R56 Cooper - Modified Intake Silencer
#76
niice! id say its a bit a both. there are many factors that play into the MPG games so i wouldn't directly correlate this mod with your improved MPG however it would make sense that there would be some increase in MPG because of the smoother/more efficient air flow. either way, sounds like you approve
#77
#78
#80
The silencer does just what it's name implies - it makes the intake charge air slower and silent .... by taping the holes you make it smoother and speed up the air ( less turbulence ) think VIP air tube - and it makes a bit more noise. It 'might' give you a tiny bit more power , but that is up to you to decide...
#84
#86
yes it works but you are then sucking air from right next to the engine block which is very hot. the tube connects to the front where it can get some cooler air. so if you like the sound, go ahead and tape 'er up... or just get DDM intake and it will howl even more.
#87
#88
#90
As for the math on what the holes are doing in this resonator, I cannot provide it to you, nor have I ever seen it published but I am sure it is available somewhere. Basically, the holes provide turbulence during the rush of cold air to the intake, which is eliminated by every aftermarket intake manufacturer for this system - most by putting a straight drainpipe like tube to the airfilter.This turbulence cancels noise created by waves of air pressure moving swiftly through the chamber by creating high/low and out of phase shock waves in a tight area. As I understand it, air moving at high velocity creates friction which we hear as noise, an "intake roar". Ever hear a set of 12 open carbs on a '50's Lamborghini 12 cylinder? I think there is a generation of young drivers that come from playing Nintendo "Tron lightcycle" that just don't get what benefits in feedback to the driver of the whole old school carb linkage/induction noise gives.
The same effect that covering the holes can be made by any piece of pipe in an appropriate diameter for the volume. You can pay $200 for this pipe, or get one at Home Depot in the plumbing section, the engine doesn't care how much you paid for that performance. Taping these holes essentially is creating that "ideal" tube out of what is stock. What I offered by my post was a choice in the tape material that would stand up to the heat better than Gorilla tape, hell - they tape airplane wings together with this stuff, it is proven strong!
Do some $200+ intake systems perform better than duct tape? Of course they do, but I have to point out that ALL of them use something like a K&N filter and then go on to claim some vague HP increase that is within 1% or so of what K&N claims for their filter alone. But is it just good enough for the street, not the race track? My opinion is spend the $5 on the duct tape and $195 on a driving school,... decide later if you have to have the bling.
A minor caveat to my rant - it is possible that at the highest rpms there could be some undesirable effects, I wonder if poking a hole in the tape on two of the smallest holes or making a "tent" to obstruct and disperse airflow might not be a good idea? A poster upthread made this same observation at WOT, that it was cavitating and causing an alarming popping noise.
Last edited by RockAZ; 06-21-2013 at 01:34 AM.
#91
It's there to quiet the intake.
All OE setups do this to eliminate noise/frequencies that engineers/testers/grandmothers/people who hate cars deem undesirable.
For the engineer, I've heard that the noise.. Is actually "bad" for fuel economy. The chambers smooth out the power pulses generated by the airflow as the intake valves snap shut. The air rushing in was pushed by the air behind it.
When the air gets the door, er.. Valve slammed in its face it makes noise.. And noise is the "growl" we like.
The air has no "cushion" or "relief" left from the covered holes... Normally the air could "rest" in the pockets... It's like changing the length of a trombone... The size and shape of the chamber changes the sound.
Trust me. You harm nothing other than an engineers pride when you cover them up.
The following users liked this post:
930 Engineering (03-21-2021)
#92
http://en.m.wikipedia.org/wiki/Helmholtz_resonance
It's there to quiet the intake.
...
The air has no "cushion" or "relief" left from the covered holes... Normally the air could "rest" in the pockets...
It's there to quiet the intake.
...
The air has no "cushion" or "relief" left from the covered holes... Normally the air could "rest" in the pockets...
#93
Join Date: Mar 2009
Location: Eastern Long Island, NY
Posts: 1,980
Likes: 0
Received 1 Like
on
1 Post
danjreed and RockAZ - awesome explanations! It helps to understand the dynamics of an engine/intake in order to decide whether taping off holes is worth it or not. I taped mine off with duct tape 2 years ago - I'm convinced theoretically that there's no difference between this and an aftermarket tube, but I may opt for the bling down the road.
#94
After two years I would be curious about the condition of that tape now. Here in Arizona, it would have rotted and flaked away, I'm sure. That aluminum tape I put in will outlast the plastic in this heat. You can find this $5 package in the exhaust section of any popular auto parts store, and it is enough to do two cars.
Since my K&N filter has not yet arrived, I have been driving it with the stock air filter and I can definitely feel an improvement in the throttle response and a bit more noise. Stock muffler and exhaust resonator still in place, but I swear there is more growl coming from the tailpipe.
Since my K&N filter has not yet arrived, I have been driving it with the stock air filter and I can definitely feel an improvement in the throttle response and a bit more noise. Stock muffler and exhaust resonator still in place, but I swear there is more growl coming from the tailpipe.
#96
Tried out the duct tape modified intake silencer today, covered all the holes and love the sound! I see that VIP makes a straight pipe (AIRVIP2) intake silencer delete, and am now considering this more permanent install. Does anyone know whether other suppliers are selling products like this?
#97
I removed my resonator for 2 days and it drove me insane. at 3000+ rpm the drone was sooooooo loud!!!! above that was a good sound but i also lost 3mpg.
one of the worst things i ever did. seriously. ill make my own intake out of the 2.5" intercooler piping kits on ebay / amazon with a K&N filter.
I tried to tape the elbow but had no tools that could get the tape to adhere. eff it.
one of the worst things i ever did. seriously. ill make my own intake out of the 2.5" intercooler piping kits on ebay / amazon with a K&N filter.
I tried to tape the elbow but had no tools that could get the tape to adhere. eff it.
#100
Oh I am so glad that I finally found this. I didn't know what that black square box is called so I had to use different search terms and go through tons of threads.
If the silencer does nothing more than sound-dampening, then I want to remove the whole things. I thought it was there as a pre-filter filter to remove water and other debris so that they don't even enter the intake box. If that is not the case, I will run a straight pipe from the intake duct to the intake inlet (?).
If the silencer does nothing more than sound-dampening, then I want to remove the whole things. I thought it was there as a pre-filter filter to remove water and other debris so that they don't even enter the intake box. If that is not the case, I will run a straight pipe from the intake duct to the intake inlet (?).