Exhaust single to dual on a tight budget - Then we get into some after issues

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SirRobyn0

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So I'm about to replace my exhaust systems. I like what I have quite a bit, but it's falling apart. Unfortunately I'm on a tight budget as I need to do rear brakes on the truck and bunch of front end work on the wife's minivan. So I need to replace it as cheaply as possible.

So what I currently have is the stock Y-pipe, running into a 3" cat, a 3"mid-pipe to a Walker FX muffler with dual outlets I think the outlets are 2" each. I've been very happy with this setup, but the cat and mid-pipe came to me used 4 or so years ago. The cat is obviously failing at this point, the mid pipe is paper thin, the muffler and tail pipes have holes. I cannot currently afford to replace this system with like products and as much as I tend to like good flowing single exhaust I'd like to switch it up and go to duals, just to see how I like it on the truck, but I have to make sure they aren't to loud or I'll hate it.

I'm going with an inexpensive dual kit Dynamax #89006, I can get it for $139 so it's affordable 2 1/4" dual pipes I can get it for $139. But there are a couple of things I do not like about this, there will be not an H-pipe or cats, but that's just for now. Once I get past Thanksgiving I should have money for a pair of high flow cats and later on I'll put an H-pipe in it. Dynamax kit should arrive on Monday.

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For mufflers I was going to do cheap Thrush turbos cost is $20 each. I've actually ordered and already received them, but I'm having second thoughts. I'm thinking of returning them and ordering a pair of Walker soundfx #17845, those are the OEM equivalent for dual exhaust. But they are $45 each. The thrush units are $40 total and the Walkers would be $90 each. Saving the $50 is appealing, but not if I'm gonna hate the cheapies. The walker is a 20" muffler body, where as the Thrush is 14".

So my first question, is anyone running thrush turbos in a dual setup on a SBC and want to give an opinion on how loud they are? Even better if you happen to have audio or video of your truck running with those mufflers.

Thanks.
 

CalSgt

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I ran 2.25” Hooker Super Comp Turbo mufflers, dual exhaust with no cats and side exit just past the rear tires on my square for 10 years and loved them.

Quieter than the average Flowmaster but still noticeably louder and deeper sounding than the stock v8 exhaust on the GMT400’s. I don’t recall them having any annoying drone either.

They were $20 each in 1997….

I even considered doing turbo mufflers for my frame off restoration but decided to do something different this time, hopefully I didn’t make a $250 mistake buying stainless Flowmaster Hushpowers.

Good luck Sir
 

SirRobyn0

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@CalSgt Thanks. Keep in mind with the pricing I'm getting is wholesale, so those $20 turbos I'm getting are $39 retail, still cheap by todays standards. If I can talk over the turbos and listen to the radio without the exhaust interfering I'll be happy.

I've heard some Flowmasters that I've liked and some I haven't, and I know pipe length, tail pipe length, where the exhaust exits, cats, ect it all effects the end sound, but in the end I don't want to spend the money for flowmasters cause I'd be 110% stuck with them. At least with the turbo's it's only a $40 risk.

And good luck to you to with the Flow's.
 

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The turbo mufflers will be fine they aren't that loud especially if you're not mashing the throttle and the pipes exit from under the truck. Just cruising you won't even notice them.
 

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I've ran the exact combo you speak of. It's really fairly quiet and not much louder than stock exhaust. Adding converters will tone it down a little further.

The Dynomax exhaust uses crush bends, unlike all the other kits, but should be fine with your 305.

What's your budget for each muffler? What specific sound do you desire? By the sounds (hah, I made a pun, lol) of it, you would want not too loud, but not too quiet and have a little bit of a rumble... but at the same time, you definitely want as little drone as possible. That combo tends to put you looking at the more expensive mufflers. The Hooker AeroChamber muffler is probably your best bet. I've ran those with the Dynomax exhaust on a 305 too and absolutely loved them for daily driver use. They sounded much better than turbo mufflers (with less drone too) and had a nice growl when you put your foot in it, yet were very tame when driving normally.
 

SirRobyn0

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The turbo mufflers will be fine they aren't that loud especially if you're not mashing the throttle and the pipes exit from under the truck. Just cruising you won't even notice them.
Thanks that's just what I wanted to hear, at least at this point I feel like it is worth while to try the turbos.
 

SirRobyn0

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I've ran the exact combo you speak of. It's really fairly quiet and not much louder than stock exhaust. Adding converters will tone it down a little further.

The Dynomax exhaust uses crush bends, unlike all the other kits, but should be fine with your 305.

What's your budget for each muffler? What specific sound do you desire? By the sounds (hah, I made a pun, lol) of it, you would want not too loud, but not too quiet and have a little bit of a rumble... but at the same time, you definitely want as little drone as possible. That combo tends to put you looking at the more expensive mufflers. The Hooker AeroChamber muffler is probably your best bet. I've ran those with the Dynomax exhaust on a 305 too and absolutely loved them for daily driver use. They sounded much better than turbo mufflers (with less drone too) and had a nice growl when you put your foot in it, yet were very tame when driving normally.
The crush bends are fine for the 305 and if I get 350 under the hood eventually it won't be wild so I'm not concerned with that, but is a worthy point for any future readers.

