I have lumpy cams and obnoxiously loud exhausts in two of my trucks..... Oh, and really glad you're back Greg! 
CK5
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'72 K5 - Greg's @MightAsWellK5 Build
- Thread starter Greg72
- Start date
This is the build description. I will improve this later. (GB)
I have lumpy cams and obnoxiously loud exhausts in two of my trucks..... Oh, and really glad you're back Greg!
So much of this truck build is a "sleeper" (or will be once the bodywork is reattached) that it doesn't make any sense to have a rowdy engine and exhaust that completely betrays that theme....
Imagine rolling up on this truck at some point (in the distant future) at a stoplight. Nice paint, bigger tires, stock-looking wheels and bodywork and a family cage....."Hmmm, seems like a pretty tasteful resto-mod" you might say. But there's kind of a deep, solid and steady rumble as the truck idles at the light. Maybe there IS a little more to the truck than you first noticed? Light turns green and you roll out side-by-side, except...that damn truck is gathering speed pretty damn FAST!!! In fact, that polite, deep rumble at the stoplight gives way to that unmistakable sound that can only be a big block Chevy at WOT!!!
"So long taillights........it was nice seeing ya!" 
More often than not, loud trucks are just slow noisemakers. Kind of like that drunk guy you always see at the bar wearing a TapOut shirt with the sleeves cut off. He makes a lot of noise and talks a good game, but nobody takes him seriously.
-G
I love the idea of the sleeper, that's the coolest, but I really think aside the idle loudness you may find it hard to pipe her down.. An aluminum headed bbc is gonna be loud because its output is very high(hp) and hp makes noise. I thought you meant you wanted sewing machine quiet.
No doubt.
I've only got about 12" of 3-inch exhaust pipe after the header collector, then whatever muffler I decide to use......then about 20 - 30" of additional tubing before it dumps out the side of the truck, probably in front of the rear tires unless I can find some miraculous routing that doesn't hit the rear suspension or fuel tank and allows me to get them all the way out the back.
At light throttle, I should be able to "tip-toe" around town and blend in pretty well with traffic..... but I suspect when this truck goes WOT, the sound is going to echo off the buildings and hillsides and probably set off a few car alarms too!!!
-G
Hahaha it's gonna sound awesome regardless. More bends reduces the output, even one DB is a huge reduction. Check out black widow mufflers, they're interesting, no baffles inside and they use the larger case for quieter sound. But it's almost like straight pipe sound cleaned up. Very crisp but not obnoxiously loud when cruising,no drone.
Muffler choice will be the biggest determining factor. I put a 3" system on a built bbc Camaro. He supplied a set of pypes mufflers. That car was obnoxious to say the least. I will say, avoid round mufflers, they don't help a lot in keeping things civil. And if you have the ability to put a x pipe in it will sound much more even and mellow.
I have a 1st generation bronco with a built roush 302. It makes a bunch of noise and sounds like it could do a wheelie. Then you stomp on it, makes a whole bunch of noise and that's about it. Lol.
Orginally I wanted the rowdy wtf is in that, but I've changed gears a bit and will be putting a LSA in my 72. It'll be a whiney little bastard, but I'm ok with that.
Nice to see you back at it, do we all need to get together and send you a helmet so we don't have to go without updates again?
I have a 1st generation bronco with a built roush 302. It makes a bunch of noise and sounds like it could do a wheelie. Then you stomp on it, makes a whole bunch of noise and that's about it. Lol.
Orginally I wanted the rowdy wtf is in that, but I've changed gears a bit and will be putting a LSA in my 72. It'll be a whiney little bastard, but I'm ok with that.
Nice to see you back at it, do we all need to get together and send you a helmet so we don't have to go without updates again?
Nah.....freak accident, and lesson learned.
Save your money for bacon and beer for BB2018.
-G
I'm going to have to agree with sreidmx.
When I first built my BBC, it was mild and I installed 3" exhaust with the MagnaFlow RV mufflers. It was still too loud. The neighbor wouldn't let me start at night.
When I first built my BBC, it was mild and I installed 3" exhaust with the MagnaFlow RV mufflers. It was still too loud. The neighbor wouldn't let me start at night.
No doubt.
I've only got about 12" of 3-inch exhaust pipe after the header collector, then whatever muffler I decide to use......then about 20 - 30" of additional tubing before it dumps out the side of the truck, probably in front of the rear tires unless I can find some miraculous routing that doesn't hit the rear suspension or fuel tank and allows me to get them all the way out the back.
At light throttle, I should be able to "tip-toe" around town and blend in pretty well with traffic..... but I suspect when this truck goes WOT, the sound is going to echo off the buildings and hillsides and probably set off a few car alarms too!!!
-G
I asked my local muffler shop about these flow masters. http://www.flowmastermufflers.com/?page_id=11167No doubt.
I've only got about 12" of 3-inch exhaust pipe after the header collector, then whatever muffler I decide to use......then about 20 - 30" of additional tubing before it dumps out the side of the truck, probably in front of the rear tires unless I can find some miraculous routing that doesn't hit the rear suspension or fuel tank and allows me to get them all the way out the back.
At light throttle, I should be able to "tip-toe" around town and blend in pretty well with traffic..... but I suspect when this truck goes WOT, the sound is going to echo off the buildings and hillsides and probably set off a few car alarms too!!!
-G
He said I wouldn't like them because they were to quite. I said, That will be prefect then.
I think there might even be quieter options in the Flowmaster lineup?
This was the space that I carved-out for the mufflers... and I was able to fit a 70-series in there (#52571) which is a pretty large can (22"L x 10"W x 5"H)...
-G
I'm with you on the quieter exhaust. Maybe it's an age thing. I used to love setting off car alarms in parking lots and revving the engine while going under overpasses, etc, but it got annoying that I would have to take my foot off the pedal just to hear what my passenger had to say. Loud is fun on occasion, quiet is wonderful the other 90% of the time. I'll go for the 90%.
I have used vortex cone inserts. Or it might have been their predecessors.
We built a thumping big block in a true sleeper car. A 78 Malibu 4 door.
To get it quite enough we used 2 mufflers and some cone inserts at the headers and the exhaust outlet. It was very quite. Until he hit the gas.
Obviously you don't have room for that. But you may consider the inserts. They don't do much for it by themselves but combined with a huge muffler ( more room for sound waves to dissipate) they make a difference at low engine speeds
We built a thumping big block in a true sleeper car. A 78 Malibu 4 door.
To get it quite enough we used 2 mufflers and some cone inserts at the headers and the exhaust outlet. It was very quite. Until he hit the gas.
Obviously you don't have room for that. But you may consider the inserts. They don't do much for it by themselves but combined with a huge muffler ( more room for sound waves to dissipate) they make a difference at low engine speeds
70 series are pretty damn quiet.. and fuggin huge too!!
You definitely have more room for mufflers than I envisioned. Those should flow enough for your big-block.I think there might even be quieter options in the Flowmaster lineup?
This was the space that I carved-out for the mufflers... and I was able to fit a 70-series in there (#52571) which is a pretty large can (22"L x 10"W x 5"H)...
-G
I'm actually really tired of how loud my 468 is.. It was ok before the ZZ454 heads and cam. Went up by something like a full point in compression and significantly more cam, now it's painful to drive with the windows open!!
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That's what I'm looking at ( Mostly due to no room for anything bigger ) How did it work out for you noise wise?
My new modified doors (cut down to match the bed rail height) don't even have window glass in them....
-G
I'm a long ways from needing mufflers. My build in over in 69-72 K-5. Right now I'm stalled out on rust repair.
