I may be forced to go back to having cats in the car.
What companies / products are available out there? I have Miltek catless DP’s i plan on just modding to get the cats put in there. Unless i can just add them to the exhaust line somehow?
I remember hearing a few horror stories of some basically disintegrating and such so i would like to stay away from that type of product.
So what are my options?
Lets get a full list out and a rating.
Great question and good idea. I too will be adding cats to my JHM set up prior to installing it on my car. Albeit I plan to use flanges so I can swap them in and out when at the track or whatever other reason I choose. That being said, I know 034 carries some quality hi-flow cats, not sure of the manufacturer though. I remember a lot of people praising the HJC hi-flow cats in the past, not sure if this is still considered a quality component. On the less expensive side of the coin, Magnaflow offers some hi-flow (100 cell, 200 cell, 400 cell etc) cats for decent pricing. No clue how they hold up long term or perform.
Looking forward to hearing from the informed with experience.
JHM must use 034 (although I haven’t confirmed that). I really have no idea about the catalytic converter market. They’re weird.
Why on earth are they so expensive? JHM charges something pretty modest but most exhaust companies, when you elect to have catted downpipes, add in a really big nickel. Sometimes $1000 difference vs. catless.
I do know that whoever Milltek uses may not be a great choice (historically anyway)…lots of complaints about them failing after a few years.
Stock cats are EXCELLENT whatever they are. They last, and flow very well.
http://www.randomtechnology.com/index.html - Great cats, no experience though as I never got to install them on my car. I have heard they are great though.
Great thread. I too am interested in this.
Anyone have any idea if 100 cell cats eliminate the smell. Or do we have to go 200 or 400 to accomplish a more “civilized” smelling exhaust? Thing is, my car runs much better catless than it did with the piggies. In better I mean free. I want that feel but less smell.
Also, if i did this I’d probably put them on the very end of my DPs right before they mate to the cat back. That way they could be swapped in and out quite easily. A small overall diameter would be a must in that location.
I wonder how close they have to be to the motor for the gasses to still be hot enough for the cat to work correctly. I wonder how it would affect the job of the x-pipe if you were to put it at then end of the downpipe, which is only 12" away from the beginign of the x-pipe.
The cats are all just rebranded, so don’t worry about stick to 034 because they make stuff for Audi’s. Magnaflow HFC’s are extremely popular in the musclecar world. So are Dynomax
I was always under the impression that the inherent high cost of cats was due to the precious metals used.
I know the RS4 “MAIN” cats are excellent and are 400 cell count. To be honest, I don’t really care what cell count the cat has or who makes it as long as it performs well and negates the smell so my garage doesn’t stink up the house etc.
The exterior diameter will play a roll due to where they will be installed. I’ll probably contact CV to discuss details on location etc. Or maybe he will chime in here and share his experience/opinion.
^^^contact Dan…he will probably offer you JHM cats installed for a fair price.
That’s what I thought too NY. I would be using that style cat. Ceramics don’t seem to hold up very well from what I’m reading. I want the least amount of cat it takes to get rid of the smell. Screw SMOG.
Good point Joe. We need help on this one. Bring in the experts!
What cats do JHM use for their longtube headers?
Do a set of these even exist in the wild?
I guess it’s an engine pull to change the cats when you’ve got headers.
au contraire, it’s really easy to change downpipes when you have headers. JHM headers come with mini downpipes, and if you want cats, they’re in the mini downpipes.
The headers reach out quite a ways from the engine, so where they mate up with the mini downpipes is down under the car, rather than where traditional downpipes/cats are attached to the stock manifolds which are way up tucked away in the engine bay.
Accessing RS4 headers is also quite a bit easier than B6/7 S4 (although not quite as far out as the JHM headers as the stock RS4 triy headers aren’t nearly as long.
Here’s ngng’s headers/minidownpipes with cats
http://gallery.achtuning.com/main.php/d/28387-4/DSC_7992sized.jpg
I must have drooled over the below picture 1000 times but it never occurred to me that those little pipes would be more, not less, accessible. That’s very cool.
I still need to get the most out of the piggies though, driver mod first to beat saki’s old MPH with them on. LOL.
http://jhmotorsports.com/products/pictures/Headers/JHM_B6-B7_S4_Longtube_Headers.jpg
Oh and what cats do they use in there?
[quote]-Catalytic Converters: From the drop down box below you can select No Catalytic Converters - Best Performance or Race Catalytic Converters(Spiral Metallic Substrate) - Better performance.
[/quote]
dunno
I’ll bug Dan. They do tons of business with 034 so that’s a good guess. If I buy a JHM exhaust it will be catted.
p.s. here’s the stock manifolds…you can see how far they don’t reach!
yeah O2 sensors and cats are very simple on the jhm headers… they are basically what some people refer to as hot swap pipes and really aren’t a new idea but are great regardless
you mean hot swap pipes weren’t invented recently? lol
That’s pretty sweet either way - have one set with cats for the e-test and another for everyday use. Keep one catted set to pass around different people…
I will contact Dan but what do you he would offer me JHM cats installed for a fair price? You know I already have the DP’s & cb. I would have to have a local exhaust shop install them for me with the flanges. Or did you mean something else? Like ship the DP’s back to JHM and have them install them?
yes that’s what I meant.
could be prohibitively expensive with the shipping I guess. Call him though…nobody will know better than him what works on the downpipes they designed. Maybe Ben lol.
I’m going to order some of these http://www.magnaflow.com/02catalytic_converters/02product/displayuniversal.asp?universal=59956 Mustang guys seem to like them.
Call me a puss but the smell is getting a little too obnoxious for me.
EDIT
It appears that those are 300 cell count. No good. Need to find 100s. Crap