Dual Mode Mufflers !!! YES

[warren]

Finally after looking into the DM Mufflers last yr. I got mine from Dennis R. a few days ago and they go in tomorrow along with an X pipe.

Spoke to the factory engiineer again and learned some new stuff. Factoid.
They do produce lots more HP and TQ. They are unique and built in their lab by hand. They are a bargin.

Because they produce more back pressure until the flaps open they produce
more TQ on the low end. They open at 3 psi. 2500-3000 rpm. or so.

Care should be taken If installing with orig. 2 1/4" pipes not to slide the pipe
into the muffler 2 1/2" stub pipe more than 1" as there are small holes in the pipe beyond that.

He said the spring and flap door will last forever and they will go from a beautiful low rumble to a race car sound at WOT.

I went with a 2 1/4" X pipe to match origional and keep low end TQ.
The vibration dampners from the orig. mufflers will go on the new Duel Modes.

The same cross support to the rear of the H pipe will go in the same place
behind the X section again to keep vibration down so I can enjoy the sound.

This will add healthy TQ & HP. And ofcourse many thanks to Dennis for his
super expertise.

Warren
:beer:

[Smokie]

Cool, sounds like you did your research and should get great results. Let us know how you like them after install....a little video clip would be great.:beer:

[metroplex]

Now when you say your exhaust bearings are roasted, we will have to believe you.

Moving flaps/bearing surfaces have no place in exhaust systems, IMHO. My 1981 T-bird has an exhaust flap at the LH exhaust log for some stupid cold-start emissions system that is vacuum operated. It always makes a "squeeky" sound as it closes shut when the engine is shut down. I think the vacuum actuation helps it along. I wouldn't want to depend on the flap moving just based on exhaust flow though.


He said the spring and flap door will last forever and they will go from a beautiful low rumble to a race car sound at WOT.
Nothing lasts forever, especially spring metal exposed to moisture, heat, and combustion byproducts.

[oldekid]

Sounds like you're doing it the right way. I think you'll be very pleased with them. I am running the duals on my stock system and am very happy. I was a little disappointed until I changed out the tips with the delete tips. That made a pretty dramatic difference.

Have fun, and enjoy the rumble.

[Cobra25]

A friend of mine has them on his Marauder now for a while & love's them. Great sound, your going the love them.

[MENINBLK]

Please let us know how they sound, and if there is any drone
in the cabin while you are driving City and Highway !!!

[SergntMac]

Please consider before and after dynos? You seem excited about a remarkable increase in performance, and most of us are hopeful too. Some real world testing that back your factoid would be helpful.

[Cobra25]

Please let us know how they sound, and if there is any drone
in the cabin while you are driving City and Highway !!! I've driven my friends Marauder with those mufflers and their is no Drone at all on the highway and very little if any under normal driving.

[DEFYANT]

Now I am really excited.

I ordered mine two days ago. I am also considering the delete tips, but drone is a concern.

[Cobra25]

Now I am really excited.

I ordered mine two days ago. I am also considering the delete tips, but drone is a concern. Do the muffler's, save your money on Deleteing the tip's. Extend the stock tip's about 1 inch past the bumper, it keep's the inside a little quieter.

[DEFYANT]

Do the muffler's, save your money on Deleteing the tip's. Extend the stock tip's about 1 inch past the bumper, it keep's the inside a little quieter.
Man, you are reading my mind. My DM mufflers came today. Now I am waiting on DR's GP Kooks....and then the fun begins:D :banana2: :banana: :banana2: :banana: