Air flow meter idea
#1
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Air flow meter idea
wassup,
i know there's been a lot of talk about the air flow meter being the most restrictive part of the intake which got me wondering. . .
here in Canada Mazda produced a the MX3 a.k.a. the Mazda Precidia. this car might also have been sold in the states but not sure. Anyways from '92-up these cars come with a nice big round style air flow meter which definitely seems to be a lot less restrictive than the stock flapper. I was just wondering if any one knows how hand it would be to swap one of these into an RX7 if it's even possible????
Just something to think about!!
i know there's been a lot of talk about the air flow meter being the most restrictive part of the intake which got me wondering. . .
here in Canada Mazda produced a the MX3 a.k.a. the Mazda Precidia. this car might also have been sold in the states but not sure. Anyways from '92-up these cars come with a nice big round style air flow meter which definitely seems to be a lot less restrictive than the stock flapper. I was just wondering if any one knows how hand it would be to swap one of these into an RX7 if it's even possible????
Just something to think about!!
#3
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ok, the cone AFM looks to be more restrictive than the flapper bc the cone is actually IN the intake path and doesn't open, it just moves in and out. the flapper AFM looks like the superior one for flow, the question is how is the cone AFM programmed...does it run the car leaner than the flapper?
#5
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The flapper type was used for quite a few years on the Miata, and a common upgrade is to use the FC S4 flapper on the Miata.
The Miata and the base/mid range MX3 used the same 4 cyl, but the Miata always had more HP.
It would seem to be going the opposite direction to use the cone type.
And the flapper type found on the FC was typically not a restriction to the air flow until you got around 350HP.
Remember the big reason for Mazda to switch from a Flapper type (S4 cars) to the cone type found on the S5 cars was that the cone was cheaper to build and more forgiving on installation. It was not a source of additional HP.
The Miata and the base/mid range MX3 used the same 4 cyl, but the Miata always had more HP.
It would seem to be going the opposite direction to use the cone type.
And the flapper type found on the FC was typically not a restriction to the air flow until you got around 350HP.
Remember the big reason for Mazda to switch from a Flapper type (S4 cars) to the cone type found on the S5 cars was that the cone was cheaper to build and more forgiving on installation. It was not a source of additional HP.
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there was a thread awhile back that was saying the exact opposite of whats being said here. they said that the cone style was less restrictive. and i hope that it is cause i wana install that on my 87 T2 so i can just put on a cone filter with out an adapter
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#10
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Originally posted by mazemaster
Try this:
Try this:
#11
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For this mod, besides aquiring the S5 afm, you also have to have the connector for it since the S4 connector is not used.
The diagram displays how the wiring relates from the S5 connector to the S4 connector and as such is connected to your existing harness.
If you are still having problems reading the diagram, I would highly suggest getting someone who understands it to help you out when doing this mod.
PS: Also when converting to the S5 afm, the fuel pump cutoff protection is eliminated.
The diagram displays how the wiring relates from the S5 connector to the S4 connector and as such is connected to your existing harness.
If you are still having problems reading the diagram, I would highly suggest getting someone who understands it to help you out when doing this mod.
PS: Also when converting to the S5 afm, the fuel pump cutoff protection is eliminated.
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Originally posted by mazemaster
For this mod, besides aquiring the S5 afm, you also have to have the connector for it since the S4 connector is not used.
The diagram displays how the wiring relates from the S5 connector to the S4 connector and as such is connected to your existing harness.
If you are still having problems reading the diagram, I would highly suggest getting someone who understands it to help you out when doing this mod.
PS: Also when converting to the S5 afm, the fuel pump cutoff protection is eliminated.
For this mod, besides aquiring the S5 afm, you also have to have the connector for it since the S4 connector is not used.
The diagram displays how the wiring relates from the S5 connector to the S4 connector and as such is connected to your existing harness.
If you are still having problems reading the diagram, I would highly suggest getting someone who understands it to help you out when doing this mod.
PS: Also when converting to the S5 afm, the fuel pump cutoff protection is eliminated.
#14
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Is there a way to mod the s5 afm?
Like drill holes in it or maybe enlarge the diameter or the entire thing?
