anyone mod there airbox intake?

[Kspalla]

The issue i see here is that these bikes were de-tuned to make them a "Starter" bike and perhaps this was one of those restrictions along with the exhaust to take back a few horses. open this puppy up a little and remain happy with her

 

[CParnell]

That is the best explaition I've ever read as to why NOT to chop up an airbox.

Image downloaded and saved.

IMHO, yes and no. People have been doing this for eternity. The first mod most people did on old bikes was to ditch the air box and put pod filters on. That is why when you do something like this, you have to check your tune afterwards. Same as re-jetting the carbs on an old bike after putting pod filters on.

 

[Halon]

The article isn't saying that cutting our airbox will lessen our power; it's just implying that in most cases the airbox is designed by the engineer to operate in harmony with the engine to provide adequate airflow to the engine for a targeted powerband. The section toward the end regarding race teams removing the airbox on tracks that are designed in a way that would often have the engine in lower rpm's indicates to me that (if I'm comprehending this properly), less restriction is good in lower rpm ranges. However the principle then would imply that at higher rpm that the air flowing into the box creates a constant pressure against the draw of the engine. If you remove the restriction and then rev to the moon, the air traveling into the intake runners has had no confine or restriction. At lower rpm ranges this may not be as large an issue as the volume of air CFM is a lower requirement, so the draw agianst the atmosphere is most likely more than sufficcent. As these values increase with higher rpm's you begin to need ways of keeping the air smooth and behaved as the velocity increases. The air going into the engine at this point would be very chaotic and unorganized. Imagine trying to throw a bucket of water through a small opening and how much could accurately be deposited on the other side; now imagine the same excercize but instead this time with a hose and nozzle. The restriction of the hose and nozzle ensures that the water coming out has had adaquate time to calm and travel in a uniform path instead of just being thrown at the objective.

I think I understood this article anyhow.

 

[Marthy]

I found this schematic of the FZ6R Airbox at Motorcycle and ATV reviews, specifications, prices, used motorcycles by PowerSports Network, if there is some way to tie the air intakes on the cowling into the air box to make a ram air system, that would be pretty cool :thumbup:

I can't remember where I saw that post way back then... Now that I have my exhaust what Ineed to block to get ride of the poping? My bike is not really poping (doing bla bla bla bla bla when I close the throttle instead of a nice brrrrrrrrrrrrr) lol Thanks!

 

[yellowfz]

Your in luck , I just did this on mine .
Under the Air Box there is a device that lets Air into the Motor AIS (smog pump) remove it and block off the inlets that are on the engine .
Here is link :http://www.600cc.org/forum/f91/howto-install-graves-ais-blockoffs-18684/, I also cut the air box just under the filter .
I just went to A.Z. (auto zone) and got some Dorman . Bypass Caps , part # 02253 used the 5/8" ones , and used the old hose clamps off the hoses to secure the caps , 2 at engine and 1 on the air box .
Hope this helps .

 

[Spunky99]

Minor points.

1. opening up the airbox top will allow more air into the throttle bodies and lean the mixture. The EFI may adjust the mixture some and maybe not resulting in a lean condition. Burning a valve is not a plus on this motor. You will have to check the color of the ceramic on the plugs to be sure the mix is OK. Pain in the butt tho....

2. The graves backoffs are post fuel/air mix and burn so this is fine and will help relieve the popping on de-acceleration. I will do this to my bike this weekend along with installing the NGK Iridium plugs..last thing on my mod list but too lazy and way to sick to finish.

3. I noted that the install of a K&N air cleaner into a stock airbox is the same as having a stock air filter setup. IE, No change in air pressure. The stock Power Commander maps are all configured with a stock airbox/air cleaner element and only addresses a couple of different exhaust configurations. I tried a few and found the one that worked best for my custom exhaust install. There is no need IMHO to mod the airbox as there is plenty of air volume at the throttle bodies. If you want to install an R6 throttle body and then mod the airbox, that might be a good pairing of mods but the bottom end will be gone and you will have a very narrow power band to work with. A total waste of the efficient power we now have.

 

[Marthy]

Minor points.

1. opening up the airbox top will allow more air into the throttle bodies and lean the mixture. The EFI may adjust the mixture some and maybe not resulting in a lean condition. Burning a valve is not a plus on this motor. You will have to check the color of the ceramic on the plugs to be sure the mix is OK. Pain in the butt tho....

