Ca smog

[1979cheyenne]

i have a 79 Cheyenne originally a I-6 but had a crate good wrench 350 installed in 94, what exhaust setup can I run and still squeeze by our not so awesome Cali smog rules? Looks like an 8th grader welded this exhaust setup and the pipe gets reduced twice I believe or once I can't remember, after the cat down to 2" single outlet and the cat outlet looks considerably larger, can I remove this converter and run the same size from cat to muffler? Should I get a muffler with single inlet dual outlet? I'm not sure if it's required for some reason. And I'm pretty sure I can't put true duals on

[Irish_Alley]

Can't really help cause I'm not familiar with cal smog. But can tell you this the smoother you exhaust runs the more power it can handle.

[LTZ C20]

You can change anything you want AFTER the cat converter. You can rebuild what's before the converter but it has 2 be exactly the same as original. So new pipes and converters is ok but you have to have the same number of converters and they have to be in the same place. I believe MagnaFlow makes performance cat converters you could use. You can put headers on but they have to be smog legal, so they have to have an O2 sensor bung if needed but being a 79 the only thing you should have is the AIR injection tubes on both sides and the heat flapper on the passenger side. Most major header brands make a smog legal header that comes with a CARB sticker. After the converters it's free game but you HAVE to have a muffler.

[1979cheyenne]

Thank you for the info on cat back, but I still wonder about the before the cat. because this engine wasn't factory, it was a 94 crate 350 in an original I-6 truck and I'm pretty sure you couldn't use the exhaust from the 6 so what would be "factory exhaust" for a 94 crate engine?

[Irish_Alley]

Most states idk about cal. But most are OK with putting a newer engine as long as it came in that series in an old truck. Just cause of better emissions

[LTZ C20]

Like Irish said, a newer engine is ok. The exhuast should be the factory configuration for 79 not 94. 94 exhuast system is not the same setup as 79. It will not pass with a 94 setup on the exhaust.