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SLP High Flow Catalytic Converter Kit (96-10 All)

Market Price $199.95 You Save 23% ($46.39)
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$153.56

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  • Item 23034
  • MPN# M31040

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Features, Video & Details

  • Improved Exhaust Flow
  • Universal 2.5" OD and ID Design
  • Stainless Steel Construction
  • Ceramic Substrate Material
  • Will Pass Most Emissions Tests
  • Durable Construction
  • Sold as a Set of Two

Review & Installation Video

Review & Install Video

Hey, guys. Stephanie with www.americanmuscle.com, here with the review of the SLP High-Flow Catalytic Converter Kit, from 1996 to 2010 Mustangs. In this video, we're gonna talk about the materials and construction of these cats, and the install as well. I'll talk more about the install shortly, but I can tell you right now, that I'm gonna call this a two out of three wrenches in the difficulty meter because you will need to make modifications to get these installed. You should check out the SLP High-Flow Cats if you're looking for a two-and-a-half inch stainless steel Cat for a naturally aspirated setup because you're trying to abide by emissions laws. But you still wanna ditch the very restrictive factory cats, for something that's gonna open up volume, and a little bit more power from the exhaust. These high flow cats offer a good compromise between staying legal, and still having a great sounding Mustang. You also might wanna check these out if you have an off-road setup on your car currently, but you're looking to tone down the volume or the rasp a little bit. This SLP kit has two Universal, two-and-a-half inch cats that are stainless steel, with an internal ceramic substrate material. This makes these cats perfect for naturally aspirated builds. If you don't have a naturally aspirated setup, I would recommend checking out some of the other options since there is a set of cats with a metallic substrate material, for the force induction carbs. SLP claims that these will pass most emissions tests, but what I would say is that I never promise all high flow cats pass all state emissions tests. That's honestly just the name of the game, and I can't really guarantee something like that, unfortunately. I will say, though, that if you don't feel like swapping out your exhaust when you have your emissions and inspection, then there's no reason not to try these. When it comes to price, you can expect to pay just under $200 for this kit. It's the least expensive option on the site, although the pipes offered for NA cars is only about $25 more. When you're shopping for cats for force induction carbs, the things get a little bit more expensive, because you need a different material inside of the cat to handle a higher exhaust temp for those builds. When it comes to the install, depending on how you install these, you can expect to spend a few hours, and it's gonna be a two out of three wrenches in the difficulty meter because you will need to make some modifications in order to get these installed. What exactly you need to modify will change depending on if you're cutting out old cats and replacing them with these, or if you're adding these to an off-road system. But either way, it's not a terribly difficult install. You're gonna need a good socket set. Something to cut the exhaust with like a Sawzall with a fresh blade, and a jack and jack stands or a lift to get the car in the air. If you're replacing cats with these, you'll already have your location marked for you, and you can proceed. If you're putting these into an off-road system, you need to mark and cut the mid-pipe to make room for the cats. I would then file the pipe down to make it smooth after cutting. The cats do have a specific inlet and outlet side, so you wanna make sure that you have the orientation correct before installing. And you can clamp these into place or weld them in. It's up to you. Wrapping things up here with the SLP High-Flow Catalytic Converter Kit, this is a kit that offers two Universal, two-and-a-half inches stainless steel High-Flow cats, for naturally aspirated applications. These are gonna help you keep your Mustang loud, or help you tone down an off-road setup, and you can check them out more online right here, at www.americanmuscle.com.

High Flow. Are you looking to free up your restrictive exhaust, but are required to use Catalytic Converters? AmericanMuscle has the answer in the form of SLP's High Flow Ceramic Catalytic Converter Kit.

Durable Construction. These SLP Catalytic Converters are made out of Stainless Steel and a durable Ceramic substrate material making them perfect for naturally aspirated applications.

Will pass most emission tests. SLP's High Flow Ceramic Catalytic Converters will pass most states emissions testing procedures. However, check your local and state ordinances for installation and usage regulations.

Application. This SLP High Flow Catalytic Converter Kit is designed for use with Mustangs from 1996-2010 and is sold as a set of two.

Fitment: 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Details

What's in the Box
  • (2) Catalytic Converters
Installation Info
Tech Specs
Will it fit my Mustang?
  • Bullitt - 01, 08, 09
  • Mach 1 - 03, 04
  • V6 - 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10
  • Cobra - 96, 97, 98, 99, 01, 03, 04
  • GT - 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10
  • GT500 - 07, 08, 09, 10

People Who Bought This Item Also Bought

Most Helpful Reviews

4/5
SLP high flows

Overall great product with great customer support. AM price matched it for me and everything. I ended up writing an install guide for the cats in hopes to make the installation for others a bit easier. ...

Read More
Helpful (27)

5/5
SLP High Flow Cats

I had these cats welded on to my bbk o/r x pipe and no complaints at all. Top notch SLP quality, makes a non-catted x pipe sound so much better throughout the rpm band, no more rasp with my exhaust and ...

