MBRP 18" Resonator on Kennedy 4" Exhaust [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: MBRP 18" Resonator on Kennedy 4" Exhaust


chuntag95
12-20-2004, 04:39 PM
I finally got the resonator installed on Saturday. I had a drone at 1600-1800 RPM. I did not put it all the way forward like was shown a while back as it looked too tight to me.:o I cut out about 14" in front of the bend right before the muffler. I had just enough room to get it on without taking down the whole exhaust. I had to pull off one hanger to get the movement back to get it in-between. Note: 8" Bi-Metal blade in an 18V Reciprocating Saw makes short work of cutting out a chunk :ro) , while a 6" blade will make you say words the offspring need not hear.Censored I used the stainless band clamps and all went well except busting my finger while tightening to the torque spec. Socket slipped off and finger is now black and blue :eek: . My 5 year old daughter was very sympathetic as she had smashed her finger in a door earlier in the day.
It definitely seems more quiet all the way around. Now I do have 2 sections where I have six 1/8"x3/4"x12" steel bar clamped around the pipe as discussed in another thread. I did try the system with just the resonator and it was better. I added the stiffeners or dampening weights or whatever you call them and I think it is a little quieter still. It is really hard to tell. I think I am back to around stock, but it has been sooooooooo long since I have heard a stock exhaust, I can't be sure ;). I did not cut the bars up and clamp them all the way around before adding the resonator. I was just adding weight, but the more I thought about it, the more I thought clamping all the way around would act as a dampener better. I originally left the bar in 4' lenghts and just clamped 3 of them along the pipe. I did not really do my changes in a way to specifically say x was this much improvement and y was this much or I would have cut the bars and clamped them before adding the resonator. I know the package is better for sure. So in summary, I have 2 one foot sections of six bars clamped to the pipe, followed by the Resonator, followed by the muffler followed by a resonator exhaust tip. I could add some more of the bars in a couple of places, but other than that, I am done with the quieting project.
Oh, and the resonator does hang maybe 1/2" below the frame rails. At least I think it does, but it is really close, so I'm not worried at all. The exhaust can easily flex that much if needed.
Chris

WillowCreekStable
12-20-2004, 04:51 PM
Have you compared EGT's before and after you installed the resonator?

chuntag95
12-20-2004, 09:16 PM
I have not done a bunch of romping on it, but "normal" driving there is no real difference.

sprintmod1
12-21-2004, 09:04 AM
Do you know the other thread where the dampeners are discussed??

MaxRock
12-21-2004, 01:08 PM
Oh come on Chris...you must be getting old! An exhaust that is too loud!!! :eek: It must be Censored when you start getting old!!! ):h

MaxRock

chuntag95
12-21-2004, 02:26 PM
SprintMod1 - Search for resonator and you should find it.

MaxRock - You got it, old and slow. Playing with speeds to find the best MPG, I found I could not run 63 or it gave me a headache. Now I can run any speed or RPM w/o issue. See, I haven't always got 21 mpg like you, so I have to work at it.

chuntag95
12-21-2004, 02:32 PM
SprintMod1 - http://dieselplace.com/forum/showthread.php?t=15251&page=3&pp=10&highlight=submarines

MaxRock
12-22-2004, 12:03 AM
Wow...headaches at 63 MPH!!! I have the Kennedy 4-5 exhaust and do get some drone at 1600 to 1800 RPMs, but nothing bad enough to give me a headache. I'm contemplating performing a mufflerectomy, but am concerned about the exhaust volume when towing my 5er! Just a point to ponder!

Mark

sprintmod1
12-22-2004, 09:52 AM
chuntag95,

Thanks for the info. I want to try something. Installed the MBRP system and on my truck it is making alot of noise in the 1500-1800 rpm range. It is real bad in the rear seats and for long trips (2-4-6-8 hours) it is irritating and headache producing quite quickly. A friend has a similar GMC and I rode in his quite a bit with his MBRP and it is nothing like mine.

Rockin
12-22-2004, 10:54 AM
I get a headache at 63 too. I think it is from my daughter beating me on the head for driving like a grandpa though ;)

chuntag95
12-22-2004, 11:30 AM
Definitely try the bar idea. I think it made a difference. I just got some zinc plated bar stock and SS hose clamps. I think cutting them in sections so they lay flat on the pipe works best. There are 2 components to it, first the bar changes how the pipe will vibrate due to stiffening it and second by changing the weight. If I had a welder, I would have done some tacking instead of the clamps and also used stainless.

Frank Blum
12-22-2004, 05:53 PM
These links might explain the difference better. Later! Frank

http://www.automotive.eaton.com/product/traction_stability/lockingdiff.html

http://www.traction.eaton.com/product.htm