Ashills dyno results.
- Thread starter Fusion Ed
- Start date
O
Odin
Guest
diesel weasel said:
You will be getting detention young man :shock: :lol: :lol: :lol: :lol: :lol: .
Now go an do a 100 lines of "I WILL STOP BEING A C0CK" ;-)
Rob
Fusion Ed
Active Member
Back on topic... I dont really see why an airflow meter should be all or nothing. Its true if you put a massive AFM on a car that flowed little amounts of air that much of the region would be within the lower voltages of the output, but scaled correctly this should not be that much of an issue. I would say that was more down to choice of turbo and ancillaries than afm.
Ed
Ed
O
Odin
Guest
I maybe way off base because i understand fook all about maf's never really ever having used one on my pulsar lol, But the Maxima is an N/A engine I believe so wouldn't the air going in be travelling a lot slower ?, So once you bolt it to a big boost pulsar the air speed going in is that much faster that Q45 is maxed out quite quickly ?.
Please feel free to slate my thoughts though
.
Rob
Please feel free to slate my thoughts though
.Rob
PaulB
Member
I dont agree with you there, its purely based on the volume of air, and the area of the 90mm Q45 MAF is far bigger than that of an 80mm Z32MAF, and therefore flows more air as a result.ashills said:
Il dig out some info i found when i was lookin at which maf to choose and put it up.
O
Odin
Guest
PaulB said:
But the Q45 is calibrated for an N/A engine and not a turbo, Surely that is the difference :? :? :? .
Rob
Fusion Ed
Active Member
To be honest this is all academic. The fact is without question that the Q45 is maxed out on Allens car at his current power level.
An airflow meter doesn't care what car its attached to. All it sees is airflow. It depends on the internal sensor and maf design as to how sensitive it is to air flow. The Q45 has a large flow area, this is important on a large capacity engine where any restriction on the intake will cause quiet a drop in power, so its designed not to be restrictive. This is not such an issue (although it of course still is equally valid) on a turbo motor. The only length of low pressure pipework is from the AFM to the turbo, everything after is under pressure, and so losses are not such an issue (its harder to get air from one place to another under vacuum than to force it in, hence why on cylinder heads the intake valves are larger than the exhaust.
Now just because it is so big does not mean the sensor is calibrated as such, and this appears to be the case. Make the sensor less sensitive and this AFM will do allot more power, physically its certainly no restriction.
An airflow meter doesn't care what car its attached to. All it sees is airflow. It depends on the internal sensor and maf design as to how sensitive it is to air flow. The Q45 has a large flow area, this is important on a large capacity engine where any restriction on the intake will cause quiet a drop in power, so its designed not to be restrictive. This is not such an issue (although it of course still is equally valid) on a turbo motor. The only length of low pressure pipework is from the AFM to the turbo, everything after is under pressure, and so losses are not such an issue (its harder to get air from one place to another under vacuum than to force it in, hence why on cylinder heads the intake valves are larger than the exhaust.
Now just because it is so big does not mean the sensor is calibrated as such, and this appears to be the case. Make the sensor less sensitive and this AFM will do allot more power, physically its certainly no restriction.
O
Odin
Guest
Micra Ed said:
All you needed to say was that I was right mate :doh: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: .
Rob
the nissan mafs are hotwire types, the wire is heated with an electric current, as the temp increases so does its resistance, in turn reducing the current flowing through the circuit, as air enters the intake and flows past the wire its is cooled, reducing its resistance allowing more current to flow which again increases its temperature and resistance until it reaches the point where the resistance is no longer increasing. The amount of current required to maintain resistance is in a direct relationship with the mass of air (not volume) flowing past the wire.PaulB said:
if the density of the air increases, due to changes in pressure or temperature the heat will be removed from the wire quicker which would appear to the maf circuit to be a higher mass of air.
the ciruit of the maf changes the current into a voltage which is what the ecu see's
The z32 maf, being off a turbo charged vehicle probably takes all of this into account with its calibration which is why the size difference in the q45 doesn't make much difference in its ability to measure a higher mass of air entering the engine..
possibly, maybe...i think...more to the point, maf sensors are for losers and you should all be looking at map sensors anyways these days, its is the year 2007 :lol: there is a standalone unit available now that will allow a map sensor to be used on an engine/ecu set up that normally uses a maf 8)
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Link?
http://www.maftpro.com/tproinfo.shtmlcampbellju said:
carlengerer
New Member
Keiron has a point about using map sensors instead of MAF.. there are pros and cons but the biggest indication that map is the way to go is that subaru has made the switch from maf to map sensors on their impreza. What I have heard is that they dont offer the same resolution (debatable) as maf but are more reliable.