I'm planning to add a set to my Challenger. It's the main reason I'm going with a fuel injection system (FiTech) instead of a carb as everything I've read indicates it's difficult/impossible for a carb to maintain the air/fuel ratio steady enough to prevent the converter from overheating.
Quote from: Dakota on June 08, 2018, 02:13:26 PM
I'm planning to add a set to my Challenger. It's the main reason I'm going with a fuel injection system (FiTech) instead of a carb as everything I've read indicates it's difficult/impossible for a carb to maintain the air/fuel ratio steady enough to prevent the converter from overheating.
Manufacturers started using cats in 74... They still used some carbs clear up to the late 80's.... I agree the FI is gonna do a better job of keeping the cat happy but plenty of carb equipped vehicles have run cats....
Wonder how much they cost?
I agree the eye watering fumes are a pain.
I switched to Fitech, it definitely made a difference, but didn't eliminate the smell.
Wonder where in the system it has to be, if I could add it to the rear near the tips, I'd consider them.
Unfortunately I'd bet they need to be near the manifolds.
Definitely near the front, they need the heat to start the reaction.....
https://www.amazon.com/MagnaFlow-53956-Universal-Catalytic-Converter/dp/B008W10KFY/ref=sr_1_1?ie=UTF8&qid=1528498891&sr=8-1&keywords=magnaflow+53956
Yes, as close to the exhaust manifolds/headers as possible...
And yes, the cats that I referenced above WILL work with a carburetor-equipped vehicle...
Finally, I believe that these are pretty close to US$400 each, "all-in", inclusive of shipping...
I'm out.................................
Quote from: Katfish on June 08, 2018, 04:37:02 PM
I'm out.................................
Because of placement? Or cost? if cost is a factor follow my link.... Magnaflow cats are $65 each from Amazon....
Placement, I have TTI exhaust that i already modded for the Fitech O2 sensor, not going to spend more money to get that all redone.
Fitech greatly reduce the rich gas smell i had with the carb.
And i'm not sure there's any room to mount something like that before the H-pipe.
I've been considering it for a couple years now.... if I do I'll likely get these ones.
https://vibrantperformance.com/catalog/product_info.php?cPath=1527_1326&products_id=2071
:haha: sorry but being my age, this brings back memories of all of the converters we cut out in the shop when they started putting them in. People would bring in their new cars and pay us to "get these things out of there".
Quote from: ToxicWolf on June 08, 2018, 05:10:13 PM
:haha: sorry but being my age, this brings back memories of all of the converters we cut out in the shop when they started putting them in. People would bring in their new cars and pay us to "get these things out of there".
The cats from the seventies absolutely choked engines..... The technology has advanced from that a little.... I gotta admit I love the smell of race fuel but few muscle cars have enough compression to justify the cost of race fuel, fact is most of us build knowing or hoping to be able to run pump premium.... And that stuff can smell nasty.... So cats can make sense for our toys..
Any idea on how/if it would affect the sound at all? Let's face it, the sound of the exhaust is a BIG part of the car.
There's some history on cat converters and way too much chemistry in this article:
https://eic.rsc.org/feature/the-evolution-of-catalytic-converters/2020252.article
As noted, the technology has advanced quite a bit from the early versions.
Does anyone know how long these last? :thinking:
Ehyeah, not going to happen on one of my Hot Rods. I guess I can see the reasons alright but I like these cars partly because they represent no rules to me. On the other hand I guess if your old car doesn't smell it will keep the Prius pussies from bioching about them.
I understand your point but personally I like to take 3-500 mile drives & when I get to where I'm going I prefer not to smell like I curled up with the exhaust pipe....
Ah: You convertible owners!
It's funny....I was thinking about the "smell" yesterday.....I'm driving my new Ram in moderate traffic with the sunroof open and the rear slider open.....then a Classic 60's Ford Comet drives by and cuts in front.....I followed him for awhile and could not believe the smell of the un-burnt fuel coming out of the thing.....I started imagining what it must have been like in the 60's -70's when EVERY car on the road smelt like that...... :'( talk about a headache looking for a place to happen :drunk:
Not convinced Cats will get rid of unburnt fuel smell. They will add the rotten egg smell. Cats job is to reduce Nox emissions. Our carb motors just run richer than the new cars. New cars run so much leaner is my understanding why they don't smell.
Quote from: tman on June 09, 2018, 09:20:04 AM
Not convinced Cats will get rid of unburnt fuel smell. They will add the rotten egg smell. Cats job is to reduce Nox emissions. Our carb motors just run richer than the new cars. New cars run so much leaner is my understanding why they don't smell.
Cats reducer NOX HC & CO...... But cats have their limits, if there's to much unburned fuel your gonna get a rotten egg smell... But if your running fuel injection that shouldn't be a problem.... & if it is your fuel injection isn't working right or the cat is on it's last leg....
I know this is an old thread, but was wondering if anyone did actually run any cats and if they did there job removing the smell.
Also, did they last and work properly?. Or horsepower lost?
