The Definitive MSP Exhaust FAQ

[Striker187]

I prepared this faq to help newbies find answers to common exhaust questions and to provide a basis for helping people decide on an exhaust. Its a little overdue but better late than never right? It was written specifically for my fellow msp owners but I suppose it can be used for turbo proteges as well. For soundclips/vids of various exhaust setups, visit the sister thread. If you have any questions/comments/suggestions, send me a pm and Ill see what I can do.


Table of Contents

1. Basic Terminology
2. Turbo Exhaust Basics
3. Stock Exhaust Info
4. 2.5" or 3" Piping?
5. Stainless Steel or Aluminized Steel?
6. Mandrel Bends or Crush Bends?
7. Mandrel Bend Availability
8. Connection Types
9. Custom Exhausts?
10. Mufflers
11. Flex-Sections
12. Catalytic Converters
13. Resonators and Silencers
14. Exhaust Cut-Outs
15. JDM Styling
16. Cost Issues
17. Other Things to Keep in Mind

- List of Available Exhausts
- Vendors and Additional Websites



#1) Q: Ack, people are tossing around all these terms and I dont know whats what! Help!!!

A: Ok calm down. Its easier than you think. Your stock exhaust comes in 5 sections that are bolted together. Starting directly from the exhaust turbine outlet, the exhaust goes like this:

a) The downpipe comes first. On the msp, the downpipe consists of two sections that are bolted together. The first section has become known as the s-pipe, due to the fact that it's shaped like an "S". This piece bolts directly to the turbo. You can actually see this if you pop your hood. It is a cast piece, most likely cast iron in my opinion, so its brown colored. As soon as it comes off the turbo, the piece makes a 180 and bends back underneath the turbo. I should mention that many people on the forums say downpipe when they really mean the midpipe (which comes later).so be careful and make sure you know what they mean.<O</O

b) The second section of the downpipe has become known as the j-bend. The j-bend bolts directly to the s-pipe and makes a 90 degree bend to run underneath the car. At the end of this piece is a flange with two springs.<O</O

c) The midpipe is next and starts from the spring flange and ends after the second cat. Yes, you have two catalytic converters. This is just a straight section of piping. Take note that several of the midpipes available for purchase include the j-bend section. Some do, not all though.

d) The catback section is next. Aptly named, this section of piping runs from the second cat all the way to the rear axle, though people normally use this term to describe everything from the cat back, including the muffler. In addition, the catback also contains one resonator.

e) The axleback section is last. This section starts at the end of the catback and bends up over the rear axle to finish off the exhaust. The muffler is included in this section.


#2) Q: Great, so whats the best exhaust for my turbo beast?

A: Simple. The best exhaust for a turbo is no exhaust! See, turbos operate off the flow of your exhaust gases. The easier it is for the exhaust gases to go through the turbine and out the back of your car, the faster the turbo will want to spin.that means more power!! When exhaust gases flow through the exhaust piping, they start to slow down due to a number of different things: drag/wall friction, temperature drop, etc. So now the turbo has to work to keep these gases moving. This is the dreaded backpressure at work. Backpressure is the enemy of turbos!!!

Alright so why even have an exhaust? Well for one, the exhaust gases are +1000F. Do you really want that shooting directly into your engine bay? Didnt think so.

Ok so how about I just make the shortest exhaust possible and have it end somewhere underneath the car? Well actually, you can. Its called an exhaust dump and they do work. Some people get fancy with it and have it exit out the sides of the car, like right behind the front wheels or something. But before you run off to your local exhaust shop, consider this. Unless your exhaust dump contains at least one catalytic converter, its not street legal. Personally, I think if you do stick a cat in there, youve defeated the purpose of your exhaust dump. Also, it will be loud. I mean LOUD. Were talking ear-splitting, ground-shaking, window-shattering, hear-ya-coming-from-two-miles-away-and-another-four-after-you-zip-by loud. Be prepared for the extra attention youre bound to attract.you best have something to back it up with.

