NMNorsse
OBS Enthusiast
My '88 k1500 5.7 with 60k original miles needs a new catalytic converter and muffler. They're 35 years old, they're getting loud and everything has pin holes along the bottom center. My guess is that condensation built up and made the holes over those many years the truck was parked.
The age of the truck exempts it from emissions requirements. However, I will still install a catalytic converter even though there is no down-stream O2 sensor to keep the stink down and do my part for the environment. Plus, I may not always live in this state.
Have read many many posts and threads here about the exhaust which I summarize as follows:
Replacing the cast iron heads with headers can give you back some power. Long tube headers on a 4x4 is tough. The early TBI Y-pipe is not great and replacing it can help. Replacing the OEM pellet Catalytic Converter with a high flow cat (or 2 high flow cats) can help too. Running it from the headers to at least the cat in 2.5" is best. There is only 1 O2 sensor (single wire) and I have to put it in whatever I do.
My engine is stock and although someday I'll replace the heads, the cam and chip it, I'm focused on today.
Either I'm old, my hearing is too sensitive or I like my music too much. Whatever it is, I want to make it quieter. I don't need a rasp, rumble or anything. It would be nice if this thing were as quiet as a Tesla but that ain't in the cards so I'll settle for it being as quiet as a new Silverado.
I am planning on JBA stainless shorties, a stainless 2.5" y-pipe, a high flow cat or 2, eliminating the AIR pump and lines, and using a long muffler like the 37" Walker SoundFX 18890 or 30" Walker Quiet SS 21431. I plan on keeping the tailpipe where the factory put it, a side exit behind the passenger side rear well.
Would true duals with 2 cats and 2 mufflers be better in terms of performance and quietness?
Should I add a resonator between the cat and muffler, after the muffler?
Does anyone have any suggestions about specific mufflers to quiet this down without impacting the performance gains from headers, y-pipe and high flow cat?
Am I better off with absorptive (straight through), reflective or hybrid muffler(s) if my goal is both performance and quietness?
If true duals are the way to go, what about an x-pipe or h-pipe to scavage?
Thank you all in advance for your insights.
The age of the truck exempts it from emissions requirements. However, I will still install a catalytic converter even though there is no down-stream O2 sensor to keep the stink down and do my part for the environment. Plus, I may not always live in this state.
Have read many many posts and threads here about the exhaust which I summarize as follows:
Replacing the cast iron heads with headers can give you back some power. Long tube headers on a 4x4 is tough. The early TBI Y-pipe is not great and replacing it can help. Replacing the OEM pellet Catalytic Converter with a high flow cat (or 2 high flow cats) can help too. Running it from the headers to at least the cat in 2.5" is best. There is only 1 O2 sensor (single wire) and I have to put it in whatever I do.
My engine is stock and although someday I'll replace the heads, the cam and chip it, I'm focused on today.
Either I'm old, my hearing is too sensitive or I like my music too much. Whatever it is, I want to make it quieter. I don't need a rasp, rumble or anything. It would be nice if this thing were as quiet as a Tesla but that ain't in the cards so I'll settle for it being as quiet as a new Silverado.
I am planning on JBA stainless shorties, a stainless 2.5" y-pipe, a high flow cat or 2, eliminating the AIR pump and lines, and using a long muffler like the 37" Walker SoundFX 18890 or 30" Walker Quiet SS 21431. I plan on keeping the tailpipe where the factory put it, a side exit behind the passenger side rear well.
Would true duals with 2 cats and 2 mufflers be better in terms of performance and quietness?
Should I add a resonator between the cat and muffler, after the muffler?
Does anyone have any suggestions about specific mufflers to quiet this down without impacting the performance gains from headers, y-pipe and high flow cat?
Am I better off with absorptive (straight through), reflective or hybrid muffler(s) if my goal is both performance and quietness?
If true duals are the way to go, what about an x-pipe or h-pipe to scavage?
Thank you all in advance for your insights.
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