Dynomax Race Bullets: COMPLETED

davekro · Mar 30, 2015

YellowBee said:
Should get a video of an ecoboost. Id be willing to do a video if you send me a pair

YellowBee,
For asking the question, I'd say you already have quite a pair! :lol: ;)

zackmd1 · Apr 2, 2015

So I have been thinking....

Catback setup!!! I am thinking about deleting the resonator and moving my race bullets into the location of the resonator. I will not be using a crossover just like the OEM resonator. Divorced duals seem to give the 3.7 a very unique sound and with the help of the correct muffler/resonator most of the unwanted raspiness can be removed. My hope is that I will keep the overall exhaust note of my axle backs! Just make it a louder/deeper and lighter weight setup. Looking to do the modifications by the end of this month/ early next!

FireHive · Apr 2, 2015

Very interesting. Moving the mufflers to the middle should also further reduce drone ( i know you fixed that a while ago with dem engineering skillz). I also predict a deeper exhaust note for some reason.

EDIT: a little unrelated, but can anyone predict what a twin x pipe, like Corsa is doing for their catback system for the GT, will sound like with the V6? The twin x pipe makes the Corsa the best sounding exhaust for this gen so far IMO.

Rv-Junke · Apr 6, 2015

zackmd1 said:
For the sake of not creating another new thread I am updating this one with my new exhaust. The details of my exhaust are below. There was a sizable amount of drone at 2k which I have since solved without effecting back pressure or changing mufflers. I created a resonator tube between the muffler and the exhaust tip that tuned to the right length created a sound wave to cancel out my 2k drone. It's called a 1/4 wave resonator tube or a Helmholtz resonator. Using a few equations from physics II and some assumptions on the speed of sound at operating temp I determined the length of tubing needed for each muffler. As you can see in the pictures below I managed to fit 33" of tubing within the stock muffler location. A bill of materials is attached below as well. Completed my system cost $355.98.

Videos!

Please listen with headphones!

Exterior:

Interior:

RIGHT on! Nice work....

JWS · Apr 6, 2015

Exhaust Tubing

zackmd1 said:
Overall noise is only a mild increase over the stock exhaust. I would describe it as a more aggressive stock exhaust note. As long as the resonator tube is the right length someone could mistake my exhaust for the stock exhaust at highway speeds.

I guess you could say you have a REAL trumpet exhaust!

(Or would that be TUBA or Trombone?)

maximized98 · Apr 23, 2015

Ok so I purchased this setup from Zack and I am very pleased. My first reaction after I turned on the car was wow. The installer also said very nice. Both of us was not expecting a deep tone on a v6. We were both wrong. I am going to upload a video later today.

I have a convertible so I was very nervous about this exhaust. As designed, after 2k the drone and most of the sound goes bye bye. Overall I am very happy. The exhaust is kind of loud around the 1600-1900 rpm range.

There is alot more torque that is for sure. I was cruising at 80mph and i mashed the gas, good god!!!

Here is a video. Just used my cell phone so be nice

The top was up

Kipperman · Apr 23, 2015

@maximized98 did you see an improvement in your 0-60?
also, any chance you could upload a video from outside the car?
thanks!:cheers:

maximized98 · Apr 23, 2015

Kipperman said:
@maximized98 did you see an improvement in your 0-60?
also, any chance you could upload a video from outside the car?
thanks!:cheers:

I have not done a 0-60 in my car since I have owned it. Do you want a simple revup with camera behind the car?

davekro · Apr 23, 2015

maximized98 said:
I have not done a 0-60 in my car since I have owned it. Do you want a simple revup with camera behind the car?

If you could do a video like this, that would be helpful. On mine, I wish i had slowed down on the return, so I could have been accelerating thru second and hit third at or not long after the camera. (As always, listen with Head Phones.)
[ame]

Idle and free revs only give a small piece of the sound picture, IMO.

maximized98 · Apr 23, 2015

I will do one of those on Saturday

zackmd1 · Apr 23, 2015

maximized98 said:
Ok so I purchased this setup from Zack and I am very pleased. My first reaction after I turned on the car was wow. The installer also said very nice. Both of us was not expecting a deep tone on a v6. We were both wrong. I am going to upload a video later today.

I have a convertible so I was very nervous about this exhaust. As designed, after 2k the drone and most of the sound goes bye bye. Overall I am very happy. The exhaust is kind of loud around the 1600-1900 rpm range.

There is alot more torque that is for sure. I was cruising at 80mph and i mashed the gas, good god!!!

Here is a video. Just used my cell phone so be nice The top was up

Thanks for posting up! Hope you continue to enjoy them! :thumbsup:

EvilRoosterJr · Apr 27, 2017

zackmd1 said:
Catback setup!!! I am thinking about deleting the resonator and moving my race bullets into the location of the resonator. I will not be using a crossover just like the OEM resonator. Divorced duals seem to give the 3.7 a very unique sound and with the help of the correct muffler/resonator most of the unwanted raspiness can be removed. My hope is that I will keep the overall exhaust note of my axle backs! Just make it a louder/deeper and lighter weight setup. Looking to do the modifications by the end of this month/ early next!

Did you ever end up doing this?

Dynomax Race Bullets: COMPLETED

davekro

Well-Known Member

zackmd1

Well-Known Member

FireHive

Well-Known Member

Rv-Junke

Rv-Junke

JWS

Well-Known Member

maximized98

Well-Known Member

Kipperman

Member

maximized98

Well-Known Member

davekro

Well-Known Member

maximized98

Well-Known Member

zackmd1

Well-Known Member

EvilRoosterJr

Active Member