Well crap, what am I supposed to do? Bigger piping is the answer. Idealistically speaking, the bigger the better on a turbo. If you could stick a 10 exhaust on your car, by all means, go for it. But at some point, youre gonna get to a point where any bigger is just plain useless. Youre simply not flowing enough exhaust to warrant the bigger piping. I mean, its not gonna hurt anything, but it certainly wont help. If anything, your wallets gonna take the hit. 10 piping would be extremely expensive and would look a little ridiculous wouldnt it? Keep in mind, +800 hp supras run at max, 4 piping.

 

[Striker187]

#3) Q: So is my stock exhaust really that crappy?

A: Well, not exactly, but there are substantial improvements to be made. Wait a secnot exactly?? Yeah, Evos have something like 45 mm (thats 1.77 in) diameter stock piping and they make close to 300 hp..hey thats pretty impressive. When I had my catback replaced, I measured the stock piping at several places, including the crushed sections at the bends. Heres what I found. These are inner diameter measurements:

1 11/16 inches - 2 3/8 inches = 1.6875" - 2.375" = 42.8625 mm - 60.325 mm

See, were not that bad off.



#4) Q: Now Im really confused.what exhaust size should I get?

A: Ahhh the endless debate. 2.5 or 3 piping? To be perfectly honest, either one will do just fine. There is a graph in the book, Maximum Boost by Corky Bell, that can be used to estimate the approximate piping size needed for a certain horsepower. If I recall correctly, 2.5 piping will support ~350 whp..its definintely above 300 whp.

So why go 3? Remember how I said that at some point, the idea of putting larger piping on just doesnt make sense because you wont gain anything? 3 is probably right about that limit. You might gain a tiny bit more hp over a 2.5 system but I seriously doubt you will feel much of a difference, if anything. However, and this is just my personal opinion, I feel the 3 system will make a slight difference in the upper rpm band, where your engine is flowing maximum quantities of exhaust gases.

Is that why you went 3? Yeah pretty much. Also, I noticed the difference in my friends turbo civic when he changed from a 2.5 to a 3 exhaust. He was running a similar size turbo to ours. Im positive I would have been just as happy with a 2.5 exhaust though.<O</O

 

[Striker187]

#5) Q: Stainless Steel (SS) and Aluminized Steel (or mild steel)...what's the difference and which should I choose?

A: Ok it's been a little bit since my materials class but if memory serves me right, stainless steel has a higher chromium content than ordinary steel. Aluminized steel has an aluminum content to it. What happens when they rust is the key.

When stainless steel rusts, the rust that forms is stable...I think it's chromium oxide. In effect, the rust forms a barrier that protects the rest of the metal. This is why stainless steel systems will often outlast you, me, and probably some cockroaches too.

When aluminized steel rusts, the aluminum will corrode first. However, once all the aluminum is consumed, the steel begins to rust. The rust formed here is unstable and flakes off easily. Thus, no protective barrier is formed and over time, the whole system can be consumed over extended periods of time.

So which material should I go with? This is going to depend on a few things: where you live, the size of your wallet, and to an extent, how long you plan on keeping the car.

Why does where I live make a difference? If you live down south where it never snows, youve probably never had to deal with salt on the roads. But in places where it snows, salt is spread on the roads to help keep them from icing over. Good for safety, bad for rust. This salt-watery mixture coats the undercarriage of the car, including, you guessed it, the exhaust. Aluminized steel (or mild steel for that matter) will rust through pretty quickly in these conditions. For this reason, if you live where salt is on the roads in the winter, go SS, period. There is also a section of the U.S. known as the Rust Belt. This belt extends from the midwestern states to the northeastern states. The conditions in the air promote corrosion more quickly (I dont know why) so if you live here, go SS. Any place else, aluminized steel will do just fine.

What about the other reasons? SS is more expensive than aluminized steel. I was quoted a $100 difference between an aluminized steel catback and a SS catback. The really nice part about SS though is that you will never have to worry about rust. Which leads into the other reason, how long you will keep the car. I live around the lace>Houston</ST1lace> area so aluminized steel is just fine for me. If you want proof, I put an aluminized steel exhaust (and a s/c for extra kicks and giggles) on my dads 4runner about 5 years ago. There is still very little sign of rust on the piping, save for around the base of the tip where water collects when it rains. You can expect a good aluminized system to last for a good 5-7 years with no problems.

In defense of aluminized systems though, ceramic coatings and/or VHT paints can help extend the life of the system. So if you're iffy about the conditions where you live but don't/can't spend the money for an SS system, this may put your mind more at ease.

Oh FYI, one way to tell the difference between SS and aluminized steel, you can use a magnet. Aluminized steel has magnetic properties and will attract the magnet. Stainless steel does not.

Well what did you do? On my msp, most of my exhaust is SS, just because I didnt want to worry about rust at all.


#6) Q: Mandrel bends or crush/press bends.whats the difference while youre at it?

A: First, lets look at crush bending. This is how most exhausts are made. To bend the piping, they use a machine that forcefully bends the pipe, but at the same time crushes the section that is bent so that there are no crinkles in the piping. In effect, this makes that portion of the piping smaller in diameter. But why? Think of it this way: imagine a circle shaped race track. The shortest distance around the track is closest to the infield right? The farther you go out from the infield, the longer the distance you have to travel around the track. Now imagine taking a straight piece of pipe and bending it to make a 180 degree bend. The inner part of the bend will be shorter in length than the outer part right? So youre effectively crushing (compressing) the inner bend section of piping and stretching the outer bend section of piping because remember, you started with a straight section of piping. You would actually end up with crinkles on the inner part of the bend. You can see this is some older exhaust systems. What this crush bending machine does is make the inner section of piping around the bend longer by decreasing the overall piping diameter, i.e. it crushes the piping uniformly to create a smaller diameter size. This eliminates those nasty bumps but has instead reduced the size of your exhaust at the point, creating a bottleneck in your exhaust flow! The nice thing about it though is that it is fast, cheap, and easy to do so car manufacturers like to use this method to churn out huge quantities of exhausts.

Mandrel bending is way to bend piping, but keep the same diameter around the bends. Im not quite sure how it works but it takes a very expensive machine to do. However, since your exhaust is now all one size, it will flow better.

So youre telling me I should go with mandrel bends? Bingo. While the gains are probably not substantial, there are gains to be had nonetheless. There is a reason why the technique was developed for race cars. Function over form right? Now some people may say that if you get bigger piping, like say 3, and have it crush bent, itll work out to be about the equivalent of a 2.5 system. Honestly, I have no clue nor do I have evidence to refute or deny the claim. However, I will say that exhaust gases like a smooth-flowing exhaust.its youre decision from there.

And you went with mandrel bends right? Definitely.

 

[Striker187]

#7) Q: So where can I find this mandrel bent stuff?

A: Lots of places. I would say 99% of the exhausts that are available on the market use mandrel bends. In fact, every system listed at the end of this faq uses mandrel bends.

Well what if I wanna go custom? Chances are, your local shop will NOT have access to a mandrel bending machine. They are big and expensive and demand is usually not high enough to justify keeping one around. But dont lose hope. Your local shop should be able to order pre-bent mandrel bent sections of piping and piece together the necessary bends to create your exhaust. Its not hard. Any competent place should be able to handle it. My catback was created in this manner. The place fitted a crush bent template exhaust to my car, and then using the template as a guide, cut and pieced together my exhaust.



#8) Q: Slip-fitting and weldingwhats it all about?

A: There are three ways that exhausts are usually joined together: 1) the ends are flanged and bolted together; this how the stock exhaust is put together, 2) welded together, either TIG, MIG, or even SMAW, or 3) slip-fitted and clamped or welded together.

