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Old 05-16-2005 | 03:40 PM
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Default Exhaust advice

I've spent a few hours looking through old threads about X-pipes, RMBs and cats, and I'm confused about what I really want and what's possible.

I currently have a completely stock 86.5. I want a little more volume, but not a lot. I want it to still sound civilized, but a bit more sporty. I also would really like a boost in HP. Sound-wise, it needs to be a car that a date would be comfortable riding in.

From what I've read, I gather that a combo of X-pipe, high-flow cats and RMB would give me a significant power increase, but would be way too loud.

If I keep everything stock and just go with the RMB, I gather that sound-wise it will probably meet my needs but with little or no HP gain.

I also understand that the X-pipe alone gives the sound a little more raspy character, and maybe a little more volume. It also would result in a noticeable power gain.

No matter what I do, I want to keep the stock cats for emissions. Can I put in an x-pipe and use the stock cats? Would it be worth it to do so? Are the stock cats very restrictive?

Ideally, I'd like the x-pipe for the HP gain, plus the RMB for the sound. But would that combo be too loud?

What I DON'T WANT is an American muscle car sound. I want it to sound like an expensive European car (whatever that is). So, what do you think? All opinions welcome.
Old 05-16-2005 | 03:59 PM
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If you don't want American muscle sound then just go for the RMB - sounds perfect for your needs. And a lot cheaper than X pipes and high flow cats (which, unlike RMB will give you real power gains). Not sure about the power lift with X-pipe, RMB and standard cats - it will be noisy though.
Old 05-17-2005 | 08:52 PM
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Thanks. I'm sorta leaning to the RMB by itself. It's pretty cheap so maybe I'll just do that first and see how it turns out.
Old 05-17-2005 | 08:56 PM
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If what you really want is a boost in HP then an X Pipe is what you want. Depending on the set up it won't be much louder than an RMB.
Old 05-17-2005 | 09:08 PM
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X-pipe much loader than RMB. Have one of each on both of my cars and judging from your post you will want a RMB and a set of aftermarket chips. This is what I currently have on my 5sp. and it has nice performance and a throaty voice that is seductive.
Old 05-17-2005 | 09:44 PM
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You should hear a couple of systems before deciding. Once again, depending on the system (with/without cats, with/without RMB) the X Pipe isn't overly loud and adds HP. The RMB is volume only.
Chips will helpt HP with either system.
I prefer a supercharger over chips
Old 05-17-2005 | 10:06 PM
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If you can't listen to other systems first, then start slow with yours.

First, buy an x-pipe for the power increase.
The RMB does nothing for horsepower.

Install the x-pipe, and install the dual cats, and leave the rest alone.
The X-pipe alone will give it more of an "exotic" sound from stock.
The new cats may also be a little louder, and change the tone.
So maybe that is all you will need.

If you find it's still too quiet, I would try replacing the
stock rear muffler with a glasspack or other resonator.
If you bypass it completly, with an RMB, it's going to
be a lot louder...
Old 05-17-2005 | 11:12 PM
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Ive got the RMB, not too loud sounds very good, I wish I could let you hear it before you cut your exhaust up, maybe you could call me and you can hear it over the phone?
Old 05-17-2005 | 11:33 PM
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Isn't the x-pipe a bolt-on replacement? Whatever I do I want to make sure I can return the whole thing to stock without much fuss if necessary.
Old 05-18-2005 | 12:00 AM
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In my experience, chips actually make a subtle change to the sound of the engine.

RMB allows you to actually hear the engine.

I agree that RMB may be the right start due to low investment, simplicity, and the needs you conveyed. Computers can easily be swapped with a buddy to try out the impact of chips before buying. I have had both for many years and like em just fine, but am ready for another progression: X or headers.

An idea for dating and non dating mode. In my car, and probably yours too, there is a big plastic foam-backed cover that goes over the spare tire and under the back carpet. If you remove it, you can hear your RMB better without having to roll down the windows. Put it back in to quiet things down a bit for your date.

RMB + Chips make for a nice sound an power improvement with non-destructive, quick and easy installation. Both are stocked on the shelves of a couple of our favorite vendors.

Not sure where you would get an X from right now.

Last edited by James-man; 05-18-2005 at 09:29 AM.
Old 05-18-2005 | 12:05 AM
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I had thought that the X pipe was only a bolt on replacement of the cats. There is nowhere else to bolt and unbolt, isn't there?

It would be my objective to get aftermarket cats (much shorter than stock), welded to an X and the Cat/X Pair would be a bolt-on replacement for the stock cats.

This is what I want someone to sell to me.
Old 05-18-2005 | 12:51 AM
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Yes.

Originally Posted by 911Dave
Isn't the x-pipe a bolt-on replacement? .
Old 05-18-2005 | 01:22 AM
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I agree with bcdavis. Get the x-pipe with random tech cats. If it isn't loud enough, get an RMB too.
Old 05-18-2005 | 02:14 AM
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Headers...
A little pricey at almost $600.00 for the 78' - 84' MY.
I'm not sure that MSDS even makes a set for yours.(anyone?) Generally a 15-20 HP increase.
The 2 1/2" pipe is a good choice for a free flowing exhaust, slap on some high flow Cats at about $50. -$70.00 per unit and the flat, 15" or 18" Flowmaster muffler.
This will sound like NASCAR and you will offend most everyone outside the motorhead crowd and attract all sorts of law enforcement types. However, if you add a cylindrical, Trush pipe -resonator- on each pipe you will enjoy the sound yet not offend anyone but the elderly, and Mom's with newborns.
This system is without the headers. And HP gains may only be seat of the pants.
Old 05-18-2005 | 02:56 AM
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Originally Posted by mspiegle
I agree with bcdavis. Get the x-pipe with random tech cats. If it isn't loud enough, get an RMB too.
The Random Tech cats are kinda spendy aren't they? Would Magnaflows be just as good?

Michael, wasn't it your car that I recently saw crash pictures of? Too bad. Mine is Prussian Blue also, w/ side molding delete. Here's a pic.
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