SD2020
Member
This is a long story do I will compress it.
Rebuilt motor, MMX +30 NSR NTR cam. Hemifever tune. Mufflex 24”.
Caused severe resonance.
Little to no resonance before the new cam. It all started when I was testing the new tune, remote testing.
Put stock muffler on, still hurt my ears but they were and still are sensitive to whatever happened to them, so put the Diablo 87 tune back on it. Now the Diablo 87 tune with stock exhaust hurts my ears and makes them ring. ( been a year + )
Normal train of thought. Bigger muffler case is bettter. I recently grabbed a used 14” Total flow straight through oval for cheap and put it on. After two days is has to come out. Since it’s the low frequencies bugging me, I was hoping the 14” case would change the hz higher, but it went lower and wider.
I read that people have good luck with 6” round mufflers in regards to cabin noise.
Maybe round reflects sound waves in a smoother pattern than oval even though oval has more sound deadening material in it. ?
I have read pretty much everything including drone occurs when you have a muffler that has two exit points within the muffler?
Stainless can ring more than aluminized steel piping?
Have the dual exhaust tips further out from the bumper. ( I have a big horn edition 2011 )
I was going to try the Ultra flow 6” with a y after it, but since I live where I live the shop wanted 4-500 to put it in after I supplied the muffler and y pipe. lol
I have been thinking of the factory muffler with a j -pipe, and delete the factory resonators as they are probably not tuned right anymore, or add better ones.
Also still the Ultra flow 17223 6”, and if it’s too loud add a Vibrant resonator before muffler.
It would sure be nice to be able to use the Hemifever tune at some point again.
Things were so much easier with my 1969 F100, cammed 302, great sounding and never droned.
Rebuilt motor, MMX +30 NSR NTR cam. Hemifever tune. Mufflex 24”.
Caused severe resonance.
Little to no resonance before the new cam. It all started when I was testing the new tune, remote testing.
Put stock muffler on, still hurt my ears but they were and still are sensitive to whatever happened to them, so put the Diablo 87 tune back on it. Now the Diablo 87 tune with stock exhaust hurts my ears and makes them ring. ( been a year + )
Normal train of thought. Bigger muffler case is bettter. I recently grabbed a used 14” Total flow straight through oval for cheap and put it on. After two days is has to come out. Since it’s the low frequencies bugging me, I was hoping the 14” case would change the hz higher, but it went lower and wider.
I read that people have good luck with 6” round mufflers in regards to cabin noise.
Maybe round reflects sound waves in a smoother pattern than oval even though oval has more sound deadening material in it. ?
I have read pretty much everything including drone occurs when you have a muffler that has two exit points within the muffler?
Stainless can ring more than aluminized steel piping?
Have the dual exhaust tips further out from the bumper. ( I have a big horn edition 2011 )
I was going to try the Ultra flow 6” with a y after it, but since I live where I live the shop wanted 4-500 to put it in after I supplied the muffler and y pipe. lol
I have been thinking of the factory muffler with a j -pipe, and delete the factory resonators as they are probably not tuned right anymore, or add better ones.
Also still the Ultra flow 17223 6”, and if it’s too loud add a Vibrant resonator before muffler.
It would sure be nice to be able to use the Hemifever tune at some point again.
Things were so much easier with my 1969 F100, cammed 302, great sounding and never droned.