Airbox upgrade. Advice please.

OystonIsGone

OystonIsGone

Im looking at an airbox from an M reg Primera. 1.6 would this fit the 2002 k11 1.0 Micra? Also, if this is the only mod I can do, would it be worthwhile?

Pictures attached.

Thanks in advance.

Lee
IMG-20201028-WA0029.jpg
IMG-20201028-WA0028.jpg


Sent from my SM-G960F using Micra Sports Club mobile app
 
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If you do that, I recommend removing that airbox thingie attached and close that hole and keep the total length of the new intake exact the same length as original, bents or not.
 
Well it starts with the diameter where to the airbox connects with the intake, I think the rest can be stuffed in ;) Please put the rubber hose from valve cover to the box and don't release it with a filter, this will give bad fuel economy and worse dyno results
 
richardwbb said:
Well it starts with the diameter where to the airbox connects with the intake, I think the rest can be stuffed in ;) Please put the rubber hose from valve cover to the box and don't release it with a filter, this will give bad fuel economy and worse dyno results
Click to expand...

What is the diameter I need? Thanks.
 
I like the idea of getting a stock but larger Nissan airbox. For best performance N/A just a straight tube. Now I think a Green Storm (or equivalent, the Storm in Green Storm is actually a certain size) will streamline the air a slight bit more which I believe is good for drivabillity and enjoyment. But I do not think the extra cost justifies it, I just bought it second hand. But before you go airbox something it is good to know what you will want next and what you hope to achieve someday. Logical steps are header and cams but do not forget the Nissan upgrades from bigger or faster engines, but you will have to ask around, I am not so aware on this kind of performance upgrades but a logical step is a larger throttle body. And again have a look at Ithishams 80 pound Micra blog, that is how you do it. And don't forget to keep rotating mass as low as possible, free horsepower.
 
.Maarten said:
Here are some pictures:

Formula 1000 rally car air intake/output

Im competing in the junior 1000 championship and am now looking to improve the air intake (mainly) on my 1.0 litre k11 micra, just wondering if anybody had any suggestions on how to improve the air intake or output (exhaust only)
www.micra.org.uk www.micra.org.uk

http://www.humphrisrallysport.co.uk/ sold them in the past
Click to expand...


Wow!! that looks like a beast. I am guessing that would require further mods, to run smooth? ECU or Mapping? As it looks like with the amount of extra air that would take it could need a tweak?
 
Extra air gets measured by MAF and in closed loop (oxygen sensor warmed up / steady oxygen sensor signal) the stock oxygens sensor will pendulate around ideal mixture. So as long the MAF and injectors can take it (and those two can take a lot) standard ecu doesn't have to be replaced. As a rule of thumb ecu programming is only worthwile with turbo and supercharger where the latter is not a real option for a Nissan like ours. If I am incorrect I would like to hear about it :) I have no knowledge about (bike) ITB's or webers besides it slurps and it drives great and it slurps
 
richardwbb said:
Extra air gets measured by MAF and in closed loop (oxygen sensor warmed up / steady oxygen sensor signal) the stock oxygens sensor will pendulate around ideal mixture. So as long the MAF and injectors can take it (and those two can take a lot) standard ecu doesn't have to be replaced. As a rule of thumb ecu programming is only worthwile with turbo and supercharger where the latter is not a real option for a Nissan like ours. If I am incorrect I would like to hear about it :) I have no knowledge about (bike) ITB's or webers besides it slurps and it drives great and it slurps
Click to expand...
That's only true in closed loop, but at wot the ecu switches to internal fuel e ign maps (open loop)

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Please explain? I owned two the same cars (engine, weight, model, hp figure, one was with oxygen sensor and therefore catalyzer and the other without) that rustbucket neared my mileage for 98% where I ask myself today why the heck I want a oxygen sensor, the working of a catalyzer is clear of course

Jorge_EETC said:
That's only true in closed loop, but at wot the ecu switches to internal fuel e ign maps (open loop)

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Click to expand...
 
richardwbb said:
Please explain? I owned two the same cars (engine, weight, model, hp figure, one was with oxygen sensor and therefore catalyzer and the other without) that rustbucket neared my mileage for 98% where I ask myself today why the heck I want a oxygen sensor, the working of a catalyzer is clear of course
Click to expand...
I don't understand the question, oxigen sensor is used to control the fuel trim over time to maintain 14.7 ish afr for efficiency purposes.

But at wot, misture goes rich 12ish afr to prevent knock and make the engine reliable

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With this small mods you can go without a new map since in closed loop ecu will adapt (using maf and o2 sensor).

At wot, they will change your afr, but the change is small, so instead of running 12 afr, you could be running 12.5.
You'll not make any more power by re flashing ecu to correct it to 12, on my gains are reliability

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The fuel map has rpm on one axis and load measured by the value from the MAF Mass Air Flow meter on the other axis. If you get a better air intake that is able to flow more air the MAF will read more air passing it, will therefore add more fuel and perhaps move load sites on the map.
If as I think you were trying to say it doesn't react to airflow then a dirty air filter would throw out the tune.
The o2 sensor effects short and long term fuel trims, this tries to account for anything else that might change over time, a good or bad batch of fuel, more ethanol, a MAF that's got dirty, etc.
 
