Time for a new exhaust

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adamj

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As you can see, I need a new exhaust system. Holes everywhere, hangers cracked, and it still has the old pellet-style cat.
I stopped by a local shop, who quoted me $650 for a new system after the y pipe back. That includes a new "modern" cat, a flowmaster 40 series muffler, and tailpipe, all welded and new hangers.

A few questions:
1) What is the correct size pipe for this engine? (sb350 with single exhaust, cat and 4wd)
2) Thoughts on a dual exhaust for a 4wd truck? I asked if I could have a dual system, but the shop said they could not do that due to emission laws. (I am in an emissions region) Even 2 cats and 2 mufflers, they said not possible due to laws.
3) Y-pipe. This pipe that connects the two banks into one looks strange and hangs low, lower than the transmission crossmember (see pic, is that normal??) It's just asking to be scraped on a rock or something. Is there a better option? Or does this have to be shaped this way? Shop said y-pipe was fine and does not need replacement. I read about a new coupler that alleviates some restriction. Is this something I should look into or is it not worth it?
4) Muffler/sound: deciding between going stock sound for ultimate quietness, or something else - I like that low "boat" sound a lot, but don't want something too loud, or even remotely loud.


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Old77

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is that rebar that was being used as the hanger?
 

adamj

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is that rebar that was being used as the hanger?

It sure looks like it! I'm not sure, but I don't think that's stock.
 

Old77

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I'd say you're probably right LOL Always entertaining to see what previous owners have done and that you're now trying to fix.
 

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I would say a single 2.5" exhaust would be sufficient if your engine is near stock.

If it were me and there was no price difference, I would go 3" in your situation. It will be louder, but I don't think it would be too obnoxiously loud.

I don't know how handy you are, but you could also get a manifold back dual exhaust kit and install it yourself. You could probably get it done for $300, depending on what mufflers you use.
 

Rusty Nail

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is that rebar that was being used as the hanger?

Hands down my favorite part. I vote to keep the rebar hanger, I am considering adding some to my exhaust - because that is cool, dude!

I would pick a different exhaust shop. That is easily DOUBLE what it would cost me. (At least!)

IMO 2.25 ID pipe is well sufficient. Some would argue for 2inch..I only run aluminized pipe.
When I was younger, I also ran Flwmasters but they are loud! A super 44 is advertised as being loud? I don't think you will like it, plus they run a hundred bucks, each.
Each muffler adds 6 overall db. As I became more "mature" (ahem!) I began to lean for one muffler. Making two pipes from one outlet is not against emission laws? I don't know, but why would it be? Different shop.
Dynomax Super Turbo is my go-to muffler at age 40. They are EXCELLENT pieces. A tip will increase the volume, and shortening the length of pipe will also.
Maybe a Dynomax # 17747 is a good choice. The 20 inch muffler will have considerably more packing material and yield a smoother note. (the boat rumble)
If you end up with one outlet, you may WANT a tip and can add later.

100 bucks for the stick of pipe.

60 bucks for a cat

- dynomax makes great ones!
http://www.jegs.com/i/Dynomax/289/1...9D9idj_7Tu_svZxtfGVvio5OcmDWRo8KDORoCcsvw_wcB

70 bucks for the muffler

http://www.jegs.com/i/Dynomax/289/1...jlnRU2FwJaLL2IguxxEUd6eW3N8jyXgE0ERoCDi7w_wcB


$230+ labor puts me at $300.

I aim to run a Dynomax 17553 Ultra Flo X when I dual exhaust the Blazer. Good luck!

www.dynomax.com
 
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Georgeb

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smoothandlow84

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I would certainly say it needs replaced! Lol....probably sounds loud. Definately go with an aluminized setup to eliminate the rust through.
 

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I am in close to similar situation. And yours should currently be single 3" pipe after y-pipe. I am tryung to find a system that would lower in noise compared to current set up. Search craigslist for stock late model truck exhaust for muffler/cat and then bring it to a shop to put it all together. Or the walker route.
 

Georgeb

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I am in close to similar situation. And yours should currently be single 3" pipe after y-pipe. I am tryung to find a system that would lower in noise compared to current set up. Search craigslist for stock late model truck exhaust for muffler/cat and then bring it to a shop to put it all together. Or the walker route.

The problem with the late model exhaust idea is right side vs left side exit.
 

adamj

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Thanks for talking some sense into me, I think I'm going to put together my own system instead of going to a shop, especially since I'm just replacing the stock setup and not going with a system that needs more fabrication involved.

I'm sticking with the 3" stock single exhaust style, that's what I have now.
You guys are correct, it becomes 3" back after y-pipe.

I might need some hangers welded on since I'm not sure what parts will come with them already. The hangers I'm seeing are 1) tailpipe after axle 2) tailpipe before axle 3) pipe between muffler and cat. Is there another one further up that I'm missing?
Other than that, should I be able to clamp muffler to tailpipe, muffler to cat, and cat to y-pipe? Even though they say 3", are the tailpipe/muffler/cat/y-pipe designed to be setup as slip joints over each other?

Here are the parts I've selected:
Tailpipe: Walker 45424 ($63)
Muffler: Walker 18228 ($50) or nicer = Dynomax Super Turbo 17769 ($90)
Cat: Walker 15693 or MagnaFlow 93476 ($150)
Clamps (x3 clamps for 3" pipe) = $15

Still unsure about Y-pipe and if I should replace that too with Walker 40317.
 

Georgeb

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I believe you want the 35362 brackets for hanging the exhaust. I would keep your stick Y-pipe if it is still solid.
 

adamj

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2/3 hangers are good and I will try to reuse them. The 3rd rebar hanger I will see if the shop can re-weld it for me - I'd like to keep that as a memento from the original owner.
 

adamj

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Parts are on the way! I got band clamps to seal the lap joints. I took another look at the current exhaust and I believe the drooping Y-pipe is related to that broken rebar hanger. I'm going to try and find a stock hanger in a jy and see if I can clamp that on. I want to see how tight it pulls it up - I'm wondering if that did any damage/warping of the pipe/exhaust manifolds by having all that weight hanging from the manifolds.
 

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