Had a play about with my Puma.

[Glenn_]

There are a few people on her obsessed about cars sucking water up. I work on a fleet of shity vauxhall combos where the induction pipe is in the front grill near the bonnet and the amount of vans we have had to get the water out of them is unreal.

 

[oilburner]

I've just recently read a sorry tale about a Civic Type R FD2 owner whose car sucked up a load of water due to a poorly located CAI and was left with a huge bill

 

[FireFly90]

So why do people remove the resonator. And what does the resonator do?.

In short - I assume people remove it for noise? What does it do; it makes your engine run smoother.

The technical:

There is a frequency to the flow of air, and anyone who knows anything about 2 strokes may well know about this (powerbands, expansion chambers etc.).

The little black box has an entry at which air entering the intake will flow in and over. If you imagine it like blowing over the top of an empty bottle, it will make a noise as air flows in and over the neck, although the air inside the bottle will have a higher air pressure. This means that when the flow of air over the bottle neck stops, or reduces, the air pressure in the neck will equalise the flow of air over the neck. It's part of a thing known as Helmholtz resonance.

What this means is that your air intake is designed so that the little black box with the neck captures air and releases it when it is required to do so in order to keep the 'feed' of air to the inlet (and this each cylinder) even.

For anyone that has venture into thermodynamics or aerodynamics at all, there is a whole series of topic related to the effect of resonance and frequencies on the flow of air into the engine, valves etc. The helmholtz resonator will have a big effect on these things.


In summary - with the resonator on you'll have a smoother power curve and the engine will run a lot nicer; without the resonator you may get a little more induction noise, but you'll also be likely to get a rougher power curver and may experience some very slight side effects to how smooth your engine runs or the response/pick up

We glossed over summit like this in one of my lectures, I'm wondering whether i should have left mine in, instead of ripping it out =P

 

[yippeekiay]

Top info cj2013 :thumbs:

Explained in a roundabout way why my old 2 stroke 125 went like a rocket. It had an expansion chamber that made the engine deliver it's power more linear but actually stiffled the output. Once I fitted a blank to that chamber it was much slower to 6k rpm then went like a banshee and for some reason doubled the power output :lol:

Happy Days!!! :happee:

 

[XIIVVX]

There are a few people on her obsessed about cars sucking

<_<

 

[cj2013]

Top info cj2013 :thumbs:

Explained in a roundabout way why my old 2 stroke 125 went like a rocket. It had an expansion chamber that made the engine deliver it's power more linear but actually stiffled the output. Once I fitted a blank to that chamber it was much slower to 6k rpm then went like a banshee and for some reason doubled the power output :lol:

Happy Days!!! :happee:

my degree is in automotive engineering so had entire modules on this stuff

on a second note, without an expansion chamber you'd lose power as it would have an effect on port blocking.


a lot of things are just a choice between driveability and performance, but you won't get the performance without a better filter, plenum etc

 

[Glenn_]

Your a clever man matey.