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Air box mod ?

# two

# two

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What is the airbox mod? I already have the power commander, yosh slip on and bmc air filter. This winter i'm going to pull the header and look at drilling out the cat. I would also like to get more air in, but don't know what or where to modify the air box. thanks # two.
 
I don't have a picture of it but, under the air filter and in the shape of the air filter, you would cut the bottom out of the airbox below the air filter. You will see, under the filter, a snorkel of plastic. Your goal is to remove this out to the edges where the airbox sides go vertical toward the air filter.

The extreme method is re-routing cables, etc to clear the area underneath and through the frame to allow maximum air intake. I'll see if I can grab a pic and attach it here.

That was easy... :D Found the original Lars pics, hence the nickname LARS Airbox Mod.

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Since this seems to be the only thread with pics on the subject after a search here, I'm making this a sticky for the GEN II mods page.

Special thanks to Lars over at FZ1OA for the borrowed phtotos! (Gotta give credit where credit is due!)

:D :tup:
 
Just to add to this. On the bottom picture it's ok to cut that piece that is sticking up at the front of the airbox. In other words you can just cut it straight across. There is no point in leaving it there and I believe that in a later thread Lars went back and cut it off. I cut it off when I did mine as well.
 
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NJFZ1 said:
Just to add to this. On the bottom picture it's ok to cut that piece that is sticking up at the front of the airbox. In other words you can just cut it straight across. There is no point in leaving it there and I believe that in a later thread Lars went back and cut it off. I cut it off when I did mine as well.
Click to expand...

Now I have to go look at mine.... not sure if I cut that off or not! Thanks!!!
 
What benefits do you find with this mod and why didn't (or did) Yamaha engineers design the air box as they did? I put in a K&N High Flow filter recently and think I have improved low end torque?
 
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Polestar said:
What benefits do you find with this mod and why didn't (or did) Yamaha engineers design the air box as they did? I put in a K&N High Flow filter recently and think I have improved low end torque?
Click to expand...

I can't tell you why Yamaha engineers designed the airbox as they did, but in theory the stock opening is large enough to support the horsepower of the engine. The problem is that the design of the airbox forces the air to make a sharp turn. Seems that opening the airbox up lets the engine breath a lot better. Will be of most benefit once you do exhaust mods as well since more air in equals more air out.
 
Air Box Mod HP Gains ?

I have an 08 FZ1 with a K+N / acraprovic end can / PCIII + Dyno run / remap completed with a RWHP = 146.
Looking at the tread is looks like the Max HP I could gain from an Air Box mod + Cat gutting and Flies Mod would be 6 Hp at most would this be correct. If I did the above mods I presume I would need a remap again .. Newbie so just asking a question..
 
JRL said:
I have an 08 FZ1 with a K+N / acraprovic end can / PCIII + Dyno run / remap completed with a RWHP = 146.
Looking at the tread is looks like the Max HP I could gain from an Air Box mod + Cat gutting and Flies Mod would be 6 Hp at most would this be correct. If I did the above mods I presume I would need a remap again .. Newbie so just asking a question..
Click to expand...

The Flies Mod isn't going to give you more top end HP since they are already fully open by then. I would say that is a very good HP number (146). Would expect gutting the cat and the Air Box Mod would net you another 3-4 HP. Not sure if you would need another dyno tune or not. Guess it depends how rich or lean your tune is right now. If a little on the rich side then I'd say you would be fine.
 
Airbox mod

Hi I did the airbox mod on Saturday morning, Really easy to do I used a jigsaw and a file 10mins. I noticed a bit of difference you can hear the air intake working which is a good, Follow the links on these threads it is really easy to do.
 
The shape, volume, and placement of the air cleaner and enclosure are far more complicated than just the job of holdng a filter for the incoming air. Cycle World has had a few articles on the subject over the years and when all is said and done, the unit provided with the stock bike is generally far better over the entire RPM range than any simple cut-out is going to provide. Getting a few extra H.P. at max RPM my be possible but there is usually a higher price that is paid in the lower to mid RPM range or in transition areas where the stock box has been made to smooth the power delivery. Most people make the mistake of converting more sound (loudness) into more power. In the sixties and seventies many riders shoveled their stock boxes for individual air cleaners because it sounded "cool" and looked like it had to be working better than the cluttered look of the stock box hiding the carbs. I did it a few times. It pleased the eyes, but even with rejetting and some other work it didn't perform especially well. Often off-idle performance was horrible even when max H.P. at WOT was a little better. F.I. systems make it a bit better to control fuel metering, but I'd still be very careful when doing a non-reversible modification to the intake track.
 