I don't mind if there is some exhaust noise when stepping into the gas, but normal driving I don't want it to be a distraction. Budget for the entire project is $0 since this was unplanned. Basically I need to keep it as cheap as possible, which is why the kit is attractive and the $20 a pop mufflers, I just don't want to throw $40 out the window a week later to change mufflers if the turbos prove to be to loud. I know the Walker SoundFX mufflers would produce a tone I'd be happy with so if I don't do the turbos, or I do them and are not happy with then that's what would be going on the truck, it's just that the mufflers are $45 each instead of $20. I know I'm nickel and dimeing this but front ends and brakes are simply more important. I suppose the answer is to try the turbos, just clamp them on and if I hate them, change them out for the walkers in a month or so after I get my next chunk of income from the farm. I can always hang on to the turbos for another use later on. Thanks for the prospective there.
 

SirRobyn0

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Nabbing an existing system from a salvage yard isn't an option Mr.Tight Budget? Those dudes keep stacks and piles of pipes layin around...only a thought for your consideration.
Not really any wrecking yards left in the area and the few that are charge so much it's ridiculous. I keep telling myself on one of my feed runs that I'll make a wrecking yard list. The last one where I went over to Richland would have been ideal, but at that point I'd almost have to stay overnight and that wasn't happening on this last trip.
 

SirRobyn0

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Ok, so I think at this point I'm going to go ahead and try the turbos and see how I feel about them.

The mufflers are here, but the pipe kit won't be here until Monday, so hopefully I'll be able to get going on this Monday later in the day or Tuesday. And I will let you all know how the install goes and what I think of it. I'll even shoot some video so ya'll can hear it too.
 

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Whenever we are in the Pick N Pull yard I am looking under trucks for fresh tubing and mufflers.
Super cheap to get stuff that way.

If you were closer, I would let you rummage my stock pile....
 

Bextreme04

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Ok, so I think at this point I'm going to go ahead and try the turbos and see how I feel about them.

The mufflers are here, but the pipe kit won't be here until Monday, so hopefully I'll be able to get going on this Monday later in the day or Tuesday. And I will let you all know how the install goes and what I think of it. I'll even shoot some video so ya'll can hear it too.
I had headers and dual 2.25" exhaust with some cheapo turbo mufflers on my 73 C20 with a 350 and they were very quiet. I ended up needing to do that because the exhaust that was on it when I bought it was completely rusted through.

Too quiet for me. My K20 now has dual 3" with Flowmaster big-block 50's on it(they were already on the truck when I bought it) and it is quite a bit deeper sound, but without any drone. It will be quite a bit quieter when I get the H-pipe on it, dual high flow cats, and run the exhaust all the way out the side instead of dumped over the axle. All of that is planned to happen this month before hunting season, except the cats that will go one when the EFI engine goes in.
 

SirRobyn0

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Whenever we are in the Pick N Pull yard I am looking under trucks for fresh tubing and mufflers.
Super cheap to get stuff that way.

If you were closer, I would let you rummage my stock pile....
I use to get down to Portland pretty frequently but not anymore....
I had headers and dual 2.25" exhaust with some cheapo turbo mufflers on my 73 C20 with a 350 and they were very quiet. I ended up needing to do that because the exhaust that was on it when I bought it was completely rusted through.

Too quiet for me. My K20 now has dual 3" with Flowmaster big-block 50's on it(they were already on the truck when I bought it) and it is quite a bit deeper sound, but without any drone. It will be quite a bit quieter when I get the H-pipe on it, dual high flow cats, and run the exhaust all the way out the side instead of dumped over the axle. All of that is planned to happen this month before hunting season, except the cats that will go one when the EFI engine goes in.
To quiet for you might be just right for me! We shall see, thanks for that info.
 

Ricko1966

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I had headers and dual 2.25" exhaust with some cheapo turbo mufflers on my 73 C20 with a 350 and they were very quiet. I ended up needing to do that because the exhaust that was on it when I bought it was completely rusted through.

Too quiet for me. My K20 now has dual 3" with Flowmaster big-block 50's on it(they were already on the truck when I bought it) and it is quite a bit deeper sound, but without any drone. It will be quite a bit quieter when I get the H-pipe on it, dual high flow cats, and run the exhaust all the way out the side instead of dumped over the axle. All of that is planned to happen this month before hunting season, except the cats that will go one when the EFI engine goes in.
Very similiar experience headers,cheap turbo mufflers turn downs ahead of the axle they are too quiet unless I'm standing on it.
 

SirRobyn0

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Ok so I'm just going to pull something in from another thread. When I did the transmission last year I was going to do the exhaust at the same time, because I knew it was getting to be time and it would be down anyway, but it didn't pan out in terms of time or money. So one of the concerns at the time was my dump bed pump and hose which is mounted inside of the frame rail on the passenger side.

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I think that the kit will put the muffler right next to the pump, which I think is pretty much the standard location for a muffler on one of these trucks. So one thing is that I will have to tilt the muffler some for clearance, and the other thing is I need to keep the heat from the muffler off the pump as best as possible, and I'll need to do something the keep the hose from melting down on the tailpipe. Here are my plans.

For the muffler I want to install one of these on the muffler.
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It's just one of those standard muffler shields that straps to the muffler with stainless steel clamps.

For the hose. The hose is a bit of a problem. It runs from the pump to the cylinder, which is located generally close to the end of the driveline. And it has to be able to move quite a bit when the bed is dumped. So there needs to be a pretty good safe are for the hose to be and move when the bed is dumped. My plan is to wrap the tailpipe from the muffler to where it turns up to go over the axle with header wrap. I have 50' of the cheap fiberglass wrap laying around at the shop. Because a tail pipe is much cooler than headers are I think this will be over kill, but I want to make sure my hose doesn't get melted down.

Anyone see a problem with this plan or have a suggestion let me know. Thanks.
 

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