I'm probably doing to get flamed for this, but oh well..
Like drill holes in it or maybe enlarge the diameter or the entire thing?
I'm probably doing to get flamed for this, but oh well..
#15
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And you'll need an S-AFC to tune your fuel curve afterwards...
Really, AFM "upgrades" are not worth it on stock or nearly stock cars. And by the time you get to the point where the AFM becomes a restriction, you should have a stan alone system anyway...There are PLENTY of 400HP+ FCs in Japan running the stock AFM...
Really, AFM "upgrades" are not worth it on stock or nearly stock cars. And by the time you get to the point where the AFM becomes a restriction, you should have a stan alone system anyway...There are PLENTY of 400HP+ FCs in Japan running the stock AFM...
#17
I've never been a believer in removing the AFM, or modifying it. I don't think it will make enough horsepower to be worth it at all. I will increase throttle response.
It's been said a million times. If you want to get rid of the AFM go standalone.
It's been said a million times. If you want to get rid of the AFM go standalone.
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Not get rid of the afm but maybe modify it so it can be less restrictive. Or is there a way you can take an afm from some newer cars and correct the electrical signal with resistors?
#19
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Originally posted by 88IntegraLS
How much more airflow is the S4 turbo AFM cabable of metering vs. the NA meter?
How much more airflow is the S4 turbo AFM cabable of metering vs. the NA meter?
mike
#20
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Originally posted by Pinfield357
...they said that the cone style was less restrictive.
...they said that the cone style was less restrictive.
If you 're going to go to the hassle of swapping in a different AFM, it needs to be something significantly better than stock to provide a worthwhile or even noticable difference.
Last edited by NZConvertible; 11-01-03 at 03:27 PM.
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What if we can find a sensor that isn't a flap type or cone type. I think newer sensors are way less restrictive than the ones we have on our rx-7. The s5 one has an inlet of 2.5" and the rest of the tubing is 3". It just doesn't make sense to me.
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something like this
http://www.jdsperformance.com/index....tem&inmake=all
The advantage is probably not worth the price but I'm pretty sure some newer cars have this kind of sensor built in them. So maybe we can just get one from the junker for a good price and we might have a decent mod.
http://www.jdsperformance.com/index....tem&inmake=all
The advantage is probably not worth the price but I'm pretty sure some newer cars have this kind of sensor built in them. So maybe we can just get one from the junker for a good price and we might have a decent mod.
#23
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You cannot use a hotwire MAF sensor on cars that came with a vane or cone AFM. The output is completely different and requires complex electronics to make it work.
Any drop-in swap must be a bigger version of what we already have.
The only AFM I know of that might be swappable (with a fuel computer to tune it) is the cone-style AFM fitted to the JC Comso (13B and 20B). I've never seen it done though.
Any drop-in swap must be a bigger version of what we already have.
The only AFM I know of that might be swappable (with a fuel computer to tune it) is the cone-style AFM fitted to the JC Comso (13B and 20B). I've never seen it done though.
Last edited by NZConvertible; 11-01-03 at 08:21 PM.
#24
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The AFM doesn't create as much restriction as you think. The main performance advantages of going to a standalone are:
1) AFR may be tuned for better performance and fuel economy.
2) The faster standalone ECU is far superior to the slow stock ECU (especially vs the incredibly slow S4 ECU).
3) Ignition timing may be optimized for performance.
Getting rid of the AFM restriction does help some, but it's a very minor amount, and is certainly not worth worrying about or spending lots of time and money "fixing". When you hear the standalone EMS proponents (myself included) talking about getting rid of the restrictive AFM, you need to understand that this is just an added plus, and not the main purpose of a standalone EMS. Getting rid of the stock ECU is the main purpose of the standalone EMS. Those of you who build your whole life around getting rid of the AFM but still running the stock ECU are really missing the boat on this one.
I would also like to point out that a standalone EMS does not necessarily mean a speed-density (MAP and rpm sensing) system. Depending on the brand and model of EMS, it may also work in Alpha-N mode (TPS and rpm sensing), or even work in mass airflow mode with the stock AFM, aftermarket AFM, or aftermarket MAF. Yes, that's right, some standalones use AFM's. This is because the mass airflow system will stay in tune with minor changes in the engine due to wear, break-in, deposits, etc., which is why auto manufacturers choose this method of management for their street cars.
