motor/turbos more than the exhaust note. My setup is quieter than any other exhaust system i've heard even if they have a stock cat. I personally like it that way, then i can 'zoom zoom' up and down the street w/o attention....or sound wise at least.

Danny

Fritz Flynn 08-25-02 07:17 PM

Danny open your window turn down your radio or both. That setup isn't all that quiet and trust me your neighbors know when your coming :)
Glad you like the N-tech and rb. I now have a sr hf and m2 dual and its also very conservative looking and sounding just the way I like it but its still 3x as loud as the stock setup. Prior to the m2 dual I had the apexi n1 single which was light and had nice flow but to much of an attention getter. My wife could hear me coming from 3 miles away :) The apexi n1 silencer cuts boost by a pound so thats some significant restriction. When I switched to the m2 my boost levels have remained about the same so the flow must be decent vs the n1. I believe the best flowing least noise producing combo would be a dp, bonez hf, and rb catback. With this setup you can both hear your radio and your passenger telling you to slow down and you will have happy neighbors.

94touring 08-25-02 07:21 PM

I ran dp, mp, and n1 dual with and without silencers for about a year or more. That setup is just way too loud, even with the silencers in. I'm not sure a highflow cat could help either. I now have the m2 dual, and its perfect. Sounds good and isn't too loud, makes some noise but not enough to draw a ton of attention.

capt. bill1 08-25-02 09:00 PM

I run a DP, a SS MP with a Borla straight thru muffler put in it and a PFS cat back(came with the car). Sounds great and is not too loud.
I had a N-Tech high flow (what a joke) cat. With the N-Tech cat I had 7lb of back pressure. With the Borla, 2lb. Don't waste you money on a "high flow" cat unless the company can give you real world back pressure numbers.

rynberg 08-25-02 10:04 PM


Originally posted by Fritz Flynn
Danny open your window turn down your radio or both. That setup isn't all that quiet and trust me your neighbors know when your coming :)

No kidding. I have Bonez downpipe and RB dual-tip with stock cat and it is quite a bit louder than stock with the windows down. Especially when you let off the gas at about 3k rpm in 2nd or 3rd. With the windows up, it sounds barely louder than stock.

overkill 08-25-02 10:23 PM


Originally posted by 94touring
I ran dp, mp, and n1 dual with and without silencers for about a year or more. That setup is just way too loud, even with the silencers in. I'm not sure a highflow cat could help either. I now have the m2 dual, and its perfect. Sounds good and isn't too loud, makes some noise but not enough to draw a ton of attention.
Thanks for your info. Did having the silencers have ANY effect on sound levels? Do you happen to know if you lost any boost from them while installed??

94touring 08-25-02 11:03 PM


Originally posted by overkill

Thanks for your info. Did having the silencers have ANY effect on sound levels? Do you happen to know if you lost any boost from them while installed??

The silencers did lower the noise, however it was still kinda loud. Not to mention that the silencers robs tons of horsepower. While I don't have dyno numbers showing how much power loss there is, I raced a friend in his modded 300zx with and without them in. We made several passes with the silencers in, and I could barely beat him. With the silencers out I would walk away, easily 4 or 5 lengths. There is just no way I can see anyone running straight exhaust with the n1's on the street with no silencers, their just that loud. The boost stayed fairly stable with the silencers in compared to out, maybe a couple psi lower.
Personally after experimenting with exhaust setups, I would go with either the racing beat or m2 exhaust, with or without the highflow cat depending on how loud you like it. You can always use a midpipe first and switch later if its still too loud, but I seriously doubt that. Plus your not going to lose that much power with those exhaust, they will sound MUCH better, be quieter, and look stock.

RX7Elmo 08-25-02 11:51 PM

Fritz,

i've never run a stock exhaust setup so I wouldn't know man!! But i've sat in many FDs with various exhausts and i'd say my car is much quieter than theirs. I dont' mind being heard though. And um...stereo..oh yeah, i have to turn that down huh??

capt bill1, i'm curioius if you did a backpressure test with the stock cat? Was your n-tech run with the airpump or not?

I wouldn't say the n-tech is a joke from my experience, It's much better than stock.

Danny

youngteggo 08-26-02 12:09 AM

Has anyone tried SR's muffler?

Marc

RecKleSs 08-26-02 10:44 AM

I have a downpipe, midpipe, and A'pexi GT Spec Exhaust. All the cats were removed and I love it. The silencer makes a huge difference in db. It is extremely quiet when I put the silencer on and I only use it when I take out my girl sometimes. She loves it when it's off.

Also, I made 302 RWHP with this setup and a few other little mods. :D

RX7Elmo 08-26-02 11:22 AM


It is extremely quiet when I put the silencer
I'm sorry, but i would have to beg to differ on the above comment. I think you are still considerably over 100db with dp.mp.apex gt exhaust with silencer.

Danny


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