I just bought one of these cat converters to put in my car. It had the smallest diameter that fit my exhaust pipe. My plan is to add it after the break-in oil is out of the engine. Assuming I can get the first one to fit, I'll buy the second.
I can't offer you a prediction on timing beyond "soon."
I'd caution anyone about buying a cat with ceramic honeycomb type guts. Years ago I built a pretty healthy Buick 455 /4 speed for my 1986 Buick and needed to run cats. I bought 2 Magnaflow cats and they lasted maybe 1/2 hour. Car ran great , lots of power it was crazy! I get home turn the car off and hear a rattle in the exhaust? After banging the exhaust to find where it turned out to be the cat. I took it off and the guts had melted into a ball and was moving around inside the shell. At that point I simply smashed it out( which was pretty easy to do) and reinstallled them so it looked like I had them .
Global Emissions Systems made a promising design but has stopped making them. They used a furnace brazed congregated guts that they claimed won't melt like ceramic ones can do. I'm not sure but Kooks header brand looks to be the same as the Global Emissions Systems cats marketed by Vibrant. I'd contact someone at Kooks to see what the guts are made of first before I bought one.
https://www.ebay.ca/itm/Vibrant-Performance-7830-GESI-UHO-Series-Catalytic-Converter/283803552376?hash=item4214028a78:g:2GMAAOSwlLReXrlC&vxp=mtr
https://kooksheaders.com/catalytic-converter1608
https://kooksheaders.com/catalytic-converter1606
Looks like Global Emissions Systems had a falling out with Vibrant Performance and have started there own marketing division. This is what I would get if I go thru with this idea.
https://www.ebay.ca/itm/GESi-G-Sport-High-Output-EPA-Catalytic-Converter-2-5-Inlet-Outlet-4-0-Body-OD/223747763810?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D1%26asc%3D20131003132420%26meid%3D4bef63d3e75c44b48f63d47740d4b892%26pid%3D100005%26rk%3D5%26rkt%3D12%26mehot%3Dpf%26sd%3D283803552376%26itm%3D223747763810%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWeb&_trksid=p2047675.c100005.m1851
https://www.verociousmotorsports.com/Shop-by-Category/catalytic-converters/GESi-G-Sport-Ultra-High-Output-Catalytic-Converters
Quote from: Dakota on March 24, 2020, 04:25:07 PM
I just bought one of these cat converters to put in my car. It had the smallest diameter that fit my exhaust pipe. My plan is to add it after the break-in oil is out of the engine. Assuming I can get the first one to fit, I'll buy the second.
I can't offer you a prediction on timing beyond "soon."
The converters have been installed. I have dual exhaust on stock exhaust manifolds out of my 340 with mostly 2-1/4" pipe except for the tips. The converter fit easily on the passenger side. On the driver side, there's not much room between the converter and the torsion bar. I'm going to add some heat shield wrap to the TB in hopes of protecting it.
I'm doing some other work on the exhaust system, then I'll get some photos posted.
I know these converters are likely going to foul over time given the additive package in the oil. Whether they work out not.... I'll post whatever happens.
I've always loved the smell of an old muscle car. It's not healthy But, neither is a big greasy hamburger once and a while.
Unless you're engine is very well tuned (for emissions), these will melt down and fail extremely quickly. The engine has to be running at stoich or lean for most of the time or they'll get so hot they'll glow and melt because of excessive hydrocarbons in the exhaust. Vacuum advance is probably going to be a requirement too. Any of you guys running lumpy cams, forget about it.
Quote from: Dmod1974 on April 25, 2021, 06:31:01 AM
Unless you're engine is very well tuned (for emissions), these will melt down and fail extremely quickly. The engine has to be running at stoich or lean for most of the time or they'll get so hot they'll glow and melt because of excessive hydrocarbons in the exhaust. Vacuum advance is probably going to be a requirement too. Any of you guys running lumpy cams, forget about it.
:iagree:
Along with what WildR/T said.
Gonna need EFI..
or you need to be a top notch carb tuner.
Pretty sure my DIY, seat of the pants carb tuning wouldn't cut it with cats. Runs nice though. :burnout:
Yea I have no issue with their addons if it helped with the stench AND did not reduce performance.
Mine is currently down for this same reason. Went for a longer than usual drive several months ago and the wife almost got sick from it.
Old mufflers and pipes gotta go along with replacing trunk gasket. Soon.
On the flip side, my 98 dakota running the factory computer and EFI system, retuned for a lumpy cam, is running without a cat. Because the tune is spot on, there is no "raw gas smell" from the exhaust. If your exhaust makes your eyes water, then your carb needs work. Use a wideband O2 sensor to dial in your carb, and use a data logger to monitor air fuel ratios across all the conditions the engine will see. Idle, part throttle cruise at various RPM and engine loading, WOT, etc. most folks put forth a minimum effort to tune their carb. Turn the idle mixture screws a bit here or there, change the jets for golden brown spark plug ceramics at WOT, done.