Read More
Helpful (11)

Overall Rating 4.5 out of 5 stars
Read All 43 Reviews

Customer Photos (4) Submit Your Photo

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26 Questions / 5 Answers

Ask a Question

Hello, I was just wondering if these catalytic coverters will be a direct fit for my 2006 Ford Mustang V6. Also, I wanted to know if they’re California smog legal. Please advise. If they’re not, please advise me on which ones are. Im in need of two. Thank you.

GuMbY

  • Hello, Yes the SLP High Flow Catalytic Converter Kit is a direct fit for the mustang V6 from (96-10), How ever California does not like the high-flow catalytic converters, and unfortunately all the catalytic converters we have are high-flow.

    SpencerM

Helpful (0)

Which is the correct way to install this cat with out putting the wrong way

FredM

  • The inlet on the SLP High Flow Catalytic Converter Kit will be the side where the piping has the small cuts to allow stretching, the outlet will be the smooth tubing section.

    Rob D

Helpful (0)

I have the SLP catted x-pipes (item: 23008, MPN# M31032) the catts were damaged. Will these be a direct replacement?

Al

  • The SLP High Flow Catalytic Converter Kit is designed for use with SLP X-pipes, so these should work as replacements of your SLP catted x-pipes.

    TerriB

Helpful (0)

I have a 03 3.8l and right now I'm true duelled with no cats and pypes m80s but as I idle down my exhaust sputters. I went back to the shop and then tell me it's because of lack of back pressure. I've never heard this noise on a mustang before but anyways I'm wondering if these cats will bring up my back pressure enough to fix the sound. I know it's hard to say without hearing the car but I really don't want to spend another $300 for a quieter car that still sputters.. Any info would be appreciated. Thank you

thrashed

I have an 05 gt stock exhaust my car. Converter died... Will this directly fit or will there be a need for customizing? Secondly I intend to do some upgrades before end of year... All new exhaust new cams intake throttle body.. Will this work with these upgrades or would a different cat work better?

travisc

  • Hello! These are designed to be a direct fit for SLP X-pipes only. You will likely need to do some cutting and/or welding to install them. These will work with the upgrades you intend, although a new exhaust may replace these catalytic converters.

    VincentV

Helpful (0)

Will these fit any 2.5" H-pipe regardless of year? I want to make my catless 2016 legal.

Devin

  • Hello! You may be able to get these to mount up on a 2016 Mustang but it would likely require cutting and/or welding of the existing exhaust..

    VincentV

Helpful (0)

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Customer Reviews (43) Write a Review

Overall Rating 4.5

out of 5 stars

Installation Time:Afternoon

Installation Cost:$100-$250

  • Performance Gain 4.137931 4.1
  • Fit 4.310345 4.3



  • 4/5

    January 11, 2010

    SLP high flows

    Overall great product with great customer support. AM price matched it for me and everything. I ended up writing an install guide for the cats in hopes to make the installation for others a bit easier. Only reason why I gave it 4 stars is because no installation hardware came with the kit. You either need to have them welded in or you need to purchase 4 exhaust clamps. (I bought 4 for $8)

    Andy M.

    Helpful (27)

  • 5/5

    March 31, 2011

    SLP High Flow Cats

    I had these cats welded on to my bbk o/r x pipe and no complaints at all. Top notch SLP quality, makes a non-catted x pipe sound so much better throughout the rpm band, no more rasp with my exhaust and sounds much cleaner

    Mark

    Year: 2002 Submodel: GT

    Helpful (11)

  • 5/5

    December 29, 2010

    great cats

    I am extremely happy with these high flow cats. I was concerned will losing clearance under my 2008 Mustang, but the size of these cats matched the stock cats. This allowed them to be installed right where they are from the factory. Even though they are not large enough to place the O2 sensors, they can still be mounted just behind them on the pipe. Now I have that high performance, that great sound, and maintain my states requirements, exactly what I was looking for.

    Garry Tossing

    Year: 2008

    Helpful (10)

  • 5/5

    March 31, 2011

    dam good

    this product kills the competition. sounds insane while giving the power of straight pipes

    cody

    Year: 2000 Submodel: GT

    Helpful (7)

  • 5/5

    July 28, 2011

    SLP cats

    This things are everything you would expect from SLP. I have them custom welded into a bbk x-pipe with loudmouths and I couldnt be happier with it. they give me the sound and the quality i was looking for

    Dalton

    Year: 2001 Submodel: GT

    Helpful (4)

  • 5/5

    June 30, 2011

    SLP High flow Cats

    I love these cats, they go great with my slp lm1 setup, my exhaust is still as loud as I want, and they fit great too. Would recommend these to anyone who needs Catalytic converters.

    Brandon

    Year: 2003 Submodel: GT

    Helpful (4)

  • 5/5

    April 06, 2011

    SLP Cats

    I added them into my bbk o/r x pipe (long tube headers, Flowmaster 40s) They sound great. Here is the problem My stang has the lowering springs. The drivers side cat has to sit about a inch and a half lower for the tranny linkage than the passenger side This puts them less than 1 1/2 inches off the road. and have scraped them on the road a couple times now. I don't even dare go over a speed bump. I really wish i could keep them they do sound great and I'm not setting off car alarms in the parking lots anymore I am going with the MagnaFlow HiFlow Cats they are a lot smaller in diameter

    Sean

    Year: 1999 Submodel: GT

    Helpful (4)

  • 1/5

    Installation Time: Shop Install

    Installation Cost: $100-$250

    August 19, 2017

    These are garbage

    I bought the all xpipe that these came with, and they turned out to be bad from the factory. Fast forward a few months, and I bought these cats again to replace the old ones. After having them on for 9 days, one has already blown out. I had them professionally installed both times. I will not be buying anything made by SLP anymore. Absolute garbage.

