What type of exhaust does your 273 have??? show some photos!!!

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josuevalenza

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Trying to decide whether to go for 2, 2.5 or 3 inches, 1 or 2 mufflers, what make and model? and that sounds-performance better
 
IIRC according to accurate exhaust, the factory style single HP system flows better than a dual exhaust.
 
I have the Accurite system. It isn't cheap but it fit perfect and sounds and preforms great.
 
What are you driving? If you have a 67 Barracuda, you'll have a hell of a time getting a second pipe over the axle any larger than 2 inches. My exhaust guy thought he could run 2.5", but it bangs against the spring when cornering, and has zero clearance on the tank side.

When they say the single exhaust flows better, that's with that huge "Formula S" resonator, which costs as much as a whole exhaust system itself.
 
61532729411__846C2D2B-C288-4B1A-8ACE-22A892A8337F.jpeg
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Doug’s headers, TTI 2.5” with Xpipe.
 
josuevalenza said:
??? Wich one is it???





Any Muffler or just a straight pipe?
Click to expand...
It is considered a "Hemi style low restriction muffler". You really need to get on their site and see for yourself.
 
My 67 Dart 270, 273-2 bbl has the origi
nal single exhaust that it left the factory with. I'm not going to touch it until it starts going to hell. It's nice and quiet!
 
340 exhaust manifolds, Tti 2.5” head pipes, Summit Racing 2.5” header back kit and dynomax ultra flos. Sounds awesome to me, not too loud at 70mph ~3200 rpm with the 3.91’s. I don’t have any real revving on video but here is the cold start.



And warm idle



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Just so you know,
back in ~1999, I bought a set of Nickle-plated TTI headers for my 68 Barracuda/367/4-speed/3.55s, and their full length dual 3"exhaust; which, fit like a glove. Yeah it was tight, but it fit. IIRC, I paid a lil under $1000 for the system.
For the install; I started at the back, and all joints are slip fit. The TTI clamps are just suspending the system.
Eventually, I installed a couple of sheet-metal screws to index the TPs to the mufflers, cuz the TPs had a tendency to rotate. The 3-pass Dyno-max mufflers are hung from the rear seat-belt bolts, straight down..Honestly, the install was a breeze, on the 68.
A couple of years later, I moved my springs over with the 1/2 kit, and narrowed my rearend. That didn't seem to affect it at all.
Just so you know.

But to install a GVod, I had to cut out the "H". The engine immediately lost bottom-end torque and I really noticed it. But I loved the new sound. My solution was to replace the standard 2.66-low Mopar box, with a 3.09 Commando box. Problem solved.
If I had had a smaller engine; IMO, that would not have been enough. I would have re-installed the H, a lil further down the line.

EDIT
But yeah;
> dual 3" would be overkill for a 273.
> I'd still run it.
> it's heavy. IIRC about 75 pounds from the headers back.
Is it loud? Only at WOT.
Is it annoying? Only to the neighbors, if I roll in late at night.
Does it drone? IDK; Not at 65= 2240rpm. I can't recall from before the GVod, but one would think, I'd remember if it did.
Yes, for the most part she has run the 3.55s since 1999, with brief stints of just about everything else.
My stock long-block lo-compression 318 4V loves the dual 3s, and sounds real good with it, too.

Funny story
Some here on FABO have the impression that I am a 318 hater.
That ain't true.
I just like annihilating tires with my 367.
I used to run a 318-4v every winter. and I would run various transmissions behind it, before introducing them to the summer motor, the 367.
One winter
I was running the Mopar A833 with the GVod behind it, and it was set up for gear-splitting. This provided Seven progressive very close ratios, with a double overdrive. I ran 2.76s for a while, in the back. The carb was a big Thermoquad, on a small-port intake.
SO
What I liked to do, was to rip thru the gears at low rpm, and let that big TQ roar. I mean this was a 150 hp engine, so puling something like, 2200 to 2800, it takes about 17 minutes to hit 65 mph , roaring the whole way.
I loved it.
With that combo, 65 was 2240rpm in double od, lol . With the 3.09 low in the trans, 2.76s takes off like 3.23s with the standard 2.66 box. Eventually, I tried this with up to 4.30s, which cruised at 65=1840 in double-od, and takes off like it has race gears.
Here's the point,
for a streeter, gears makes or breaks the combo, and since I loved the roaring TQ on a 318, for winter; I would love to try it on a 273.
I know pretty much exactly how I would build that combo.

