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YOUR RESEARCHOpinions about Catalytic converters
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Seems that designs have changed a bit over the past 14 years.
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Quick question for you as I look at my 14 year old cats and mufflers that will need to be replaced soon.
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(recommended for street use) Next, is our supercups which is about 70% louder than the stock mufflers.
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Catalytic Converters have a 8 year 80k mile Federal Warranty in the USA, I can say as a dealership tech for over 40 years that replacing Cats under warranty is very rare even on the Porsche Driving School cars that were tracked daily.
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Catalytic Converters have a 8 year 80k mile Federal Warranty in the USA, I can say as a dealership tech for over 40 years that replacing Cats under warranty is very rare even on the Porsche Driving School cars that were tracked daily.
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I have an 02 4s and have some questions about CATs. It seems like everyone has a conflicting opinion about them. So, I would love to hear your experiences.
1. Do OEM cats not stand up to track use as well as hiflow cats? I have heard that they don't and also that they do. I track my car six or seven days a year and seem to burn through OEM cats every couple of years or so. Is this everyone else's experience?
2. Do hiflow cats really make a noticeable difference in performance? Do they sound any different with the same exhaust?
3. I have a sport exhaust and am very happy with how my car sounds. I do not want to switch out the entire exhaust. But think I might be better off with hiflow cats. Anyone have any recommendations for what brand to use?
Catalytic Converters have a 8 year 80k mile Federal Warranty in the USA, I can say as a dealership tech for over 40 years that replacing Cats under warranty is very rare even on the Porsche Driving School cars that were tracked daily. If you are burning up Cats every few years, there is something wrong that is NOT your Cats..
I have the FVD 200 cell cats on my car with the FVD sport mufflers. Had them on for probably 14 years. Great sound and durability. Per FVDs recommendation, they said to use my Oem headers. 55k miles on the car with probably over 80+ track days. Not certain if I ever got any additional performance from exhaust, plenum, throttle bodies, but you do get much better sound. Most importantly, you get quite a bit of weight loss with aftermarket cats and mufflers versus Oem. I would buy them again and will probably need to in the next year or two. As a side note, one of the easiest ways to make your car faster is to reduce weight any way you can. Exhaust, brake kit and racing seats can do it very quickly.
All my shop did was bolt on the FVD cats and mufflers and it was good to go. Call Rhonda at FVD. She is/was the person who helped me out. Last I checked, she is still there. She can walk you thru the logistics. My understanding was the cars Oem software would work thru everything. In my case it did without any problems.
Hey Guys,
Phil from Fabspeed here.
When talking about cats especially aftermarket cats there are some very important questions to ask.
6-7 days a year at the tracking and you are burning up your Oem cats those have to be some great track days. The oem cats get much hotter than aftermarket cats, so it does make sense that you are burning them up.
When it comes to aftermarket cats; Size, type, and CEL count all matter especially if you are taking the car to the track a couple times a year.
At Fabspeed Motorsport we use the biggest 200 cell directional HJS catalytic convertors possible in our setups.
What does this mean for you?
1. HJS is the world leader in Catalytic convertors. They are the gold standard when it comes to an aftermarket cat.
2. Using a larger cat gives you a bigger surface area to distribute heat more evenly.
3. The cat being a directional cat instead of a universal flow, is set up so there are more precious metals in the direct exhaust flow instead of coating the cats all over to help give you longevity.
4. the 200 cel is much more free flowing over the 600 cel from factory. So they are not as hot. However compared to 100 cel you will not receive a cel when driving around.
I will reach out to if you have any other questions.
Good info Phil.
Quick question for you as I look at my 14 year old cats and mufflers that will need to be replaced soon.
Interested in weight saving, durability, performance, sound, and no computer problems on the track as well as to drive the car around town locally. What this means is that I want to pass state inspection every two years and not have to change exhaust systems.
What Fanspeed 200 cell cats and muffler do you recommend. Do we get any performance enhancement adding one of your headers. If so, which one?
Appreciate your insight.
For the 996 We only have two set up for the cats and that is cats or no cats.
Sport cat x-pipe
This is the only setup that will pass emission in every state except Ca.
As far as the muffler that really depends on how loud you want to get maxflows are the quietest of our system at about 25% louder over the factory mufflers. (recommended for street use) Next, is our supercups which is about 70% louder than the stock mufflers. ( track with the occasional street use) Lastly, that would be our muffler bypasses which is 100% louder than the stock mufflers. (Track use)
It would be very beneficial to do headers however it can also a bear of a project. The studs are a different metal than the block and because of this the studs tend to get rusted in and very difficult to get out.
Plan on keeping the car. Every year I do a project or two to replace, upgrade something on the car. It's inevitable that I will need to replace 14 year old cats and mufflers someday in the next few years. I plan on studying the new exhaust designs that are out today. Seems that designs have changed a bit over the past 14 years. We all want more performance, less weight, more durability, plus a sound that matches our criteria. It will take me a year or two to figure out the best way to get it with what's available on the market.
My '85 928 still has factory converters and many others do too. Unless the material holding the internals of the converter fail or the engine destroys them, they will last for the life of the car. I know the feeling to replace old parts but the converters are not something I would spend money on. Most aftermarket converters are made of less quality than the OE and will not last long. My 996 has aftermarket headers and muffler (Billy Boat is the brand for both) and they make the car sounds really good. I would suggest first to just to replace the mufflers as they do rust at the seam and eventually fail and then, if you need a higher pitch sound, get a set of headers that have a proper collector at the ends. If you mufflers are still in good shape, have them modified to get more sound. That's what many here did including two of my buddies and the results were really good for very little money.