    Anthony12

    Year: 2007 Submodel: GT

    Helpful (2)

  • 1/5

    Installation Time: Afternoon

    October 26, 2016

    Good while they last

    I had bought these for more air flow and better sound. After having them on the car for the last 6 months they've already "clogged" and having problems. I don't use any octane boosters and the car has not had an issue with running rich so I was surprised. I had been told that SLP offers a lifetime warranty on exhaust parts, BUT after contacting them I was rudely told that something must be wrong with my car and that I'm to blame. AND they then stated that cats are not covered under warranty because "no company would do that". I'm extremely disappointed in this product and I'd highly advise going with a different company. For the price, these cats are not worth the head ache they give in the long term.

    MINA

    Year: 2003 Submodel: GT

    Helpful (2)

  • 4/5

    July 31, 2016

    Great purchase, be cautious!!

    Let me start by saying these things sound great! Definetly added a little roar to my 3.8. Not to mention, a little power boost is noticed. On the other hand, my engine light popped on and I definetly noticed a reduction in gas mileage. Be Cautious!

    02Stang

    Year: 2002 Submodel: V6

    Helpful (2)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: $100-$250

    May 22, 2013

    very nice size can fit in a really tight area.

    overall it has stopped the cel from flickering on and off once in awhile. legal for myu area.

    99snake

    Year: 1999 Submodel: Cobra

    Helpful (2)

  • 5/5

    Installation Time: Less than 1 Hour

    March 13, 2012

    SLP Cats

    I have a MAC Catted H-pipe. Found out 2 weeks ago that one of my cats went bad that came with the MAC H-pipe. ordered these SLP cats to Replace the old cats and I have no complaints! (yet i Guess...lol) I had the old cats cut out and the new SLP Hi-Flow cats welded in. The sound is still agrressive and Im sure they perform just as well..if not better.. NOTE: SLP says that these cats are made ONLY for fitment with SLP X-pipes. This is not the case..you can pretty much have them welded in in any set up...

    SyNdicateZ

    Year: 2002 Submodel: GT Mass

    Helpful (2)

  • 5/5

    June 03, 2011

    SLP highflow cats

    great sound and i no longer have SIX cats robbing my horse power

    Bert

    Year: 1996 Submodel: GT

    Helpful (2)

  • 5/5

    Installation Time: Less than 1 Hour

    October 02, 2017

    SLP

    I had an off road x pipe and I was tired of the smell of gas. These cats eliminated the gasoline smell and let me pass emissions. The car still sounds great. Its loud but not too loud. I would highly recommend this product to those who want to run cats on their Mustang.

    CharlesW

    Year: 2003 Submodel: Mach 1

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    July 16, 2017

    great item

    fairly cheap and easy to install, personally i wouldn't have put them on the car but needed them to pass state safety/emission inspections. they do a great job though!

    RichardF

    Year: 2004 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Shop Install

    Installation Cost: $100-$250

    June 23, 2017

    Best cats on the market!

    just bought these for my Mach 1 to pass emissions. They also got rid of the horrible rasp in the exhaust. Great product from slp, and fast delivery thanks to American Muscle.

    JockJ

    Year: 2003 Submodel: Mach 1

    Helpful (1)

  • 5/5

    Installation Time: Less than 1 Hour

    April 26, 2017

    Excellent Choice!!!

    I upgraded my catalytic converter with an SLP Catalytic Converter! It was an excellent choice because it matches my SLP Loudmouth exhaust and the increase airflow is amazing. It also added a great sound to my SLP Loudmouth exhaust. It helps the Cobra draw more attention on the road. People tell me they can hear the Cobra before the even see it!!!

    QuintonT

    Year: 1998 Submodel: Cobra

    Helpful (1)

  • 4/5

    Installation Time: Afternoon

    October 18, 2016

    works great relatively east to install.

    Recommend welding them in. The C clamps that come with the cats are barley Aquitaine .

    Mike

    Year: 2002 Submodel: GT

    Helpful (1)

  • 5/5

    Installation Time: Less than 1 Hour

    March 04, 2016

    Slolz high flow

    Delivered on time and neatly packaged... I was looking for something that wouldn't make my car sound so low and these definitely did the job.. if anything they make my car sound so much better.. definitely recommend if you're looking to keep your car sounding loud..

    Ally

    Year: 2003 Submodel: V6

    Helpful (1)

  • 5/5

    Installation Time: Afternoon

    May 15, 2015

    Kenny

    Great sound, and easy to install with no Eng. Light

    kennyg

    Year: 2008 Submodel: GT Pueblo CO

    Helpful (1)

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