2. The graves backoffs are post fuel/air mix and burn so this is fine and will help relieve the popping on de-acceleration. I will do this to my bike this weekend along with installing the NGK Iridium plugs..last thing on my mod list but too lazy and way to sick to finish.

3. I noted that the install of a K&N air cleaner into a stock airbox is the same as having a stock air filter setup. IE, No change in air pressure. The stock Power Commander maps are all configured with a stock airbox/air cleaner element and only addresses a couple of different exhaust configurations. I tried a few and found the one that worked best for my custom exhaust install. There is no need IMHO to mod the airbox as there is plenty of air volume at the throttle bodies. If you want to install an R6 throttle body and then mod the airbox, that might be a good pairing of mods but the bottom end will be gone and you will have a very narrow power band to work with. A total waste of the efficient power we now have.

I'm wondering how the ECU can figure out how to adjust the mixture without reading exhaust temps? I can feel howlean the engine is with my exhaustand stock ECU. I'm keeping the rev under 6K until I get the PC or JB.

I think the engine will adjust itself for ambiant temp change and few little things like that. But for some major mod like airbox or exhaust you need a PC or JB, no question...

 

[DocFZ]

I feel leaving it be is the best option. I doubt any of us are smarter than yamaha engineers

 

[Spunky99]

I'm wondering how the ECU can figure out how to adjust the mixture without reading exhaust temps? I can feel howlean the engine is with my exhaustand stock ECU. I'm keeping the rev under 6K until I get the PC or JB.

I think the engine will adjust itself for ambiant temp change and few little things like that. But for some major mod like airbox or exhaust you need a PC or JB, no question...

I wondered that too...Is the ECU clairvoyant? I heard that it can make some changes based on RPM and temp. It does check those things.

I watched a guy change the stock pipe and air cleaner on a YSR50 at the track from stock and race in the modified class. He didn't re-jet and on the next to last lap we all heard a tire skid. It was funny because my buddy just said something to the effect that the guy's bike sure sounded good out there even though it was being killed by the NSR50's and was in next to last place ahead of a NSR50. He was the only YSR50 on the track. He seized the motor because it was running too lean. Water cooled motors have a distinct advantage.

 

[dart1963]

another article on the whole airbox thing...

Resonant Air boxes: Theory and Applications

"Years ago, before airboxes were designed as resonant systems, it used to be popular to cut additional holes in the air box to allow more air flow for high rpm. This is no longer a good idea.
.....
....
By altering your air box in any significant fashion, you're most likely going to cost yourself three to five hp in the mid range, and gain nothing measurable at high rpms."

 

[Marthy]

another article on the whole airbox thing...

Resonant Air boxes: Theory and Applications

"Years ago, before airboxes were designed as resonant systems, it used to be popular to cut additional holes in the air box to allow more air flow for high rpm. This is no longer a good idea.
.....
....
By altering your air box in any significant fashion, you're most likely going to cost yourself three to five hp in the mid range, and gain nothing measurable at high rpms."

You are right. But we can say the same thing about intake runner lengh, headers primary lengh... When the engineer desing those on the comfort of there office behind a desktopit all work good. But it's just good for a very small RPM range.

 

[yellowfz]

I don't know about the limited capacity of the ECU on these bikes as to whether it will react as the ECUs I work with in Autos , but they can compensate for minor variances , such as CIA (cold air intakes) and headers , cams , blowers , turbos , are where the tuning comes in , that said , are the ECUs on our bikes that sophisticated ? 32bit don't know memory size , most cars are 512k to 1mb memory (flash ROM) .
In autos you have a VE table for NA (naturally aspirated) running , when you go to boost that is a different game then , cams affect the air mass and cylinder volume and vacuum as do forced induction (which can lean out a engine and cause knock if not retarded , so add fuel , pull timing) .
I would love to be able to see the ECU MAPs of one of our bikes , I bet our ECUs can be flashed with new data in the ROM just like any other ECU .
Intake Resonance is for quietness or quietening , of course a motor runs better when it doesn't have to struggle for air .
Letting more air in at the air box only affects the flow of air , the engine can only take in what the engine can get through the throttle body no more , so it is not going to lean it out , it will just be more efficient and not have to pull from a small area .
Sorry for the long boring post , just thinking out loud .

Note after doing mods to air box and AIS bike does respond a lot better .