Great so whats a slip-fit? In a slip-fit, one end of an exhaust section is enlarged slightly using something I believe is called a swelling machine. It makes the end section of a pipe slightly larger in diameter, say a 2.5 diameter to a 2.6 diameter, granted those are rough numbers but you get the idea. Then the other exhaust section is simply slid into the other.slip-fit, get it now? The sections are held together by an exhaust clamp or welded together. This type of connection is easy to do and works just fine. The only thing you want to keep in mind is which exhaust section you swell. Lets say youre going to connect the midpipe to the catback with a slip-fit. You want to swell the catback side and slide the midpipe inside of the catback. With this type of connection, exhaust leaks are next to nil.

TIG, MIG, or SMAW? You speaking a foreign language here? Actually, they are three types of welding: Tungsten Inert Gas (TIG), Metal Inert Gas (MIG), and Shielded Metal Arc Welding (SMAW). SMAW, or stick-welding as it is sometimes called, is the most common type of welding done and is the easiest to do. TIG-welding is the most difficult but it produces the strongest weld. MIG-welding is somewhere in between.

So who uses what? Most of the exhaust companies, especially the ones made by the big companies (Greddy, HKS, etc.), will use TIG-welding to connect their pieces. The nice thing about a TIG-welded exhaust is that you dont have to use a slip-fit to get things to fit together; you directly weld one section to the other so you get a cleaner look to your exhaust.not that anyones gonna really see it. In addition, TIG-welding produces the smallest weld in terms of width, which adds to the whole clean look.

Performance shops that make their own exhausts will either use a TIG or MIG-weld. It takes a fair amount of skill to produce a good TIG-weld though. A good TIG-weld will look like a narrow row of equally-spaced, overlapping dimes. The nice part about a TIG-weld is that it is the most penetrating of the three welds so welding sections of the exhaust together directly is not a problem. It is also the strongest of the three welds.

A regular exhaust shop will more than likely use SMAW to weld their stuff together. It is faster, easier, and cheaper to do. But that doesnt mean that SMAW isnt good. It does what its supposed to do quite well. It just doesnt look as pretty as the other welds. Also, since SMAW does not produce a deep, penetrating weld, a slip-fit connection should be used, and then these welded together (rather than clamped) should you choose to go in this direction.

A MIG-weld is somewhere in-between the two and can be used either way. Some performance shops and even some regular exhaust shops will use this method for certain jobs.

So how was yours done? My downpipe/midpipe was made by GHL Motorsports and was TIG-welded. One slip-fit and clamp connects the downpipe to the midpipe. The midpipe is connected by a flange to my catback. My catback is all connected together by slip-fits that were welded together using SMAW.

 

[Striker187]

#9) Q: Do I go buy one or have one custom made?

A: It depends. Pretty much, it comes down to brand preference, specifically, the muffler. If you dont like whats on the market, go custom. All the exhausts follow pretty much the same piping route and are either 2.5 or 3 in size. Once youve decided, heres some advice (this is mainly for those who are going custom). Go to place you trust. Talk to the people. Have them explain to you exactly what theyre going to do. Make sure you know exactly what youre getting and that what youre getting is what you want. Can they do a system with mandrel bends? Is it gonna be a slip-fit or TIG-welded system? What material can they work with? And get a quote before they ever start working on your car. Once last thing about a custom job; I have noticed that with some custom jobs, the muffler tends to slant downward because the shop could not get the right bend over the rear axle. Just be careful of this.

What did you do? I chose to buy a downpipe/midpipe combination made by GHL Motorsports because a custom job would have cost me way more. I chose to go with a custom catback because I wanted to use a 5zigen Fireball muffler that was not offered by anybody as part of a system.



#10) Q: If Im going custom, what muffler should I choose?

A: Whatever muffler youre a fan of. Theyre all gonna flow pretty much the same so youre not gonna gain much/lose much hp if you choose muffler X over muffler Y. Go with what you like and whats in your price range. Also, go visit the sister exhaust thread to get soundclips/vids of a wide range of difference exhaust setups and mufflers. For the love of your msp though, please dont get a flowmaster!!! Especially their Delta series..they flow the worst, in some cases, worse than stock. Try to stay away from e-bay mufflers too (ahem, OBX). Im just not a fan of them.

