Flowmaster Outlaw muffler - anti-reversion?

[David Vizard]

I am going to post my experiences here under new thread entitled "Of Flowmasters and Super Traps"

DV

[EDC]

Hey Ed, it's been a while; good to know you're still/again with us!

Well - you may "soon" find out why I don't come here very much Bill...

[David Vizard]

As shown in the cut-away image, from top to bottom (flow goes w/ the angle of the fins/rings, not against).

I think that is pretty cool. Never seen that. I would definitely say that is a AR device.
Ho well does it knock down noise?

If you want your neighbors to hate you install a pair of these!!

DV

[exhausted]

As shown in the cut-away image, from top to bottom (flow goes w/ the angle of the fins/rings, not against).

I think that is pretty cool. Never seen that. I would definitely say that is a AR device.
Ho well does it knock down noise?

If you want your neighbors to hate you install a pair of these!!

DV

I would bet they do not attenuate noise very well. Web site says they are for those race cars that are required to have mufflers but no rules as to how they are made or decibel standards.
Ha, I have already called some of my customers that might try them and see how much AR effect.

[Mikej26]

I wonder if they’d work well at the end of a full exhaust in place of a resonator

[BradH]

I would bet they do not attenuate noise very well. Web site says they are for those race cars that are required to have mufflers but no rules as to how they are made or decibel standards.
Ha, I have already called some of my customers that might try them and see how much AR effect.

I'm going to contact the company that makes the X-pipe system on my car (TTI) and ask about buying only the parts between the collector reducer and the X-pipe connection. I'd like to try the as-is setup against that same section reconfigured w/ the 7"-case version right after the reducer.

Does the addition of an AR device into the exhaust system typically have an impact on the optimum tune used prior to incorporating the AR feature? If so, any particular trends to look out for, such as needing to change the low-speed carb circuits in some manner that is "happier" after AR is added?

[BradH]

As shown in the cut-away image, from top to bottom (flow goes w/ the angle of the fins/rings, not against).

I think that is pretty cool. Never seen that. I would definitely say that is a AR device.
Ho well does it knock down noise?

If you want your neighbors to hate you install a pair of these!!

DV

My neighbors -- at least some of them -- already hate me. They think I sold "the loud car", not realizing the one I'm still putting back together that they've never seen run makes "the loud car" sound like a Prius.

I wasn't expecting any noise reduction w/ the addition of something like I've shown above, since the car has mufflers that handle that reasonably well. This is a pure anti-reversion investigation on my part.

[David Vizard]

Brad, you posted :- I wasn't expecting any noise reduction w/ the addition of something like I've shown above, since the car has mufflers that handle that reasonably well. This is a pure anti-reversion investigation on my part.

Any AR effect as far away from the port/valve as you seem to indicate will usually have a very low AR effect. May I suggest you focus on an AR device located at the exhausts interface with the heads.

If you are interested I can post a drawing of something that worked well on the dyno by making a lot more torque at low rpm along with about 10 lbs/ft extra peak torque over a well sorted conventional style header. Peak power also took a marginal step upwards.

AS an aside raw emissions were also reduced as well as the noise.

Let me know what you want to do here.

DV

[exhausted]

Bottom line, David Vizard is correct in stating a AR device has more effect when implemented closer to the engine. I would disagree with placing them at the head/header interface as commonly seen but that is a different subject.

A long while back I was able to build a single tailpipe setup on one of Dale Earnhardt's race trucks.It made more bottom end power that they were not ready for and were worried about the tune so they never pursued further testing as they couldn't run them on the dyno. But I have pursued it over the years.

I have done extensive testing with single tailpipes on several different types of race cars. Just going from dual pipes to a single pipe will extend the rpm range down with more bottom end power without hurting top end power. Back to back testing at the race track results in faster lap times.

Adding AR chambers in the tailpipe after the final merge collector will add additional bottom end power without hurting the top end power and again show in lap times. I have seen AR chambers at the collector on each bank and another in the tailpipe.

The effect on even 410 sprint cars is dramatic and won't say more on that.

I suspect there are not a few efforts that are experimenting with AR devices.

The Magnaflow "mufflers" they sell are AR chambers and available in several sizes. They were originally developed by Hendren Engines here in NC. They sold the production rights to Magnaflow, not sure about the patents. They can be very effective and I've been playing with them for over 5 years. I wish there were more sizes available.

I think we will see an increasing amount of development in the future as I am convinced from what I have seen that although Jim Feuling was the pioneer in AR chambers there are a lot of ways to skin this cat and the effect they have both in the headers directly and in the entire system can not be denied and will result in changes to other components further inside the engine along with changes in understanding of exhaust systems.

[GARY C]

Yes, Brzezinski Racing Products talks about a 29 hp gain with a 2 into 1 system over duel 3".
https://www.castheads.com/manifolds-car ... r-systems/

[BradH]

DV - I've seen recent examples of AR chambers integrated into each primary pipe of a header, where the chamber appears to be from 4" to 8" after where the header flange meets the heads. I'm using off-the-shelf 2" x 3.5" headers on my car, but they're definitely of the "designed to fit, rather than designed to perform" ilk.

If I was willing to carve up another set (this particular model does fit my car & raised-exhaust-port head combination decently), I suspect the way to add this feature would be to reduce the primary diameter right off the head from 2" to either 1-3/4" or 1-7/8", and have the smaller tube extend into the 2" section well past the visible weld where they'd join.

/////////////////////////////////////////////

Just for "fun", I cut-n-pasted images of my style of header w/ a 3.0" reducer connected to a shortened cut-away view of the subject Flowmaster "muffler". It wouldn't be the first Frankenstein component my car has had...

[BradH]

The Magnaflow "mufflers" they sell are AR chambers and available in several sizes. They were originally developed by Hendren Engines here in NC. They sold the production rights to Magnaflow, not sure about the patents. They can be very effective and I've been playing with them for over 5 years. I wish there were more sizes available.

Could these be the Dynatech "Torque Boosters" you're talking about? I've seen some reference to those having been designed by Hendren, which is why I ask.

[exhausted]

The Magnaflow "mufflers" they sell are AR chambers and available in several sizes. They were originally developed by Hendren Engines here in NC. They sold the production rights to Magnaflow, not sure about the patents. They can be very effective and I've been playing with them for over 5 years. I wish there were more sizes available.

Could these be the Dynatech "Torque Boosters" you're talking about? I've seen some reference to those having been designed by Hendren, which is why I ask.

Ok, I just realized I have forgotten who actually is making them. Sorry. I have magnaflow on my mind. I do quite a few hot rods and restomods and use the Magnaflow XL chambered mufflers in SS. They are not too expensive, the "turbo" style construction and size availability and sound are just right for street cars, and you can get them in a 20inch case as well as the "normal" 14". Anyway, most times I can't remember what I had for breakfast,

[68post]

Yes, Brzezinski Racing Products talks about a 29 hp gain with a 2 into 1 system over duel 3".
https://www.castheads.com/manifolds-car ... r-systems/

His example is what I used in '97 on our all iron 2bbl street stock that did very well. Likely the only single exh on the track, with a less than 10" headpipe on drivers side. Too bad an AR muffler wasn't on board also. (we were still very loud !)

[Mikej26]

I believe these are the same as the Hendren.

https://www.dropbox.com/s/xsi61qy3da7d3 ... 1.jpg?dl=0