1) AFR may be tuned for better performance and fuel economy.
2) The faster standalone ECU is far superior to the slow stock ECU (especially vs the incredibly slow S4 ECU).
3) Ignition timing may be optimized for performance.
Getting rid of the AFM restriction does help some, but it's a very minor amount, and is certainly not worth worrying about or spending lots of time and money "fixing". When you hear the standalone EMS proponents (myself included) talking about getting rid of the restrictive AFM, you need to understand that this is just an added plus, and not the main purpose of a standalone EMS. Getting rid of the stock ECU is the main purpose of the standalone EMS. Those of you who build your whole life around getting rid of the AFM but still running the stock ECU are really missing the boat on this one.
I would also like to point out that a standalone EMS does not necessarily mean a speed-density (MAP and rpm sensing) system. Depending on the brand and model of EMS, it may also work in Alpha-N mode (TPS and rpm sensing), or even work in mass airflow mode with the stock AFM, aftermarket AFM, or aftermarket MAF. Yes, that's right, some standalones use AFM's. This is because the mass airflow system will stay in tune with minor changes in the engine due to wear, break-in, deposits, etc., which is why auto manufacturers choose this method of management for their street cars.
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Originally posted by Evil Aviator
The AFM doesn't create as much restriction as you think. The main performance advantages of going to a standalone are:
1) AFR may be tuned for better performance and fuel economy.
2) The faster standalone ECU is far superior to the slow stock ECU (especially vs the incredibly slow S4 ECU).
3) Ignition timing may be optimized for performance.
Getting rid of the AFM restriction does help some, but it's a very minor amount, and is certainly not worth worrying about or spending lots of time and money "fixing". When you hear the standalone EMS proponents (myself included) talking about getting rid of the restrictive AFM, you need to understand that this is just an added plus, and not the main purpose of a standalone EMS. Getting rid of the stock ECU is the main purpose of the standalone EMS. Those of you who build your whole life around getting rid of the AFM but still running the stock ECU are really missing the boat on this one.
I would also like to point out that a standalone EMS does not necessarily mean a speed-density (MAP and rpm sensing) system. Depending on the brand and model of EMS, it may also work in Alpha-N mode (TPS and rpm sensing), or even work in mass airflow mode with the stock AFM, aftermarket AFM, or aftermarket MAF. Yes, that's right, some standalones use AFM's. This is because the mass airflow system will stay in tune with minor changes in the engine due to wear, break-in, deposits, etc., which is why auto manufacturers choose this method of management for their street cars.
The AFM doesn't create as much restriction as you think. The main performance advantages of going to a standalone are:
1) AFR may be tuned for better performance and fuel economy.
2) The faster standalone ECU is far superior to the slow stock ECU (especially vs the incredibly slow S4 ECU).
3) Ignition timing may be optimized for performance.
Getting rid of the AFM restriction does help some, but it's a very minor amount, and is certainly not worth worrying about or spending lots of time and money "fixing". When you hear the standalone EMS proponents (myself included) talking about getting rid of the restrictive AFM, you need to understand that this is just an added plus, and not the main purpose of a standalone EMS. Getting rid of the stock ECU is the main purpose of the standalone EMS. Those of you who build your whole life around getting rid of the AFM but still running the stock ECU are really missing the boat on this one.
I would also like to point out that a standalone EMS does not necessarily mean a speed-density (MAP and rpm sensing) system. Depending on the brand and model of EMS, it may also work in Alpha-N mode (TPS and rpm sensing), or even work in mass airflow mode with the stock AFM, aftermarket AFM, or aftermarket MAF. Yes, that's right, some standalones use AFM's. This is because the mass airflow system will stay in tune with minor changes in the engine due to wear, break-in, deposits, etc., which is why auto manufacturers choose this method of management for their street cars.
alpha n is hard to get driving, we have tried both ways on the same car and the map style runs smoother
mike