Turning the air resonator into free under hood storage

[El_bell]

A few weeks ago, I was cleaning up the engine bay some and thought that I might remove the air resonator (I think that’s what it’s called) that sits above the radiator to free up some space. It’s not like I really needed the space for anything, but the resonator doesn’t exactly do a whole lot besides take up space. I know it does have some practical purpose or it wouldn’t have been installed from the factory. As far as I can tell though, it’s just meant to quiet intake noise, which isn’t very noisy even without the resonator installed.

I noticed while it was off the car that if I cut a hole in the top of it, there might be enough space inside for a small bottle of oil and some rags for quick and easy oil topping off. With a little bit of cutting with a dremel and hinge I found lying around, I was able to make a somewhat decent looking little storage box. Since the section that was previously securing the resonator to the radiator support was now a moving lid, I wasn’t sure if any extra support would be needed to keep it in place. All I had to do though was find a push pin I could easily remove by hand that also wouldn’t fall out on its own and that was good enough. Every edge that was cut was covered in a few layers of duct tape mostly to be quick and lazy about it, but I don’t think it looks to bad for being a completely free project, lol. I thought about cutting off the tube that goes into the air box, but I just covered the hole with duct tape so nothing could get into it, but so I could still use the air box for support holding it up. I originally wanted to use a small 16oz bottle from Dollar Tree, but it proved to let oil seep out the lid. I have to keep the bottle on it’s side due to the space constraints, but I found another bottle that is also 16oz that seals way better than the first one. It’s a little bulkier but still fits in and has a convenient spout built in for pouring. 16oz will probably be enough for at least 1,500-2000 miles in my Saturn. I honestly don’t really top off the oil that often but I would still always keep some in the trunk just in case. This was just a nice little convenience thing for myself, but maybe some others out there with more oil hungry Saturns could benefit from a little storage box like this too. I also threw in a triangle flashlight and a random cooking thermometer in there too. Flashlight because a flashlight may be handy in the future and the thermometer was just to see how hot things would get in there.

A more crazy idea I had after completing this was maybe being able to turn the resonator into an oil reservoir, similar to the windshield washer reservoir. The lowest point on the resonator happens to be right next to the dip stick. With a little custom tubing and a valve to control oil flow and it might be the best thing for an oil burner other than a full rebuild. Maybe I’m overthinking it though, just here to share my weekend project

[alordofchaos]

cool project!

I don't know if it will fit, and have not tested long-term oil leakability, but for oil storage, I have been using a CoffeeMate non-dairy creamer bottle.

I don't like having a funnel in the car for oil and those EZ pour quarts are OK but you can still get some dripping. Was looking at a detergent bottle that has an EZ pour type spout that drains back into the bottle but those are too large.

Then I realized the coffeemate liquid bottle we were trying was a good size. The flip up lid seals pretty good and extra oil from the spout drains back into the bottle. We don't buy these normally, just tried a flavor for a change. Took off the labelling (it's clear plastic underneath), washed it out, works great.

edit: here's a picture of a bottle, without label and lid open

[cujoe_da_man]

I thought that was to catch debris that would clog up the air filter faster. Odd they would put something on there to make it quieter when the engine would be louder than the air it pulls in.

[Signmaster]

Originally Posted by cujoe_da_man

I thought that was to catch debris that would clog up the air filter faster. Odd they would put something on there to make it quieter when the engine would be louder than the air it pulls in.

Not sure if I would want that on a car crossing the border into Mexico. Just sayin'......


And it's surprising how much intake noise can be heard over engines at certain speeds and throttle conditions. I always thought most OEM resonators were sort of overkill, but people like really quiet cars.

[cujoe_da_man]

So, are we talking about inside or outside the car that you can hear it?

[dummo]

I found this on Quora:

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This is a fairly simple explanation, I hope it's helpfull and corrrect. High performance engines have tuned exhausts and intake manifolds. This means the length of of the exhaust and intake is adjusted for maximun power and torque. You may have seen high rise intake manifolds at the speed shop or tuned length extractors. The reason this worksis difficult to get your head around but Ill give it a go. In the intake manifold air is constantly moving backwards and forwards from the valve to the carby or throttle body. Ideally this air wave will arrive at the intake valve exactly when the valve opens , unfortunately this only occurs at certain speeds. If the air flow wave is moving away from the valve when it opens there will be a delay meaning a loss of power. Long intake manifolds work well at low speeds while short ones help at higher engine speeds. The same theory works with exhaust pipes except this time the pressure wave should be moving away from the exxhaust valve when it opens to give maximum exhaust gas extraction. It's an engineers job to work out optimal length for the speed range where maximum power is required.

I look forward to hearing from someone who knows more about this topic. " end quote

Maybe you'd be better off creating a saddle bag type bucket/box elsewhere in the engine compartment just in case there is a true reason for interior volume of the Saturn's intake resonator.

[fetchitfido]

That Quara response is perfectly valid for a question about short vs long intake runners but has NOTHING to do with this mod or anything that bothers the intake pipe between the actual air intake location and the throttle body/carburetor.

There's only 2 issues with doing this mod...if it's still connected to the intake pipe then whatever debris you let into the compartment WILL* get sucked into the engine and it totally negates the ease of access to everything underneath it to gain by throwing it out.


*CAN DESTROY ENGINE. The resonator is between the air filter and the throttle body...there is no air filtration to keep debris out of the engine that enters here.

[El_bell]

The resonator actually connects below the air filter, so engine damage wouldn’t be a concern even the pipe that slides into the air box wasn’t blocked off.

[lanxer57]

I always wondered what that box was for... I thought it looked like something meant to control the pressure of air when it first enters the intake, kind of like the "buffeting" sound that can be heard in some cars when one window is opened on the highway. It is definitely not sealed either. Has anyone tried driving without it just to see if it makes a difference?

[Signmaster]

Originally Posted by cujoe_da_man

So, are we talking about inside or outside the car that you can hear it?

You would hear it under certain conditions inside the car as well as out.

The flow of air through the intake is interrupted when the column of air hits the closed intake valves. This creates a pressure wave that bounces back into the intake system, fighting the incoming air. This is taking place for each cylinder, so you have multiple pressure waves trying to bounce back, while at the same time intake runners are seeking incoming air.

Most resonators simply allow an expansion chamber area to allow the pulses to be dampened and slow the pressure waves coming out. Done properly a resonator will actually aid intake flow under certain conditions as well as reduce noise.


Intake sounds with short runner intakes and individual carbs/throttle bodies and filters can actually be fairly loud and pronounced. Similar to a car with a bad misfire trying to accelerate... that thump, thump, thump, thump....

That is because the air column has very little restriction, and virtually no dampening when the pressure wave is created. It simple expands as it exits the air filter.

[PrestonIII]

On my 1st gen '94 SL2, the air pipe that runs across the top of the radiator is a straight pipe. There's no resonator box.

That resonator is there to quiet the input air noises. It must not have been thought about in the early cars.

Preston

[El_bell]

I knew that the 1st gens had a longer air resonator, But I have never considered if one design works better than the other or not.

[SW2outoftheblue]

Originally Posted by cujoe_da_man

I thought that was to catch debris that would clog up the air filter faster. Odd they would put something on there to make it quieter when the engine would be louder than the air it pulls in.

I noticed that without my intake resonator, the intake whistled like blowing on a pop bottle at maybe 3k and 4.5k RPM. Suuuper annoying because 80 MPH is about 3k RPM with my tires/ratios.