Right, I've been looking at a lot of induction setups, and tried quite a few. And I've been thinking a lot about the science behind what makes different setups behave differently. I'm not an expert in tuning, but I've spent a few year in process engineering, so I've got a fair idea of what I'm talking about. I could be wrong in all of this, but im pretty sure im not.
Before i go into it, I havent dyno tested any of these, and even if i did, it doesnt explain the whole story. For me, the focus is on responsivness.
When people get v6 airboxs they often complain about a lack of response and just get a boomy noise when they put their foot down. This is because they have a larger intake hole. The venturi effect.
Just because there is a bigger hole, it doesnt necessarily mean more flow (sure, theres the potential for more flow) but it doesnt happen immediately. Imagine suckingwater through a straw, and then sucking it through a drain pipe, theres more potential flow but its harder to suck it at the same rate if the suck is the same pressure. (suck = low manifold pressure due to inlet stroke of a piston). This happens a lot at low revs.
So when you plant your foot down with something like a BMC of a v6 airbox, there is a lag due to the low velocity of air (which i think is responsible for smoothed torque curves). This lag causes a high difference in pressure between the inlet side of the filter, and the engine side, because the air drawn in my the engine cannot be sucked into the filter houseing quick enough.
Any performance gains on a dyno will not show this lag.
On the other hand, if the inlet hole is too small it will cause a restriction. Which i believe the standard setup is, (that sucking sound).
The venturi effect:
The high velocity air is needed for responsiveness.
Notice the shape is similar to the inlet of an ITG Maxogen? (which DOES drive well)
My solution:
With the focus on response and cheapness, after experimenting with a lot of configurations I've gone for this:
Standard airbox with standard fitler (they aren't BAD filters, but I'll be changing to a KTR panel filter just for the cheapness of it!)
Acoustic calve removed.
Upper cold air feed removed and replaced with a loosely fitting caf running from the floor.
The theory behind it is to bypass the need for a finely tuned inlet port (maxogen) and ensure the inlet pressure and air supply flow rate are high enough so as not to cause restriction.
The ram effect esque caf does this. The high speed air ensures there is plenty of cold air to be sucked through the filter, and its loose fitting to the airbox ensures that the length of the caf wont cause a restriction when driving at low speeds.
I've also put a samco induction elbow on partly for looks and partly due to its constant diameter.
So, all in all I'm verry happy with this setup and I wont be spending any more on induciton kits. (unless someone buys me a JMS RS2).
Before i go into it, I havent dyno tested any of these, and even if i did, it doesnt explain the whole story. For me, the focus is on responsivness.
When people get v6 airboxs they often complain about a lack of response and just get a boomy noise when they put their foot down. This is because they have a larger intake hole. The venturi effect.
Just because there is a bigger hole, it doesnt necessarily mean more flow (sure, theres the potential for more flow) but it doesnt happen immediately. Imagine suckingwater through a straw, and then sucking it through a drain pipe, theres more potential flow but its harder to suck it at the same rate if the suck is the same pressure. (suck = low manifold pressure due to inlet stroke of a piston). This happens a lot at low revs.
So when you plant your foot down with something like a BMC of a v6 airbox, there is a lag due to the low velocity of air (which i think is responsible for smoothed torque curves). This lag causes a high difference in pressure between the inlet side of the filter, and the engine side, because the air drawn in my the engine cannot be sucked into the filter houseing quick enough.
Any performance gains on a dyno will not show this lag.
On the other hand, if the inlet hole is too small it will cause a restriction. Which i believe the standard setup is, (that sucking sound).
The venturi effect:
The high velocity air is needed for responsiveness.
Notice the shape is similar to the inlet of an ITG Maxogen? (which DOES drive well)
My solution:
With the focus on response and cheapness, after experimenting with a lot of configurations I've gone for this:
Standard airbox with standard fitler (they aren't BAD filters, but I'll be changing to a KTR panel filter just for the cheapness of it!)
Acoustic calve removed.
Upper cold air feed removed and replaced with a loosely fitting caf running from the floor.
The theory behind it is to bypass the need for a finely tuned inlet port (maxogen) and ensure the inlet pressure and air supply flow rate are high enough so as not to cause restriction.
The ram effect esque caf does this. The high speed air ensures there is plenty of cold air to be sucked through the filter, and its loose fitting to the airbox ensures that the length of the caf wont cause a restriction when driving at low speeds.
I've also put a samco induction elbow on partly for looks and partly due to its constant diameter.
So, all in all I'm verry happy with this setup and I wont be spending any more on induciton kits. (unless someone buys me a JMS RS2).