Awww come on, cant you help me out any more? Ok ok, heres a few mufflers I recommend: 5zigen, Blitz, HKS, APEXi, RS*R, Tanabe, Greddy, JIC-Magic, Skunk2, Veilside, Thermal R&D, Magnaflow, Hayame, Tsudo, AC Revolution, Vibrant. I have not heard a Veilside, RS*R, or Skunk2 muffler myself, but I understand they are good. Personally, I think it would be badass if someone got a Fujitsubo muffler.

The louder mufflers are usually Blitz, Tanabe, Skunk2, and Veilside.
The quieter mufflers are usually 5zigen, HKS, APEXi, with HKS being the quietest.
The rest are somewhere in-between.

The cheaper mufflers are usually Thermal R&D, Magnaflow, Hayame, Tsudo, AC Revolution, and Vibrant. These are usually in the $100-$150 range.
The JDM brands run in the $200-$250 range but can reach upwards of $300 depending on the type of material used.

Whyd you choose 5zigen? I always liked the look and brand though Id never heard one before. The price wasnt bad eithernormally priced around $250. I was also considering HKS, Blitz, and Skunk2, but after some research, I ruled out Blitz and Skunk2 because they would probably be too loud. I knew that HKS was generally pretty quiet and cheaper at about $200. But after some more research and a lucky find, I decided to take a chance with the 5zigen and got it for $217. I am extremely pleased.

I will tell you, the msp has a natural roll/rumble to its exhaust note, almost like a Subaru with its boxer engine. While the roll is not noticeable (depending on the muffler) with the stock midpipe in place, once you do replace it, it will be quite noticeable. Dont believe me? Go watch the before and after videos of my car when I got my downpipe/midpipe.

 

[Striker187]

#11) Q: Whats a flex-section and do I need one?

A: A flex-section is a flexible, braided-steel, section of piping that allows your exhaust to well, flex. See, your engine is connected to the frame by four mounts. Naturally, your engine vibrates and moves about quite a lot, even during normal driving. For comfort reasons, the stock engine mounts are designed with rubber inserts, to absorb and dampen these vibrations. However, this allows the engine to move around considerably.and whatevers attached to the engine will move too, including your exhaust. Remember that spring flange I mentioned way back at the beginning? Mazda engineers put that there to allow for some flex in the exhaust. That way, your exhaust wont crack under the strain of engine movement and help lessen the fatigue caused by smaller movements and vibrations.

So I really need one dont I? Well, its not absolutely imperative that you have one. Your car will not stall/explode/fall to pieces/catch fire without one. However, I highly recommend that you have one in place. The stock engine mounts are relatively weak and the engine moves considerably. If you get/have an exhaust with no flex-section, you should definitely replace the front and rear motor mounts with stiffer ones, though on lightly modified cars, replacing the front one only will be sufficient.

Wheres this flex-section supposed to go? It should be around the same place as the stock spring flange, i.e. just after the j-bend.

And you must have one right? Actually, I dont. While I did want one, my midpipe did not come with one. Instead, I replaced my front motor mount with an AWR A/T (automatic transmission) motor mount. The A/T ones are slightly softer than the M/T ones so engine vibrations are not transferred through the frame (and into the cockpit) as much. I do plan on replacing the rear motor mount in the future.

 

[Striker187]

#12) Q: Cat or no cat?

A: First, lets get something straight. I am not a tree-hugger by any means. However, I do respect the environment. With todays technology, cars can run nearly pollution free with a working catalytic converter in place. Whats more important here, the performance of your car or tomorrows environment? I recommend that you have at least one cat.

But dont you lose a bunch of horsepower? No, not much. You will lose a little, but its not like its gonna be the one thing that causes you to lose a race or something. You might as well take your spare tire out; youll probably get the same results. Oh by the way, your cars gonna smell like sulfur at every stoplight without one.