 

[Spunky99]

Question for you. I always thought the restricted air matched the jetting and if you opened it up it could run leaner. Did they design the airbox to deliver all the air the TB's could use? In that case opening up the airbox wouldn't do anything for the TB's.
Also can you explain or show the airbox mod and AIS mods you did?

I don't know about the limited capacity of the ECU on these bikes as to whether it will react as the ECUs I work with in Autos , but they can compensate for minor variances , such as CIA (cold air intakes) and headers , cams , blowers , turbos , are where the tuning comes in , that said , are the ECUs on our bikes that sophisticated ? 32bit don't know memory size , most cars are 512k to 1mb memory (flash ROM) .
In autos you have a VE table for NA (naturally aspirated) running , when you go to boost that is a different game then , cams affect the air mass and cylinder volume and vacuum as do forced induction (which can lean out a engine and cause knock if not retarded , so add fuel , pull timing) .
I would love to be able to see the ECU MAPs of one of our bikes , I bet our ECUs can be flashed with new data in the ROM just like any other ECU .
Intake Resonance is for quietness or quietening , of course a motor runs better when it doesn't have to struggle for air .
Letting more air in at the air box only affects the flow of air , the engine can only take in what the engine can get through the throttle body no more , so it is not going to lean it out , it will just be more efficient and not have to pull from a small area .
Sorry for the long boring post , just thinking out loud .

Note after doing mods to air box and AIS bike does respond a lot better .

 

[yellowfz]

I just did a reading with my portable wide-band and got 10.9-11.2 AFR @ 4000-5000 rpm , pretty rich ( no bung , just in exhaust stream) .
Will have to describe Mods have put everything back together and didn't take any pics , but will see if can use the drawing from the manual to show what and where .
Basically I just took off the AIS and rubber capped the places the hoses came off of (funny the AIS looks as if though it sucks air or exhaust/fuel not push air , attaches to top of air box , unless the engine creates more of a vacuum than the throttle bodies , the air is pulled into the air box not the engine , after browsing through the manual I see that the AIS is a direct path to the exhaust valve port just above the valve , yikes , how weird) , I activated the valve to see what it does and it just does a restriction causing flow differences (12v +, - to poles to activate while blowing air through it) .
Cut the snorkel on the air box off about 2" from the end removing the tube and opened it up to about the size of the filter , the intake is loud now , can hear it sucking air in sync with exhaust note , but not to bad .
And S.O.T.P. dyno says it is pulling harder .

Again just rambling .

 

[Spunky99]

The reason I'm interested is that I will be installing the backoff plates and removing the AIS and installing the Iridium plugs and rechecking the sync. As long as I'm in there I was interested in the airbox mod. So you only cut off 2" of the snorkel or did you do something else?

I just did a reading with my portable wide-band and got 10.9-11.2 AFR @ 4000-5000 rpm , pretty rich ( no bung , just in exhaust stream) .
Will have to describe Mods have put everything back together and didn't take any pics , but will see if can use the drawing from the manual to show what and where .
Basically I just took off the AIS and rubber capped the places the hoses came off of (funny the AIS looks as if though it sucks air or exhaust/fuel not push air , attaches to top of air box , unless the engine creates more of a vacuum than the throttle bodies , the air is pulled into the air box not the engine) , I activated the valve to see what it does and it just does a restriction causing flow differences (12v +, - to poles to activate while blowing air through it) .
Cut the snorkel on the air box off about 2" from the end removing the tube and opened it up to about the size of the filter , the intake is loud now , can hear it sucking air in sync with exhaust note , but not to bad .
And S.O.T.P. dyno says it is pulling harder .

Again just rambling .

 

[yellowfz]

Browsing through the manual ran across the FI System section , so basically a PC (Power Commander) alters the Injector Timing , Injector Duration for longer duration more fuel , less duration less fuel , pretty simple stuff .
To answer , no I cut the whole bottom off of the air box that hangs over toward the front of the bike , so snorkel is gone and a large hole is just under the filter the size of the filter .

 

[Spunky99]

Browsing through the manual ran across the FI System section , so basically a PC (Power Commander) alters the Injector Timing , Injector Duration for longer duration more fuel , less duration less fuel , pretty simple stuff .
To answer , no I cut the whole bottom off of the air box that hangs over toward the front of the bike , so snorkel is gone and a large hole is just under the filter the size of the filter .

So I take it you won't be riding in the rain?