Magnaflow Cat
#11
06-19-2008, 09:58 AM
#12
06-19-2008, 11:10 AM
#13
06-19-2008, 11:56 AM
RE: Magnaflow Cat
i have all the same questions that you do, but no firm answers.
my setup is the same as yours, and i'm wondering if i can just saw off the cat in front of the front weld and behind the back weld, then fit the right length cat into the hole, and either clamp it in or weld it in. the o2 bungs are in the pipes, so i'd just leave them alone.
i found a nice assortment of universal cats here...
it looks like they come in 10, 12 inch bodies, with 14-16 overall lengths.
the "eastern" brand is a lot easier to browse than the magnaflow, and list dimensions.
http://www.catalyticonverters.com
i'm thinking that the old cat may have some significant scrap value, $20-30-40, as a read about people stealing them like crazy.
my setup is the same as yours, and i'm wondering if i can just saw off the cat in front of the front weld and behind the back weld, then fit the right length cat into the hole, and either clamp it in or weld it in. the o2 bungs are in the pipes, so i'd just leave them alone.
i found a nice assortment of universal cats here...
it looks like they come in 10, 12 inch bodies, with 14-16 overall lengths.
the "eastern" brand is a lot easier to browse than the magnaflow, and list dimensions.
http://www.catalyticonverters.com
i'm thinking that the old cat may have some significant scrap value, $20-30-40, as a read about people stealing them like crazy.
#14
06-19-2008, 12:32 PM
RE: Magnaflow Cat
I went ahead and ordered a 3" Magnaflow Cat from Summit. I want to do exactly whatdhvaughan said he wanted to do so we will see how it works. I also ordered 2 new Bosch front o2 sensors from Rock Auto and a rear o2 Simm although it's on backorder. I didn't want to risk setting a light off. Should I wait until I get the o2 simm and do all 3 at once or is it fine to put the front ones in and just put the rear simm in whenever it comes? I just ordered the simm to be 100% on the safe side. I'm hoping the shop can weld the cat on like I want then I will change the o2 sensors. Hopefully this helps the power of this truck.
#15
06-19-2008, 12:47 PM
Legend
RE: Magnaflow Cat
dhvaughan,
Do you still have the stock muffler? You can check and see if it knuckles down at the muffler too. On the 3" pipe I had, the Cat and the muffler both knuckled down to 2.5" inlets and outlets. You can also cut a 3 inch circle out of cardboard and hold it next to the pipe and see it matches size, just mark the top and bottom of the cardboard circle with a line going toward the center and hold it directly behind the pipe from your point of view. If you can clearly see the marks, and not just the edges of the circle then the pipe is smaller.
Do you still have the stock muffler? You can check and see if it knuckles down at the muffler too. On the 3" pipe I had, the Cat and the muffler both knuckled down to 2.5" inlets and outlets. You can also cut a 3 inch circle out of cardboard and hold it next to the pipe and see it matches size, just mark the top and bottom of the cardboard circle with a line going toward the center and hold it directly behind the pipe from your point of view. If you can clearly see the marks, and not just the edges of the circle then the pipe is smaller.
#16
06-19-2008, 12:48 PM
Legend
#17
06-19-2008, 12:52 PM
RE: Magnaflow Cat
ok, you're the guinea pig....
correct me if i'm wrong, but in your pics i only see 1 front o2 sensor just downstream of where your 2 exhaust pipes merge (the Y).
i'd do 1 step at a time. replace cat and see if it runs/acts any different. then replace upstream 02 (they're sort of expensive, and also affect fuel trim). then if, and only if, a CEL comes on regarding inefficient cat, i'd put in the 02 sim. since a cat is a cat, and does what its supposed to do, i'd think you wouldn't need the sim. generally the sim is used when you remove or gut the cat.
which part number cat did you order ?
dimensions ?
correct me if i'm wrong, but in your pics i only see 1 front o2 sensor just downstream of where your 2 exhaust pipes merge (the Y).
i'd do 1 step at a time. replace cat and see if it runs/acts any different. then replace upstream 02 (they're sort of expensive, and also affect fuel trim). then if, and only if, a CEL comes on regarding inefficient cat, i'd put in the 02 sim. since a cat is a cat, and does what its supposed to do, i'd think you wouldn't need the sim. generally the sim is used when you remove or gut the cat.
which part number cat did you order ?
dimensions ?
#18
06-19-2008, 12:58 PM
RE: Magnaflow Cat
ORIGINAL: aim4squirrels
You can also cut a 3 inch circle out of cardboard and hold it next to the pipe and see it matches size, just mark the top and bottom of the cardboard circle with a line going toward the center and hold it directly behind the pipe from your point of view. If you can clearly see the marks, and not just the edges of the circle then the pipe is smaller.
You can also cut a 3 inch circle out of cardboard and hold it next to the pipe and see it matches size, just mark the top and bottom of the cardboard circle with a line going toward the center and hold it directly behind the pipe from your point of view. If you can clearly see the marks, and not just the edges of the circle then the pipe is smaller.
yes, i still have the stock muffler and cat.
also, to get really precise, you can buy a plastic caliper for only about $1. damn, now i've got to go crawl under the truck....
#20
06-19-2008, 01:16 PM
Legend