Cats on TTI exhaust system

[n00blike]

First, who do you know pouring oil down the drain? Damn.

I would say if you really want to dig into it, learn where the data comes from, how to tune for it, like to see improvements over time, then a carburetor is for you.
If you want to really dig into efi and learn to tune and see improvements over time you can do that. Both, changing tune as need be.
If you want to hit the easy button, get the efi (or carb) and have a pro install and tune it to your application. Take it back to them if you ever need.

One thing we didn't discuss was how far could you be away from home. EVEN IF you learn your EFI to a gnats *** you could break down and be waiting for days on replacement parts. Roadtrip sound good? With a carb you could get any repair parts you need in almost any town. Dave Freiberger just switched to the Slayer 600 vacuum secondary carb like I am using. I want to drive my Duster like he does, I just need a GV for road trips. I was on the fence with the carb/EFI and then my dad had the problem with Holley Sniper. What would DF do? Well, he went to the carb I already have. Since I wanted all the things EFI gives you I decided to get the gauges I needed for the data I need to tune a carb properly.
My only thing against EFI is the getting stranded thing. I would just want to be able to be run back to the house to grab my truck and trailer. My prospective EFI car would not go on overnighters without being trailered. Think race car.
With the carb, A/F ratio gauge and O2 sensor, vacuum, and tach you will be able to run as clean as EFI in most every situation. Learning the tuning and equipment better is going to be required in both cases.

Being able to find parts locally has been something I have thought about, but I recently had to do a factory front disk brake job and replacement parts were a few days out. Seems like in my area those parts are already being phased out. I guess it is a 50 year old car...

 

[MopaR&D]

I'm also a mechanical engineer and learned quite a bit about engine emissions in grad school, especially in natural gas engines that have to deal with water vapor and H2S in the fuel and particulate emissions from diesels.

The real solution? Drive less. The real reason we got to this point is due to consumerism and capitalism manufacturing demand for stuff we really don't need and making everyone dependent on it. I find it ironic that California is so environmentally-focused but also has some of the largest road and highway systems in the world when they could've built trains to get people where they need to go much more efficiently.

I love cars but I detest commuting to work every day in traffic dealing with all the idiots who really shouldn't be behind the wheel of a 2-ton steel box (nowadays 3-ton-plus pickup trucks and SUVs just to move around one person). I'd rather take a train to work during the week and just have a fun car to drive on the weekends.

 

[mopowers]

I find it ironic that California is so environmentally-focused but also has some of the largest road and highway systems in the world when they could've built trains to get people where they need to go much more efficiently.

They're working on it - and what a money pit/**** show that's been with nothing to show for it. Some things that sound good in theory just aren't practical in the real world.

 

[MMissile]

If you have the expendable funds, Gen-3 and a 5 or 8 speed. Light cars, don't need the 8 speed. Get your power, and cleanly.

 

[n00blike]

I'm also a mechanical engineer and learned quite a bit about engine emissions in grad school, especially in natural gas engines that have to deal with water vapor and H2S in the fuel and particulate emissions from diesels.

The real solution? Drive less. The real reason we got to this point is due to consumerism and capitalism manufacturing demand for stuff we really don't need and making everyone dependent on it. I find it ironic that California is so environmentally-focused but also has some of the largest road and highway systems in the world when they could've built trains to get people where they need to go much more efficiently.

I love cars but I detest commuting to work every day in traffic dealing with all the idiots who really shouldn't be behind the wheel of a 2-ton steel box (nowadays 3-ton-plus pickup trucks and SUVs just to move around one person). I'd rather take a train to work during the week and just have a fun car to drive on the weekends.

California is not as liberal as people think, it was the 10th state to get same sex marriage rights (9 years after the first). Funds for homeless, public transportation, and affordable housing always seems to end up in someone's pocket and not in the programs.

My commuter car is a small reliable 4 cylinder, it would be nice to have better public transportation, but no one makes money off it so I don't think that will happen.

 

[RustyRatRod]

California is not as liberal as people think, it was the 10th state to get same sex marriage rights (9 years after the first). Funds for homeless, public transportation, and affordable housing always seems to end up in someone's pocket and not in the programs.

My commuter car is a small reliable 4 cylinder, it would be nice to have better public transportation, but no one makes money off it so I don't think that will happen.

I don't care how liberal it is. I care that it's a complete financial failure and worry that might be contagious.

 

[dadsbee]

Lets keep politics out of a general forum post...

 

[RustyRatRod]

Lets keep politics out of a general forum post...

I agree. That was the last of it from me.

 

[sr71mopar]

Small block A bodies run better in California because, on average, we have denser air.

 

[go-fish]

Being able to find parts locally has been something I have thought about, but I recently had to do a factory front disk brake job and replacement parts were a few days out. Seems like in my area those parts are already being phased out. I guess it is a 50 year old car...

My hang up is the theoretical multi-state road trip. I wouldn't leave without doing a brake job if needed. I'm talking about breakdown potential and severity. Let's take a car and assume it's all sorted out, EFI or carb, and poop hits the fan with your fuel system.
Potentials-
EFI: In-tank fuel pump, 10 micron and 100 micron filters, regulator, ECU. All of this is a few days in the mail. Definite flatbed service and a disruption to a trip.
Carb: Fuel pickup, fuel pump, filter. At a parts store or one that's near. These are also cheap enough to carry a spare along with a small parts and tool kit.

Carb issues can be slower in stopping you in your tracks than EFI's often sudden stoppage or non-start issue.

