/6 Exhaust: Dual or single? Your thoughts

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Deemo

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Just like the title says, I know it's not a big deal, but I have been thinking a lot about this. What do you think is best? Dual or single exhaust. I have a welder, a y pipe, lots of Pipe size choices, and use of a pipe bender. What size pipe is best for the /6s. I'm running the 170 for now to see what kind of trouble I can pull out of it. 27k miles all original.
 
I am putting together a slant six valiant wagon with a hotter than stock six but I am still using a single exhaust. To me, most six cylinder engines sound just awful through duals. A 2.5 inch single exhaust set up should be plenty and still sound healthy.
 
I want it to sound nasty. I've heard only one in person a few weeks ago and didn't have a chance to catch the guy but he was roasting firstGear
 
I've run headers and true duals. I liked it. If you want nasty, I think you'll want duals.
Back in the day, Dodge and Plymouth had a high performance single exhaust, which really sounded mean, but I think it was only a v8 option. It had a baloney sliced big rectangular attenuator. As big, or bigger than 70 Cuda tip. I don't know why nobody repops those, they were awesome. If they sounded that good behind a six, I would conside one of those.
 
I've run headers and true duals. I liked it. If you want nasty, I think you'll want duals.
Back in the day, Dodge and Plymouth had a high performance single exhaust, which really sounded mean, but I think it was only a v8 option. It had a baloney sliced big rectangular attenuator. As big, or bigger than 70 Cuda tip. I don't know why nobody repops those, they were awesome. If they sounded that good behind a six, I would conside one of those.
I'll look up the size on that. Seems a 2.25 2.5 in pipe is well agreed upon for the slants. Have plenty of that
 
If you are running dual headers, then the concenus over at slant6.org is to run a Y pipe into a 2.5 in single exhaust. If running true duals (like I will be doing), then run 2 inch pipes.
 
It really is up to you. Duals on a Slant not needed. I always looked at it as extra weight.Slants have a very unique sound. Photos are from my 64 Dart ,Clifford headers,Y pipe,2 1/2 pipes.

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IMG_1914.jpg
 
Looks good. I'll be getting a header this year sometime and working on finding an intake. Just want to make sure power and sound wise because I don't have extra money to do this twice. Two teenage girls are eating my wallet up and ones already begging for a 60s mopar:)
 
Dutra Duals, better than headers unless you're going racing. 2" pipe off of each of the two exhaust manifolds, into this wye connector, 2-1/4" pipe from there to this muffler. It's in Walker's QuietFlow SS premium OE line, all stainless steel (which is nice for durability), made for the '01 Jeep Cherokee 4.0 so it's easily got the flow capacity for a healthy 225 and it's tuned to keep an inline-6's exhaust from droning, has a 2¼" inlet and outlet (can easily step down to a 2" tailpipe). The inlet has a 2-bolt flange meant to bolt directly to the outlet of the Jeep's catalytic converter, but there's plenty of length to the input pipe that the flange can just be sawed off in 5 seconds at the exhaust shop. It's got the 4¼" × 9¾" housing, muffler shell 20" long, so it'll be a bit of a tight fit in an A-body, but it will fit.

2" tailpipe with resonator. If I'm rich, I like a Flowmaster HP2 stainless unit with 2" in and out. It's 18" long, which is a workable fit behind most A-body quarter panels. If I'm broke, I like a Walker № 17198 4" round can-type unit, 2" in and 2" out, with offset outlet next to a proper hanger bracket.

Speaking of that, whatever muffler you wind up with, make sure to use very soft hangers. The hook-and-O-ring type, for example. Today's popular "rod and rubber box" type transmits a lot of noise to the passenger compartment.

(Tailspout outlet 45° or greater downward.)

I want it to sound nasty.

Loud exhausts tend to be fun for a week, then get old in a hurry. But if you're real sure you're not gonna get tired of it, then Dutra Duals, 2" pipes all the way back with no crosspipe, two of the muffler I link here in this post. It'll be edgy at all RPMs, and when you rev it up it will be very "rappy". Remember, the lower the volume flow through any given muffler, the louder it's going to be. So a muffler with three cylinders' worth of exhaust going through it is going to be louder than that same muffler with six cylinders' worth of exhaust going through it. 2" pipe instead of larger because you want to keep your exhaust velocity up -- not just for flow but for the loud sound you want.
 
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A 60s molar huh. U gonna pull it outta someone born in the 60s or do you know where you can get one already out lol jk jk. I have a 3" not starting from the header. Starts where the cat had started. Flow master. My car is idling a bit high right and is leaking a bit between intake and exhaust manifold now but it does sound wicked. I almost feel its to loud cause it doesn't have any power mods lol but I won't change it. I like it. I might be able to post a vid later. Can't wait to finish her up. Good luck on your exhaust. O and getting duals out the back would be easier than the 3" lol. I could have gone smaller and probably still been happy
 
Hahaha. Yeah I fixed the molar thing. Stupid autocorrect. And I see the 3 in being an issue. But I might go the magnaflow dual tip exhaust. But flip them upside down so the angle goes down and not up.