Now, I know you want to keep your car more or less a tribute car, so the above may just be anecdotal, but, if the 273 gets to feeling a lil sluggish down the road, I got an automatic story I can relate, too. I swapped these engines around every spring and every fall 5 or 6 years in a row, so there's almost no combo I haven't tried.......... and you know, a 273 is only a small-bore 318............
 
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AJ/FormS said:
Just so you know,
back in ~1999, I bought a set of Nickle-plated TTI headers for my 68 Barracuda/367/4-speed/3.55s, and their full length dual 3"exhaust; which, fit like a glove. Yeah it was tight, but it fit. IIRC, I paid a lil under $1000 for the system.
For the install; I started at the back, and all joints are slip fit. The TTI clamps are just suspending the system.
Eventually, I installed a couple of sheet-metal screws to index the TPs to the mufflers, cuz the TPs had a tendency to rotate. The 3-pass Dyno-max mufflers are hung from the rear seat-belt bolts, straight down..Honestly, the install was a breeze, on the 68.
A couple of years later, I moved my springs over with the 1/2 kit, and narrowed my rearend. That didn't seem to affect it at all.
Just so you know.

But to install a GVod, I had to cut out the "H". The engine immediately lost bottom-end torque and I really noticed it. But I loved the new sound. My solution was to replace the standard 2.66-low Mopar box, with a 3.09 Commando box. Problem solved.
If I had had a smaller engine; IMO, that would not have been enough. I would have re-installed the H, a lil further down the line.

EDIT
But yeah;
> dual 3" would be overkill for a 273.
> I'd still run it.
> it's heavy. IIRC about 75 pounds from the headers back.
Is it loud? Only at WOT.
Is it annoying? Only to the neighbors, if I roll in late at night.
Does it drone? IDK; Not at 65= 2240rpm. I can't recall from before the GVod, but one would think, I'd remember if it did.
Yes, for the most part she has run the 3.55s since 1999, with brief stints of just about everything else.
My stock long-block lo-compression 318 4V loves the dual 3s, and sounds real good with it, too.

Funny story
Some here on FABO have the impression that I am a 318 hater.
That ain't true.
I just like annihilating tires with my 367.
I used to run a 318-4v every winter. and I would run various transmissions behind it, before introducing them to the summer motor, the 367.
One winter
I was running the Mopar A833 with the GVod behind it, and it was set up for gear-splitting. This provided Seven progressive very close ratios, with a double overdrive. I ran 2.76s for a while, in the back. The carb was a big Thermoquad, on a small-port intake.
SO
What I liked to do, was to rip thru the gears at low rpm, and let that big TQ roar. I mean this was a 150 hp engine, so puling something like, 2200 to 2800, it takes about 17 minutes to hit 65 mph , roaring the whole way.
I loved it.
With that combo, 65 was 2240rpm in double od, lol . With the 3.09 low in the trans, 2.76s takes off like 3.23s with the standard 2.66 box. Eventually, I tried this with up to 4.30s, which cruised at 65=1840 in double-od, and takes off like it has race gears.
Here's the point,
for a streeter, gears makes or breaks the combo, and since I loved the roaring TQ on a 318, for winter; I would love to try it on a 273.
I know pretty much exactly how I would build that combo.

Now, I know you want to keep your car more or less a tribute car, so the above may just be anecdotal, but, if the 273 gets to feeling a lil sluggish down the road, I got an automatic story I can relate, too. I swapped these engines around every spring and every fall 5 or 6 years in a row, so there's almost no combo I haven't tried.......... and you know, a 273 is only a small-bore 318............
Click to expand...
so…. At the end, stock header, 2.5 H pipe, 2 super turbo dynomax 17733, 2.5 end pipe.

This would give me great growl and a vintage muscle car feeling??
 
I had a simple 2 1/4" dual exhaust with the 273 and factory manifolds in our 67 cuda. Sounded awesome.
Recently installed a 340, and went with 2 1/2" TTI head pipes and 2 1/2" Summit kit from headpipes back. Sounds great, deeper tone than previous setup. The 2 1/2" is tight, I wouldnt recommend a 3" setup unless it's absolutely required and installed by a professional. I'll get a current soundbite.
 
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No pics and not yet installed to my 65 Dart wagon, I went with Waldron’s Charger 273 (AKA the Commando) exhaust. It’s got the same size measurements that Toolmanmike posted and has basically a straight through muffler with one end flattened like an original for clearance.
 
