Some Car Guy
Well-Known Member
So if you don’t get the length just right, do you just end up moving the drone around?
No. You are trying to reduce drone from 100% to 0% at the same rpm.So if you don’t get the length just right, do you just end up moving the drone around?
It can cancel all drone if you get the right combo. In my 62, I've been able to get 100% elimination, my 64 is at about 90% - that's why I haven't finished the final permanent weld. I need to drive the 64 a bit more to fine tune it. I will get it to 100%.So they don't stop all drone, just at a certain rpm, say 2,500rpm at 55mph?
They will stop all drone, if the tuned length is correct.So they don't stop all drone, just at a certain rpm, say 2,500rpm at 55mph?
I'm thinking the dead pipe gets just as hot as the regular exhaust does?
"warm " is rather subjective. Without any internal flow at speed and with normal ambient exterior air flow, they are IMO likely never to get close to the heat of the regular exhaust.plus, they're directly next to the regular pipes, so they'll get pretty warm. Never IR gun temp measured them though.
That is if your drone is a single frequency and only at one frequency (not a given). This solution here is tuned to 1/4 wave, which means it will also cancel other frequencies but maybe not as much, or wanted to or not, in 1/2? octaves. Nothing is 100% canceled, but enough to likely be masked by all the other frequencies at play.They will stop all drone, if the tuned length is correct.
There is math involved if you are comfortable with that, or you can make it adjustable till you get the right length. Like Charlie Brown is doing.
It does not matter where the 1/4 wave resonators are placed in the system - before or after mufflers - makes no difference. The added pipe length may differ though. Location is mostly a function of where it fits the best."warm " is rather subjective. Without any internal flow at speed and with normal ambient exterior air flow, they are IMO likely never to get close to the heat of the regular exhaust.
What's the thinking on the pre or post muffler location for the 1/4 wave traps? I see both locations shown here.
Why not plumb the 1/4 wave trap with the idea of having proper airflow, pre muffler, locate electric cut outs at the needed distance, and plumb the exit of the cutouts where needed, and kill two birds at once?
Nobody cares about drone with an open cutout.
From Grroogle.....Can someone explain what an exhaust drone is?
I would explain it by using the analogy of foot soldiers marching in sync across a bridge.Can someone explain what an exhaust drone is?
Drone is the result of an issue with the engine tuning...my old school says to fix the tune up and the drone goes away
Drone is the result of an issue with the engine tuning...my old school says to fix the tune up and the drone goes away
Changing the tune up didn't do anything on the one I had that was droning but changing out the mufflers helped a LOT!Got any examples or explanation of this?