Im getting my FZ1 06 dynoed tommorrow asked expert who advised me not to take out cat because unless it is in a link pipe like the R1 you can lose power, With the FZ1 the headers are 4-1 removing the cat would upset the flow as the cat helps it flow into 1 where as the R1 4-2-1 then cat you see. He said best bet is a full system specially designed for the flow or slip on with cat. Hope this helps Cheers
 
Buildercher said:
Im getting my FZ1 06 dynoed tommorrow asked expert who advised me not to take out cat because unless it is in a link pipe like the R1 you can lose power, With the FZ1 the headers are 4-1 removing the cat would upset the flow as the cat helps it flow into 1
Click to expand...

:shaking head::eyebrow::hellno:
 
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The airbox design has a lot to do
With EPA emissions.
There's enough documentation on the added horsepower from a better breathing engine...so I'm glad I did it.


Sent from my iPhone using Tapatalk
 
So,, a gazillion dyno graphs posted all over the internet on a gazillion different make and model bikes, showing the increase in torque and horsepower from generously cutting open the airbox should, at least, prove that "most" bikes can benefit, and in most cases it's all across the RPM range.

I think, Especially on a commuter bike like the FZ1, the airbox is a noise reducing tool. On a repli-racer, maybe the Helmholtz resonance is tuned more for performance but on a FZ1, Z1000, Ninja 650, (ie: designed-for-the-masses commuter/street bike) it's all about EPA noise spec's.

I know the engineers do an awesome job designing every aspect of our bikes, even the Airbox and exhaust. BUT, their #1 priority is "selling" bikes and to do that they MUST meet EPA standards before they can even bring it to market,,,, so meeting EPA criteria is PRI-1,,, even on repli-racers. My point is, even though they are smart, good,,,, even great engineers their hands are tied to some degree and the air intake system and exhaust system are their best tools to meet these stringent noise and emissions regulations so the "performance" of both is a compromise at best.

FWIW: If I were to design the Airbox or exhaust, knowing that people are usually willing to modify their bikes, I would 1st design it so that it would meet EPA requirements but also so that the engine WOULD perform to it's potential once the private owner modified it,,, but that's just me.

This video isn't an FZ1 but you may find it interesting. Shows the dyno run for stock, slip-on and then the airbox mod. Of coarse this is just ONE of the many well documented examples of HP and torque gained by these mods.

Leo Vince Install- Kawasaki Ninja 650r part3 - YouTube
 
Yes to the above. It's not like the GenII has just come out and the path to better performance hasn't been studied. This 6 year old design has a significantly restricted exhaust with two cats and an exup valve (shown to be a sound control device at best) and on the intake side, a snorkel with a small size cross section. The design of the snorkel is almost certainly driven by sound control. . . . Stock bikes make around 75hp at 7K rpms while a "fully modded bike" (full exhaust system, modified airbox, filter, flies, PC with a proper map, ignition module) is making about 100hp. This is power that you will feel just about every time you ride. Take away the airbox modification and performance suffers noticeably. In the lowest of the rev range (<2Krpm) the exhaust and intake mods likely do hurt performance some. Everything above is gains. Noise is definitely increased when the snorkel is removed. . .

Certainly there are some well designed factory intake and exhaust systems not to mention bikes with proper fuel / ignition mapping and smooth snatch free performance. The GenII is not one of them. It is corked up on both the intake and exhaust sides not to mention computer controlled secondary butterflies that numb performance. It also suffers (particularly the early years) from snatchy throttle resulting from deceleration fuel cut. Some of the fixes aren't cheap but they have been well discussed in both forums. Search!
 
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The air intake is not a Helmholtz resonator.
The pulsations generated by the intake cycles (2 per revolution) happening at twice the rpm of the engine have to pass the volume of the intake chamber above the filter and the resistance of the air filter itself. High frequencies are easily filtered out and will not make it to the ouside box, where the snorkel is.
I believe this set up was designed to even out the air flow across the filter surface perhaps, avoiding a saturation area in the middle. Those who have done the modification can report back whether the filter is much more dirty in the center or it is getting dirtier in a shorter time.
It may have been designed to match the maximum capacity of the exhaust system with the cat converter in place. Allowing too much air intake would impair the cat converter function
 
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