Either way, to do what you want to do either a carb or EFI will do it. Some worthwhile advice has been given. Engine swap to a modern engine platform(most likely with EFI), run natural gas or an ethanol blend, overdrive transmission, and the catalytic convertors and you will be doing as good as you CAN do. Look through Muscle Car Solutions content for EFI vs Carb, tuning for both, and understanding it all.

 

[MopaR&D]

Might have been mentioned already but modern 3-way cats work best and last the longest when the AFR fluctuates between slightly rich and slightly lean during cruise. This is obviously not really possible with carbs. Also not having EGR makes a cat not last as long as it causes more NOx to be produced during combustion. When I lived in CO my daily was a 1993 Cherokee with the 4.0L straight-six. It had port EFI but no EGR. Every 3-4 years I had to replace the cat because it wouldn't pass emissions testing. Since it didn't have EGR it loaded the cat with more NOx and caused it to go bad faster than other cars that had EGR. I also would buy aftermarket cats instead of OEM due to cost and they don't last as long because they have less catalyst material in them (that's why they're cheaper).

 

[jbc426]

Hello, I have a 74 Duster with a 360 and TTI headers. I'm looking to get the TTI exhaust system, but I would like to add catalytic converts. Does anyone have experience running the TTI 3" exhaust system with catalytic converters? How was the fitment?

These are the ones Rusty prefers. The 100CEL are much higher flow than any of the stock ones which are about 600 to 800 CEL. They have a metal honeycomb instead of ceramic for increased durability etc. You can actually see through them, and they still work. It takes about 3 minutes for them to "light off", and then no more smell or shellfish toxins.

It eliminated the un-burned hydrocarbon smell from the high overlap cam I was running. I have a convertible so it was bad when cruising and the wind was blowing the fumes into the car instead of away.

There was no noticeable sound or performance change after installing them, and no more fumes. They do get very hot, so be careful where you put them.

 

[remytherat]

3-way cats work best and last the longest when the AFR fluctuates between slightly rich and slightly lean during cruise.

Yes.

Three way cats deal with HCs, CO, and NOx. The first two need to be oxidized, the third needs to be reduced. Oxidation and reduction need different concentrations of oxygen, requiring both rich and lean conditions. That said, if eliminating HCs is the goal (because of the odor), you only really need the lean condition.

 

[65 Cuda 340]

I'm also a mechanical engineer and learned quite a bit about engine emissions in grad school, especially in natural gas engines that have to deal with water vapor and H2S in the fuel and particulate emissions from diesels.

The real solution? Drive less. The real reason we got to this point is due to consumerism and capitalism manufacturing demand for stuff we really don't need and making everyone dependent on it. I find it ironic that California is so environmentally-focused but also has some of the largest road and highway systems in the world when they could've built trains to get people where they need to go much more efficiently.

I love cars but I detest commuting to work every day in traffic dealing with all the idiots who really shouldn't be behind the wheel of a 2-ton steel box (nowadays 3-ton-plus pickup trucks and SUVs just to move around one person). I'd rather take a train to work during the week and just have a fun car to drive on the weekends.

I agree. Love cars, hate traffic. Best part about being retired is I don't have to commute to work during rush hour traffic every day. And gas doesn't cost nearly as much when you don't have to buy so much of it.

 

[RustyRatRod]

These are the ones Rusty prefers. The 100CEL are much higher flow than any of the stock ones which are about 600 to 800 CEL. They have a metal honeycomb instead of ceramic for increased durability etc. You can actually see through them, and they still work. It takes about 3 minutes for them to "light off", and then no more smell or shellfish toxins.

It eliminated the un-burned hydrocarbon smell from the high overlap cam I was running. I have a convertible so it was bad when cruising and the wind was blowing the fumes into the car instead of away.

There was no noticeable sound or performance change after installing them, and no more fumes. They do get very hot, so be careful where you put them.

View attachment 1716486665

Actually, I prefer none, but I guess if I just HAD to...

 

[RustyRatRod]

My hang up is the theoretical multi-state road trip. I wouldn't leave without doing a brake job if needed. I'm talking about breakdown potential and severity. Let's take a car and assume it's all sorted out, EFI or carb, and poop hits the fan with your fuel system.
Potentials-
EFI: In-tank fuel pump, 10 micron and 100 micron filters, regulator, ECU. All of this is a few days in the mail. Definite flatbed service and a disruption to a trip.
Carb: Fuel pickup, fuel pump, filter. At a parts store or one that's near. These are also cheap enough to carry a spare along with a small parts and tool kit.

Carb issues can be slower in stopping you in your tracks than EFI's often sudden stoppage or non-start issue.

Either way, to do what you want to do either a carb or EFI will do it. Some worthwhile advice has been given. Engine swap to a modern engine platform(most likely with EFI), run natural gas or an ethanol blend, overdrive transmission, and the catalytic convertors and you will be doing as good as you CAN do. Look through Muscle Car Solutions content for EFI vs Carb, tuning for both, and understanding it all.

Don't forget all the modern engine counterparts have ways to run carburetors. But they lack distributors, so you must use coil packs and crank triggers and such. More electronics to get wet, hot and fail.

 

[92b]

Don't forget all the modern engine counterparts have ways to run carburetors. But they lack distributors, so you must use coil packs and crank triggers and such. More electronics to get wet, hot and fail.

These are the same concerns people had when making the transition from points to electronic ignition years ago.