As for Dans post, loudness isn't an issue with me. I've had several v8s with cams and they never bothered me except my LeMans I had. The open headers killed me after an hour. I'll look that stuff up for sure. I'll post a video of before and after. But I've started the fun with 2.5 in pipe right out of the factory header.

I have some of the newer hangers I'm going to use and weld them up. They have the hangers then a rubber hanger then I'll weld those to the body where needed.
 
Just like the title says, I know it's not a big deal, but I have been thinking a lot about this. What do you think is best? Dual or single exhaust. I have a welder, a y pipe, lots of Pipe size choices, and use of a pipe bender. What size pipe is best for the /6s. I'm running the 170 for now to see what kind of trouble I can pull out of it. 27k miles all original.
Well, the very BEST is a header that goes 6 into 2 into 1, and the primary/system size would depend on the size, stroke, & application of the engine. In Your case, the 2.5" &
being stock is more than enough for the 170, sound is largely going to hinge on the choice of muffler. Duals are primarily desired for their appearance, which is fine if that
floats Your boat, but the single pipe of the correct size will out-perform them unless You use an "X" or "H" connector.
 
For many years now, my 70 challenger with the 225 SL-6, has been running very efficiently with the super 6 set-up, mopar elect. Ign. Orange box, high output coil, open element 14x3 K&N filter. As for exhaust system Hooker headers 3 into 1, 2.25 aluminized pipe, real duals w/"H" pipe crossover all the way to back of car, dual glasspacks and chrome cuda style tips under rear valance. As far as I'm concerned it sounds great and if pick up efficiency and or HP's along the way, so be it.
 
Just like the title says, I know it's not a big deal, but I have been thinking a lot about this. What do you think is best? Dual or single exhaust. I have a welder, a y pipe, lots of Pipe size choices, and use of a pipe bender. What size pipe is best for the /6s. I'm running the 170 for now to see what kind of trouble I can pull out of it. 27k miles all original.
i have dual hooker headers on my slantsix with 2 1/2 stainless exhaust and flowmasters. we love it.
 
Post #10 says it all. Whether you use headers with two collectors into one, or the Dutra duals with two into one, use the Flowmaster wye that Dan referred to and you will have a very nice system that a dual exhaust system cannot match the scavenging effects of.
 
I'm looking into that. Only thing I don't want is the bubbly sound that glass packs have. >.<. I like a good tone and smooth deceleration sound. YouTube offers nothing and nobody has one near me. It'll be done by the weekend. should sound good. Flow master sound is unique to that muffler, I may opt out for that one. Manga flow has nice tone but with me not being able to hear one, I'm probably going to go Flowmaster.
 
Then don't use glass packs. Use a good quality turbo muffler like the Walker Dynomax.
 
Are you thinking of the fat resonator on the 273 Commando Formula S Barracudas? They do repop those, for about $450. I think they fit a 2.25 pipe -- IIRC they were 2.5 back to the muffler, then 2.25 over the axle.

I've run headers and true duals. I liked it. If you want nasty, I think you'll want duals.
Back in the day, Dodge and Plymouth had a high performance single exhaust, which really sounded mean, but I think it was only a v8 option. It had a baloney sliced big rectangular attenuator. As big, or bigger than 70 Cuda tip. I don't know why nobody repops those, they were awesome. If they sounded that good behind a six, I would conside one of those.
 
I am going with a single chamber Flowmaster muffler. Like this: https://m.summitracing.com/parts/fl..._-flowmaster&gclid=CKP-gI-8pNMCFdgQgQod4lANzw

I've got 2.5 in pipe ready and going to make a complete exhaust from the header back. I'll have the measurements for all the pipe that you can pick up at the local parts house including hangers. If you can weld or have a buddy that welds, and don't want to spend 200 bucks at the local muffler shop, I'll be posting up the how to with everything.

My exhaust was done by a monkey with a welder. The welds are complete garbage and leaked all through out it. I'm taking the header flange off and re welding new pipe from that flange back and tucking the muffler up right before the rear axle. Then dumping it out right there with an angled tip. Going to try to hide it all under there. I do t want the tips coming out the back simply because I'm not going to bend five foot of pipe To go over the rear axle. I'm lazy sometimes but it should be fine.
 
Clifford headers
Clifford Y pipe
2.5" to the muffler
40 series Flowmaster
Turn down right off the muffler
Sounds like a pack of pissed off bumble bees.
 
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