Whys my check engine light (CEL) on? Well, thats a consequence of removing your cats. For emissions purposes, your cars ECU monitors the oxygen content of your exhaust gases by means of two O<SUB>2</SUB> sensors. The first sensor is located near your turbo; I believe it is tapped into your exhaust manifold actually. The second one, and the one that concerns you, is located downstream, in-between the first and second stock catalytic converters. Its quite easy to see the sensor. It looks like a big black spark-plug shaped thing. What the ECU is looking for is a signal change between the two sensors; its a voltage drop I think. If the first cat malfunctions for whatever reason (or if its missing!!), the signal change disappears and the ECU will flash the CEL. So if you do decide to get a cat, be sure the O<SUB>2</SUB> sensor is placed AFTER the cat. And FYI, Ive heard from several people that their gas mileage sucks when this is the problem the ECU is detecting.

I still dont want a cat but I dont want to be staring at a CEL. Isnt there something I can do?Theres a couple of fixes. One is called a MIL eliminator. Its available from Apex Motorsports (website address is at the bottom) and its cheap. Im not entirely sure how it works but it somehow alters the signal going to the ECU and tricks it into thinking everything is ok. The only downside is that it must be hard-wired into the O<SUB>2</SUB> sensor wiring so if youre skittish about cutting/splicing wires, this might not be for you.

There is another option, but I have not followed the thread completely so I do not know if it is a long-term fix or not. The thread is here. It uses a modified spark plug non-fouler to move the O<SUB>2</SUB> sensor farther out of the exhaust stream. The idea here is to lessen the amount of oxygen the sensor is able to detect and tricks the ECU into thinking everythings ok. This method does not require wire-cutting so its a bit more of a plug-and-play type deal. And its cheap as well.

You could always just unplug the CEL too, though thats kinda stupid if you ask me. How are you supposed to know if anything else is wrong?

Can you recommend a good hi-flow catalytic converter? Random Technologies catalytic converters are arguably the best though they are pricey.about $150 or more. Magnaflow, Carsound, and Catco are other brands that many people choose to go with. They are cheap and get the job done. Expect to pay about $100.

Lemme guess, you have a catalytic converter dont you? Of course. And even with it, my car still smells like ass after a hard run. But I dont have a CEL. I dont know what brand it is though....whatever brand GHL uses.


#13) Q: Whats a resonator do and do I need one?

A: A resonator is basically a pre-muffler. In fact, some smaller mufflers are used as a resonator. It is placed upstream of the actual muffler. On the stock exhaust, it is located just after the cats; its the big bulge looking thing. A resonator is used to quiet a loud exhaust, reduce droning at highway speeds, and reduce raspiness/buzziness in an exhaust note.

So how do I know if I will need one? Honestly, you probably wont know. You can use the soundclips/vids in the other thread to get a rough idea plus the general guidelines above to take an educated guess. My advice is to go without one first and see if you need it or not. If you end up wanting one, its not hard to have one installed. A Magnaflow resonator will cost about $70 or so.

Can I use a silencer instead? Yes, but not all mufflers can accept one. Also, since a silencer is basically a big restriction in your muffler, you will lose some power. The exhaust note usually ends up sounding not too good either. Ive heard of cheaper ones actually popping out due to all the pressure. In short, I wouldnt recommend it. A resonator would be much better and you wont lose power either.

 

[Striker187]

#14) Q: Screw all this quiet stuff, I want the loudest mother-$%&#(! on the road...what can I do?

A: An exhaust cut-out is what you're looking for. I had mentioned this earlier (remember the part about an exhaust dump?) but here's a more in-depth look into it.

This is how it is normally set up on a car. Just before the catalytic converter(s), a Y-pipe is installed. It's simply a piece of pipe that branches off in two directions and it's in the shape of a "Y". One branch connects to the rest of the exhaust. The other, however, is attached to nothing. It just ends under the car and is simply capped off by a removeable plate.

Under normal driving, the plate is left on and exhaust gases flow normally through the entire system. But when you want extra power, like at a track, the plate is removed. Now, your exhaust is effectively twice as short!! And remember, generally speaking, less piping equals more power!!!!!