I am happy with what was just said, I happen to have a leaking stock header at oxygen sensor (you can't remove it without fixating it's little adapter) and that went from 45 mpg to 31 and with oxygen sensor disconnected I am at 43 and that makes me wonder how important that was besides my probably dead by now oxygen sensor
 
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richardwbb said:
I a happy with what was just said, I happen to have a leaking stock header at oxygen sensor (you can't remove it without fixating it's little adapter) and that went from 45 mpg to 31 and with oxygen sensor disconnected I am at 43 and that makes me wonder how important that was besides my probably dead by now oxygen sensor
Click to expand...
Well an exhaust leak allows in oxygen, that the o2 sensor reads as running too lean so it adjusts fuel trims to compensate, adding more fuel, when you disconnected the o2 sensor it probably went back to it's safe values that are likely slightly rich as this safer than a lean mixture when the ECU has no feedback from the o2.
 
fuzzy-hair-man said:
The fuel map has rpm on one axis and load measured by the value from the MAF Mass Air Flow meter on the other axis. If you get a better air intake that is able to flow more air the MAF will read more air passing it, will therefore add more fuel and perhaps move load sites on the map.
If as I think you were trying to say it doesn't react to airflow then a dirty air filter would throw out the tune.
The o2 sensor effects short and long term fuel trims, this tries to account for anything else that might change over time, a good or bad batch of fuel, more ethanol, a MAF that's got dirty, etc.
Click to expand...
Actually load is a function of throttle body position, so wot equals to a line of values on the map. When you run megasqhirts ou det3, that's what determines the load of an engine.

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We are getting off topic but my ECU is a Nistuned factory ECU and the table holds the factory tune which I believe the original poster probably has, MS might work differently...
About your query, the ECU can perform a calculation to take the airflow and divide by rpm to get a figure like airflow / cylinder, this would distinguish a low load high rpm condition from a high load low rpm condition.
From: https://support.haltech.com/portal/en/kb/articles/mass-air-flow
Note that there are two units used with air flow and engine management. One is in Grams/Second (g/s) which reports the raw air flow measured by the sensor. The other is Grams/Cylinder which reports the proportional amount of air flow for the given RPM. If g/s were used for fuel mapping you would see air flow amount increase as RPM increases, whereas g/cyl produces a more usable scaling of air flow.
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OystonIsGone said:
Lots of replies on this, but still haven't got the answer to my original question

Will this airbox in the photos fit my 2002 k11 micra?

Thanks guys. I hope so as the seller needed me to decide so I bought it.

Sent from my SM-G960F using Micra Sports Club mobile app
Click to expand...
Sorry
The box will fit but the hole mounts will not align as well as the vent pipe for the pc.
Mine was just in place by the throttle body nothing else, actually I've cut the support holes of the primera box.
The intake pipe, not sure since I've used a 70mm custom pipe

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Jorge_EETC said:
Sorry
The box will fit but the hole mounts will not align as well as the vent pipe for the pc.
Mine was just in place by the throttle body nothing else, actually I've cut the support holes of the primera box.
The intake pipe, not sure since I've used a 70mm custom pipe

Enviado do meu MI 8 através do Tapatalk
Click to expand...
cool. thanks, do I need to do any other mod for this to work and give the slight improvement or do I just stick the Air box and intake pipe on?

If Intake pipe won't fit I will improvise with a few ideas from YouTube.
 
OystonIsGone said:
cool. thanks, do I need to do any other mod for this to work and give the slight improvement or do I just stick the Air box and intake pipe on?

If Intake pipe won't fit I will improvise with a few ideas from YouTube.
Click to expand...
The only other thing is the breather hose, it's the right diameter but too short.
Grab another hose with similar diameter and join them together with a smaller plastic tube.

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Jorge_EETC said:
The only other thing is the breather hose, it's the right diameter but too short.
Grab another hose with similar diameter and join them together with a smaller plastic tube.

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Click to expand...


Sorry totally a novice, which is there breather hose? Many thanks for your reply.
 
It's the small hose that connects the valve cover to the air box, it ventilates the built up pressure inside the engine

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Jorge_EETC said:
It's the small hose that connects the valve cover to the air box, it ventilates the built up pressure inside the engine

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Click to expand...


Think I got you. The underside of the airbox where it connects to the intake pipe where my current airbox is needs extending??


Thank you
 
Yes some contacts help but breakers will help you but then you will need to be sure how and what you ask. If you ask 1.6 primera filter you will get just that. Turn it around and ask precise so responder can't fail you or go for the show me some pictures route, this won't work well with most breakers though.
 

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