I was worried about a single output system on my '66 but the Accurate Exhaust HiPo system (Y pipe is made more like a header collector) fits and sounds way cool to me. It just growls when you get on it.
 
josuevalenza said:
so…. At the end, stock header, 2.5 H pipe, 2 super turbo dynomax 17733, 2.5 end pipe.

This would give me great growl and a vintage muscle car feeling??
Click to expand...
You didn't mention the application. What year and model are you working with?
 
josuevalenza said:
66 Dart V8 273 - 4 speed mec
Click to expand...
Ah sorry. I didn't remember you from your other thread. The most correct system you can buy is the Accurate HP single system. Something to know if you are thinking about a dual pipe system, the transmission crossmember is designed for a single pipe on the drivers side. The crossmember can be modified to accept a right side pipe or a custom bent pipe can go below the crossmember. Not the neatest install but the only way to do it.
Dual Exhaust Crossmember Modification on 64-66 A-Bodies?
 
Uncle Tony recently said that single exhaust is just as good as dual (or sumtin like that) on a 65 Barracuda junker he was touting on YT.
 
josuevalenza said:
so…. At the end, stock header, 2.5 H pipe, 2 super turbo dynomax 17733, 2.5 end pipe.

This would give me great growl and a vintage muscle car feeling??
Click to expand...


Headers can produce a unique sound at both ends; yes. and the more "performance-built" the engine is, the more it sounds like a muscle car.
But a stock-cammed 273/318, thru log-manifolds, and especially a lo-compression one, I'm gonna say, um, no, you wouldn't get a "vintage muscle-car feeling" ; at least not at low rpms.

Here is my experience with the above scenario, albeit with a 318

The cam in your engine has the same/similar specs as has the 318, namely, it is a "short-Period" cam, with a loooog period power stroke, about 118 degrees. compared to a race cam of less than 100, and a typical street cam around 106/108.
If you want a growl in such an engine, with a long powerstroke cam, like as is the 273cam, put small pipes on it to keep the energy up, so the still hot, supposed to be still expanding exhaust gasses, can "pop" when they hit atmosphere. Otherwise it's gonna sound, IMO, I wanna say, like crap.
Most of the sound that the hi compression 340s made, came from the high-energy exhaust, chugging down the 2.25 pipes and popping modestly, at the outlet; which pop, was shaped by the rectangular tips. Take any one element away, and IMO, the sound went away.
IMO, yur never gonna get that "feeling" that you are looking for, with a lo-compression, stock-cammed, 273/318, thru dual exhaust; as there is just not enough energy left by the time it gets to the rear bumper ... unless maybe you wrapped the pipes, lol. The energy has to stay in the gasses. If they give up their heat to the cylinder-walls thru a long power stroke, and to individual header-pipes, and to large-diameter exhaust pipes, and to 3-pass mufflers, then by the time they get to the end of a 2.5" tail-pipe, you practically gotta suck them them outta there, especially at idle.
Every chamberfull of burnt gasses starts out, occupying a volume of 1/8 of the engine's displacement, plus the chamber, which for a 273 is about 642cc at 8/1 Scr. At idle, by the time that slug gets some 12ft to the bumper, it has given most of it's heat away on the trip, so it staggers out the end and falls to the ground, which in a dual exhaust system, is followed by three others, staggering into the world.

The point is that no matter how you tune the 273 dual exhaust, it will never sound like a performance engine, until you build it into a performance engine. and even then, you gotta deal with the tiny amount of exhaust trickling out the ends.
But you know, some guys say that the original hi-po 273 2-into-1 had a distinctive sound. IDK; I never heard one; in 66 I was only 13. I never even saw an early Barracuda until some 10 years later.
Here's what I know, if you try to jam your 273 exhaust down a small enough pipe to make it sound like a performance engine, then it's gonna lose power as it revs up, compared to a free-flowing exhaust. Bad sacrifice in my opinion.
So what do you do?
IDK, but
I can tell you what I would do if I had a lo-compression 273; If I was looking for sound; notta chance would I back that thing out my garage at 8/1 Scr and expect it to sound like a vintage muscle car. What I'd probably do is keep the original single exhaust and put a glasspack on it.
But you know, before that, I would try it with a length of straight pipe taking the place of the muffler, cuz I know you want to too, lol. and, I would try a rectangular, no baloney-slash, exhaust tip. Badaboom!
Now, if you put a hot cam in there with a hot compression ratio, that would be a whole 'nuther conversation.
But I gotta tell ya, notta chance would my 273 stay at 8/1, unless it gets supercharged.
 
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