Here's a couple things to keep in mind. As stated before, it will be loud. LOUD! REALLY LOUD!! You will effectively be running no muffler and/or resonator, and no cats (which is illegal). It'll sound like you have a big block V8. It's quite intimidating. So expect lots of attention....and you best be ready to back it all up. The nice thing about it though is that it's cheap. About $50 for the Y-pipe.

One other thing, it can be a hassle to crawl underneath your car every time you want to remove/reattach the plate. One alternative is the electric cut-out. It uses an electric motor to mechanically open/close the plate. The motor is connected to a switch that is installed inside the cockpit. One flip of a switch is all it takes to go from street to strip. Probably the most popular one is made by QuickTime Performance, www.quicktimeperformance.com.



#15) Q: I want that "JDM" look where the muffler is angled, can I do that?

A: Yes, you can. Apex Motorsports's catback sets the muffler at an angle upwards; I am not certain about the side angle but I believe it is set at an angle as well. I am unsure if JIC-Magic's catback is angled or not; I believe it is angled similar to Apex's. Your other option is to have it custom-made. This look though is purely for aesthetic reasons.

FYI, there is a valid reason why this whole slanted exit started. Tuners figured out that they could eliminate a couple bends by have the exhaust exit at an angle rather than exiting straight. Less bends equals less restriction equals more power. It caught on from there. I believe Apex Motorsports's catback is the only valid use of this as it goes under the rear axle rather than over, eliminating that crazy bend over the axle.



#16) Q: So all in all, how much is this gonna cost me?

A: It all depends on where you go. Search the internet, search the phonebook. You never know what kind of deals you might turn up or what kind of crazy shop you might find thatll give you a good price. At the end of this faq are several websites that I have visited in an attempt to find the lowest price, though these were mainly for mufflers only because I chose to go custom. But to replace your ENTIRE exhaust, expect to spend around $1000, plus or minus a couple hundred. By the way, exact prices for the exhausts listed at the end of this faq are not shown because there are too many discrepancies depending on where you buy from. Come on, I cant do ALL the work for you.

HOLY @#$%!! I dont have the money to do it all at once, what part should I replace first? Based on dyno results, and my personal experience, the midpipe will yield the biggest gains, probably around 10-12 hp. These are usually about $300-$400 depending on size, material, coating, and the inclusion/exclusion of a hi-flow cat.

The catback alone will probably not yield a substantial increase in power. I replaced my catback first and I honestly didnt feel much of a difference. Id say expect maybe a 2-5 hp gain. However, when paired with the midpipe, Im sure youll realize higher gains. Expect to pay around $500-$600 for a quality catback, including the muffler.

As for the downpipe, Im not sure what kind of gains are to be had, though you will definitely gain hp. How much, I cannot say. But since youre replacing the rest of your exhaust, why not? Might as well free it all up right? These are around $300-$400.

People always tell me custom is cheaper. Is it true? It entirely depends on where you go. Performance shops will usually charge about the same as, if not more, than commercially available systems because it is a one-off system they will be doing. Remember the law of supply and demand? However, performance shops will usually do a quality job. But at the same time, you might find a place thats dirt cheap that does decent work. You never know. Good rule of thumb though, you usually get what you pay for. Remember, cutting corners normally doesnt cut it. Youll have to shop around and find your own answer to this one.

 

[Striker187]

#17) Q: I think Im all set. Anything else I should know about?

A: Heres a couple more things to keep in mind.

Keep the piping size consistent. If youre piecing together an exhaust, you might run into this problem. If you cant/dont want to keep the same size throughout, always go small to big, never the other way around.

Keep the material type consistent. While it's not a huge concern for a system that will be bolted together, if your system is to be welded, this is a definite plus. Welding mild steel together with stainless steel isn't the best idea in terms of strength of the weld, but it can be done. If you absolutely must combine materials, have them bolted or clamped together.

Expect some rattles here and there. Remember, the undercarriage of the car was designed with the stock exhaust in mind. Clearances will be much tighter with larger piping. My exhaust tends to rattle against the underside when I drive on bumpy roads. Its worse when I have passengers in the back seat. It also rubs slightly against the rear subframe. I dont worry about it though.

