Restrictive Mufflers

-
bobscuda67

bobscuda67

Well-Known Member
Joined
Aug 27, 2005
Messages
2,106
Reaction score
387
Location
Michigan
I'm going to redo my exhaust system this winter and I'm taking my old stuff apart. I have Accurate pipes and mufflers on it now and want to replace the 2 1/4 pipe with 2 1/2 and new mufflers. Out of curiosity I cut an old muffler apart and I was shock to see how restrictive it is inside. Although it ran well and sounded good.
 

Attachments

  • 008.jpg
    45.9 KB · Views: 2,174
  • 010.jpg
    44.3 KB · Views: 1,383
Yes, they are the stock 340 replacements from Accurate. But they did what they were supposed to do.
 
Bob, there are several that will do well but if you want 18" long bodies, like it came with, Magnaflow has some direct fit units. And, Goerlich sells some that flow slightly more. Goerlich XLERATORS are made with all USA components and they work very well. I can get you some numbers if you need them. Both of these are straight through and even the 3" ones are surprisingly docile until you romp on it. 2.5 ones are also nice sounding and flow more than you will likely ever need.
If you want some others, the VTs from Dynomax are unbelievably quiet at low throttle loads. We have some on a 410 Barracuda and you would not believe how quiet they are and how well they work. Even with a big thumping cam, the exhaust ring through the headers is louder than the exhaust out the back.
Tom
[email protected]
 
Here is the Xlerator internals. Under the st. st sleeve is a perforated core with just the right size perforation to control the sound level but still give it a good tone.
 

Attachments

  • XL shot1.jpg
    51.9 KB · Views: 1,259
For fun, here is a Dynomax Super Turbo. Walker makes a 14" body and a 20" one but not the 18" one that fits right on our A-bodies. 20" will fit but you need to play a few tricks with them.
 

Attachments

  • ST1.jpg
    41 KB · Views: 1,714
Hey thanks for the cut a way pics. I wonder if the Dynomax Super Turbo offset in center out would have about the same flow as the offset in and out. Not that it really matters with my mostly stock car.
 
The flow rate drops a few per cent. But since A-bodies need offset center, not much you can do if you want a good fit. The flow change is not as drastic as you would think and stock, or slightly modified engines, can't tell the difference.

Since the stock type mufflers flow in the 35 to 40% of a straight pipe range and the typical Super Turbos are in the 70% range, you can see why a per cent or two here and there will not be noticeable.

Tom
 
Somebody could make a "S" shaped muffler. lol
 
A short muffler and an-shaped connector or tailpipes from non-stock plans.
Tom
 
What "we" used to love were the original turbo mufflers. Now I'm NOT referring to what everybody (including Thrush) might be CALLING a turbo, but rather the original, factory spec'd, such as Walker/ Maremont replacements for turboe'd Corvairs.

The problem with the originals is the size of the fittings in some cases, but the really BIG problem is the pollution nowadays "everybody makes a turbo" so nobody knows what one really IS (was)
 
You are right 273. The original ones have a neat sound but they have sort of an oddball size. I have two of them downstairs and they have a unique sound. Not too loud or quiet and they have good flow numbers too.
Tom
 
We tested some of them and unfortunately, they were loud and had a different sound to them. In fact, they were as loud as the similar sized Flowmasters but they did pass more air and ran better on the test vehicles we used. They also resonated BUT they were smaller case ones and that is typical of most small mufflers. When you see what the exhaust gases have to do to get through them, you see why the air flow values we measured were less than optimum.
HOWEVER, so you do not think all is negative about them, they make them in all sorts of configurations so you can make them fit anything. Plus, they made some squatty ones with oval inlets and outlets for really low cars.
Tom
 
Who makes a nice 2 1/2" exhaust for our A bodies? I want to do this right the first time, but I want it to look close to stock.
 
How old were those Accurate mufflers?? I have been told there are a different style with newer vs. older mufflers. I bought mine in 2000 and they look like your cutaway mufflers when I cut mine open too. I replaced those Accurate mufflers with a pair of DynoMax Super Turbo mufflers. With NO other changes, my GTS ran a full second faster in the 1/4 mile and picked up almost 4 MPH! I have since replaced the Accurate 2 1/4" system with a TTi 2 1/2" system X pipe with Ultra Flo mufflers. That was worth another .2 in the ET and 1 1/2 mph.
 
Just wondering...any suggestions for a turbo build? From what I have read chamber mufflers are not very desirable....
 
What's the rest of your setup and plans for the future? Full 2.5" exhaust with manifolds requires custom-bent downpipes or ones from TTI (also included in full system). If you are planning on putting full-length headers on anytime soon I would hold off on doing the exhaust until you get them and do the entire system front-to-back at once.

Hey VOETOM have you flow tested one of these by any chance?
3.jpg

http://www.classicchambered.com/index.html

I have a pair of the longest 2.5" "powersticks" on my '70 Duster and I love the sound, about as raw as it can get...
 
Mope, we have not but I bet they pass a lot of air through them since there are not many restrictions. If they have 2.5" center tubes, they will work well. I have heard some chambered Camaros and man, even stock, they are loud!!!
Tom
 
You must log in or register to reply here.
-

Back
Top