(approx) 4 Hours
Light to Moderate mechanical skill required.
$229.68 (pair)FREE Shipping
Hey I’m Justin with AmericanMuscle.com, and I’m going to be reviewing Pypes high flow cat system for all 1986-2010 Mustangs. These cats are going to be a great compromise for those of you who are required by law to run some sort of catalytic converter system yet still allow you to ditch those ultra restrictive factory cats for something that’s going to flow a lot better, making for more power and sound versus your stock cats. These are going to also be great for someone who might currently be running an offroad X or H pipe, and just wants to tone down that rasp a little bit. This system from Pypes features durable 409 polished stainless steel construction and a very small footprint. This is going to be great for those of you going with a custom exhaust setup, or those of you who might be lowered an inch or two, and won’t have to worry about scraping these over speed bumps. A very important thing to point out with this particular system is that it features a ceramic substrate material on the inside. This system should only be used if you’re naturally aspirated, if you’re forced induction, then you’ll definitely want to check out Pypes’ other system, which features a metallic substrate on the inside, which is far more suitable to handle those higher exhaust gas temperatures. Getting the cats installed should only take you about 2 hours using these two supplied clamps. However, depending on your exhaust setup, you might need to go to your local parts store, and just pick up a couple more clamps. So if you’d like to go to an off road X or H pipe but your local laws just won’t allow for it, or you just want to get rid of some of that excessive rasp with your aftermarket exhaust, without hurting your power, you’ll definitely want to check out a set of these affordable high flow cats from Pypes Performance.
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Features, Description, Reviews, Q&A, Specs & Installation
Fitment: 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Details
CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
March 19, 2020
I installed these cats on an off-road x pipe to pass emissions and no problems 1 year later. Easy install.Helpful (2)
November 16, 2019
Nice addition to my kit
I replaced my entire exhaust and added these to replace my old cats. They look great and go well with the headers and cat back kit. I have not had a chance to get it up on the highway and open it up but I would recommend these to go with your upgrades.Helpful (0)
October 10, 2019
American muscle has great products. Seems to be most of the products are bought from other places. I bought a roush exhaust system for my car along with a pair of catalytic converters for my car. Due to the cats not having a custom tune, they burned out. I wasn't aware that they needed a custom tune. If I had known that, I would have spent the 400$ and bought the bama tuner. They will not honor the warranty. So? Now I have to spend more money to replace them and have them reinstalled.Helpful (5)
October 03, 2019
worked for about 2 years
at first they are great and make the exhaust sound louder. but after about two years they will go out and you will throw a code. They supposedly have lifetime warranty but when I called pypes they would not honor the warranty because I never tuned the computer. Which is none-sense because they advertise these as not requiring a tune. Also, they very likely will not pass exhaust inspection, unless you live in a place where they dont really check emissions. Don't buy these to replace OEM cats unless: 1. you want to pay for the computer tune 2. you don't mind paying the custom welding work required to install (not plug and play) 3. you live in a state with lax emissions checksHelpful (1)
July 09, 2019
Ease of installation was a plus. The car is a little quieter and the drone is almost gone. I would recomend this to anyone looking to upgrade thier cats.Helpful (0)
July 09, 2019
These were for my son's car. He got the desired rumble he wanted from them. I would have given 5 stars and maybe should have. The only issue has been getting the O2 sensors to work correctly since the Cats were installed, but that is probably a coincidence and only an issue with the one or more of the sensors.Helpful (1)
June 11, 2019
Had them installed at a local shop for $130. Looks good, but dont feel a power gain or lose. would recommend! did this because i put a h-pipe on and could not take the smell of gas. this took care of the problem and i enjoy driving my Cobra again.Helpful (0)
May 25, 2019
These cats look great out of the box and installed easily. Clamping them works best, but they only included 2 clamps and I had to goto the auto store halfway through the project. I installed them in my garage, if my exhaust hanget wasn't broken I could've done it in 2hrsn but I had to weld the hanger.Helpful (0)
April 08, 2019
Worst Experience Ever
I was super excited about getting these. My old cats were not sounding good (got a little bit of rattling when I revved up). So I finally decided to replace them. American muscle made it sound so simple as if it were a simple bolts on that should only take around 2 hours. This is defiantly not the case. The sizes of the ends of the cats are both different and does not even fit to the original exhaust properly (way too big). So if you are trying to use clamps like I did, you have to buy adapters and let me tell you that was a huge pain to get a good fit. Nothing seemed to work. I spent a whole day cutting and clamping (trial and error) until I finally got it to work. or at least I thought... because when I turned the car on, I could hear exhaust leaks. This was the worst experience I have ever had to deal with when it comes to car stuff. You are much better taking it to a muffler shop and getting someone to weld everything. The fact that they even give you 2 clamps and nothing else is a freakin joke. And this is a non-refundable item which means if you can't fit it right, you're out 200 bucks. Just spend the extra money and have muffler shop weld it in.Helpful (7)
February 22, 2019
2007 Mustang Gt
Work and sound great! The sound is a little more aggressive with stock exhaust mufflers.Helpful (4)
Hi can these cats pass smog in california?
These cats will not pass smog regulations in California.
I purchased these along with the off-road Pypes HPipes. After a few months of driving I got both a P0420 and P0430 code talking about the threshold isn't enough. Has anyone had issues with this? Also, what was the fix? My county does require emissions.
I would say to have the car diagnosed because there are a few systems that can cause this code for example o2 sensors failing, failing catalytic converters, running rich. After knowing what is wrong then we can help find a solution.
Will This Help The Exhaust Sound Better? Will replacing the stock cats with these help my V6 sound closer to a V8? i have dual flowmaster on it, and a K&N Cold Air Intake, it sounds pretty good right now but im wondering if putting these cats with help it alot
Def. I was was iffy at first but worth it you'll love the sound i have and im setting of car alarms all over lol.
Is welding these cats the only way to install them?
No, you can use the band clamps that are included with them for installation as well.
Will these fit my stock 2005 V6 Mustang? I have the stock y pipe and the stock headers.
The Pypes High Flow Ceramic Catalytic Converter Kit will not be a direct replacement for your stock cats, due to the angle they are mounted at. You will need some custom piping to complete installation.
Your OEM catalytic converters were designed for a set of criteria whereas the Pypes High Flow Ceramic Catalytic Converter Kit does not meet the same criteria and specs. These will be far more free-flowing and your current emission system will not work with this setup. As a result,you will need to either have this adjusted by a local dyno shop that performs on-site tuning or with a handheld tuner with custom tunes.
We offer a number of custom tuners, and a local dyno tuner can likely tune for these as well.
These do not need to be installed by a professional mechanic. We do advise that light to moderate mechanical skill is required for install.
Yes, the currently installed cats would have to be removed in order to install these. lnstall and removal method varies by model year.
These should work for you!
These would make your car slightly louder yes.
These are meant for boosted sets up but will work on an N/A car as well.
Those two can be used together, however custom work and modification would be required.
These are high-flow cats, and are not CARB compliant. We recommend reaching out directly to our Contact Center for assistance to find an item that fits your vehicle.
(approx) 4 Hours
Light to Moderate mechanical skill required.
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