Replace the stock exhaust hanger bushings if you can. The stock ones are made of a soft rubber and allow for way too much movement. Replace them with Kartboy exhaust hanger bushings. Theyre much stiffer and will keep the exhaust from moving about too much.

Ceramic coatings are beneficial but not necessary. They help keep heat inside the piping which keeps the exhaust gas velocity up (as the gases cool, they slow down). They can also keep excess heat from leaking into the engine bay. If you have the money, its a nice touch to have. Check with the vendors to see if they offer this or not.

Order an extra set of turbo studs when replacing the stock s-pipe. The stock studs (there are five) use compressed nuts that tend to strip the threads when you remove them. You're guaranteed to strip at least one...more than likely more than one. You can purchase replacements which will use lock washers instead from Squatty's Shop, link is listed below.

 

[Striker187]

(reserved)

 

[Striker187]

(reserved)

 

[Striker187]

(reserved)

 

[Striker187]

List of Available Exhausts for the MSP

<O</O
Catback:

Apex Motorsports: 2.5" or 3" mild steel
<A href="http://www.apexr1.com/" target=_blank>Essential Speed: 3 SS
Greddy: 60 mm SS
JIC-Magic: 60 mm SS
Magnaflow: 2.25" SS<A href="http://www.magnaflow.com/">
Thermal R&D: 3 SS

J-Bend-back:

Corksport: 2.4 SS
Perrin Performance: 3" SS

S-pipe-back:

Corksport: 2.4" SS (offered by www.horsepowerfreaks.com)
Essential Speed: 3 SS
ETD Racing (Vibrant Exhaust): 3 SS

Midpipe (includes j-bend):

Apex Motorsports: 2.5 or 3" mild steel
Essential Speed: 2.5 or 3 SS

Midpipe (excludes j-bend):

Mental Addiction Motorsports: 2.5 mild steel or SS

J-Bend only:

Mental Addiction Motorsports: 2.5" mild steel or SS

S-pipe only:

Corksport: 2.5 SS
Mental Addiction Motorsports: 2.5 mild steel or SS

Downpipe only (S/J-pipe combo):

GHL Motorsports: 3 SS, option to include midpipe
Mental Addiction Motorsports: 2.5" mild steel or SS

Full exhaust:
<O</O
GHL Motorsports: 3 SS


Old exhausts you may run across for sale/e-bay/etc.:

Spool 2.5" SS catback (no longer available)
Protosport 2.5" midpipe (no longer available)
Ion Performance 3" full exhaust (potential scammer??)
Magnus Motorsports 3" downpipe-back (no longer available)

 

[Striker187]

Buy stuff from here:
<O</O

Forum Supporters:

<A href="http://www.apexr1.com/" target=_blank>Apex Motorsports
Anthony Woodford Racing (AWR)
Corksport
Crossover Auto
Essential Speed
ETD Racing
GHL Motorsports
<A HREF="http://www.hiboost.com">HiBoost</A>
Horsepower Freaks
Kartboy
Perrin Performance
Protege Garage
Mental Addiction Motorsports
Squatty's Shop (Street Unit)

Personal sites I have visited:
<O</O
www.adventon.com
www.ardperformance.com
www.finalstageauto.com
www.groupbuycenter.com
www.hopupracing.com
www.inlinefour.com
www.lightningmotorsports.com
www.optauto.com
www.rpmmotoring.com
www.wholesalehyperformance.com

 

[orng1]

Great thread, good work. should be a sticky in my opinion.

 

[Rawyzf]

Nice thread, you might want to use this as a reference.

 

[Tito1]

This thread is sweet...great job.


I have one ???? What is the ID of the the stock MSP muffler? Does it swell to a larger size or stay under 2.3"?? THanks

 

[jurgs01]

You have definately taken on organizing the multiple exhaust options into a great read for new users. I didn't see a link to your sound clip thread though. Good job!

 

[CasopoliS]

Wow nice writeup. You have some time on your hands! STICKY!

 

[Titanium-99]

subscribing