Really? I know the trucks of that era used 2 way. That comes as a surprise. The nerd in me is genuinely curious about how the CCC operated.
Catalytic converters vs small resonators?
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Really? I know the trucks of that era used 2 way. That comes as a surprise. The nerd in me is genuinely curious about how the CCC operated.
A computer controls the air fuel mixture in special carburetors via a solenoid operating the main rod jets, maintaining a 14.7 to 1 ratio except during power enrichment mode (WOT). These carburetors also feature a TPS. Also the smog pump pumps oxygen into the cat converter after warmup. Its very different from the truck version.
The old style 3 way cats do not generate their own oxygen like modern 3 way cats. Its why older cats have air tubes.
Environmental virtue signalling notwithstanding.
If a Hellcat or Z06 or the like can make 700+hp through a pair of cats there is no reason not to use them. I have them on everything except the Monte simply because there wasn't an affordable 4" option at the time I built the exhaust. I may add one later for compliance reasons.
They can definitely address certain frequencies and NVH issues. But, this is also why cars come with cats, resonators, active valves, and mufflers these days because there are regulations which demand them.
If a Hellcat or Z06 or the like can make 700+hp through a pair of cats there is no reason not to use them. I have them on everything except the Monte simply because there wasn't an affordable 4" option at the time I built the exhaust. I may add one later for compliance reasons.
They can definitely address certain frequencies and NVH issues. But, this is also why cars come with cats, resonators, active valves, and mufflers these days because there are regulations which demand them.
They must have lacked that bit in the middle that stores oxygen from a lean cycle then? That would make sense.
To be clear, this carb is probably a hair rich at idle, lean at part throttle but easily adjusted to much richer and probably rich full throttle. I have to add an O2 bung somewhere anyways for an AEM wideband O2 setup to properly tune the Qjet anyways, especially when the new motor is done. Pretty sure my 70 Cutlass S will pass 1970 emissions as is. As long as they don't plug, not super concerned about their function, they just tick off multiple boxes. If I get a 5 decibel sound reduction it should be enough.
They will be happier if you keep the engine closer to stoich, but you'll see better fuel economy by leaning the motor out. Only concern there would be melting the cats. My friend melted his aftermarket cats on an LS1, to this day we're not sure why. Maybe they just sucked?
If the fuel mixture or ignition is off it can send excessive unburned HCs into the cat where they can burn and melt the cat down. Rich or lean can do it.
On a side note, Police package cars like my P71 do not come with resonators. Just cats and mufflers.
On a side note, Police package cars like my P71 do not come with resonators. Just cats and mufflers.
I have a stinking suspicion that my TBSS killed it's kitties. I call them Schrödinger's cats because I am not opening the box to find out.
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