So my 454 Suburban's exhaust is pretty rusted. I was thinking of cutting the entire thing out 4" from the cat converter with my sawzall. This saves me money since a shop would only have to fab up a new pipe & put a flowmaster on it.

But I wonder what it would sound like. Would it be really loud? If it sounded good I'd keep it that way. I don't drive it more then 1-2 times a week.

I've heard big block exhaust's at the track & they were obscenely loud. But those were race motors & not a well used 87 454 street motor.

Thoughts?

 

If the exhaust is going to be replaced anyway, why not?

 

You can always add a resonator afterwards if you think it is too loud.

 

its a 454 big block, Not a TL.


Depending on waht your looking for and muffler you chose you could get a sound you want. Not i dont think i would run 4" all the way. probably 2.5-3 tops.

 

I think he's saying he would cut it 4" from the cat, not have it be 4" in diameter.
...Oh, and it would be be obscenely loud. Throw a Flowmaster on there and you'll be good to go with a nice, live-able growl.

 

No resonator may make it the pop and backfire sound when letting off the throttle. Either way I'd put a Magnaflow on.

http://www.magnaflow.com/04sound/04trucks.asp

 

It would sound close to this:

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Do it

 

yeah that's a little loud there I'll still have the cat attached, so we'll see.
It's Saturday's project. I'll post a sound clip after i do it.

 

Id put a nice flowmaster or magnaflow on it

 

I had a Flowmaster Super 40 on my Yukon (5.3 Litre V8) and it sounded perfect......Nice loud Flowmaster grumble.......

 

It will be horribly loud, not to mention you will get exhaust intrusion into the car when its stopped and idling.

Much better off putting on an exhaust to the back, with the muffler of your choice. A resonator will only make it slightly less horribly loud.

 

I don't care a whole lot about interior noises. The thing is not anywhere near quiet inside as it is now. Remember it's a 87 Chevy. It's creeks, gowns, shutters, rattles, howls, etc.

 

No one makes resonators for a 454?

 

I'm a little confused. Is the exhaust going to empty out the rear of the vehicle, or below it? As Mirror mentioned, if if empties below the vehicle it won't sound pleasant. Especially with you inside as it resonates off the floorboards. If it was my vehicle I would replace the exhaust from the cat to the rear of truck. Use a standard muffler. From my understanding it's your tow vehicle, so why spend a substantial amount with anything fancy?


Terry

 

Not saying I will run it with or without an exhaust yet. Going to cut the pipe & go from there. It's already rusted & has holes in the piping. Just cutting myself to save $ on a new install.
It would dump under the truck. Around the 2nd row of seats.

 

it's going to be unbearably loud. my 1.8L civic was setup like that for about a week while a i saved up to get it fixed. I think I lost my hearing from that thing.

 

OP fuzzy could always try either side exiting pipes or full side exhausts- those should be easy to find for the big block Chebbie.

 

It's possible that it will not be as loug as you think. The muffler on my Pathfinder broke off and it was just a bit louder. It was a lot louder when the same thing happened to the I35. Nissan exhaust systems suck.

For me, I would go with something that's has a nice low growl to it as opposed to a loud sound.

 

The muffler on my wife's old I30t did the same thing around 85k miles.

 

It really ticked me off. And the part was really expensive. I actually had the flange removed and a piece welded in between both parts for the Infiniti because everything else was in great shape. If one of the parts break or rust, then I get a aftermarket cat back for it.

The Pathfinder was cheap.

 

I wasn't clear, sorry. I was talking more about exhaust fumes entering the cabin.

 

And again it's an 87 Chevy with TB injection. All I smell is gas fumes, & oil

 

And he constantly has a case of the munchies.

 

i would just have a stock style system run to the back of the truck. it might be a 454 but it is still a dog of an engine. i would keep it stock sounding as possible.

 

This. Take it to midas and tell 'em to make it cheap.

 

I cut the pipe today. Just after the cat converter. It doesn't sound like anything. There's a deep rumble at idle, but once I hit over 1K RPM, I get more of a gargle sound.
It's not very loud at all.
So either the cat is clogged or it really muffles the sound. The thing is a HUGE flat pancake. It's fine now until I get a system in place. I did notice a jump in power though. Pulls stronger now.

 

Here's a sound clip. It seemed to get a little louder & I think better after a little driving.
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cut the cat off. sell it to a muffler shop. get a stock exhaust put on. or do longtubes and it will make it sound 731% better.

 

It sounds sweet as it is.

 

My point is to not spend more if I don't have too. It's not worth it. I didn't buy it for that.