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Because I am not wholly convinced that AFM are the antichrist and MAP sensors are entirely awesome and because I am not across the detail of the Haltec and don't have a good understanding of the compromises involved in the two options as they relate to the ECU.

The air flow meter is unreliable and as they age, their readings change and change the tune as a result.

They are also slower to react to what the engine is doing as they measure the intake system filling up as well as what the engine is doing, making the throttle slower to react to your foot, as well as basic stuff like when they do die they are $300 each rather then 70 for a map

Oh and there's always they poor person stuck on the side of the road who blew and intercooler hose, cause a map doesn't care and will still be drivable

Well fair enough that is what you don't like about afm's but the question was about how they relate to the ECU that holds it back?

throttle response is a major difference and afms can throw the tune in the wrong cells with reversion, which was and still a major issue the pfc has

So you have fork out $300 every 10 years or so... not a great expense. to a certain point they are just as good as maps if the tuner knows what he is doing and there are a few around that do.

600 but even in your own words "to a certain point, they can be" but they usually aren't
  • Like 1

I think op wants afms so let him have afms. Otherwise all of this will turn into one big argument. A lot of us despise our afms. Especially when the solder joints crack or you have a boost leak or pop a intercooler pipe or the get oily and you have to clean them regularly.

Just keep the pfc. Why do you want to change it if you are not going map? Or eflex?....

I am almost certainly not but the main attraction of a current ECU is probably the ability to easily get data from it and log it in conjunction with a GPS data logger. Makes it easy to get such things as throttle %, rpm, or whatever else into the log without having to do it individually.

But like everyone says the PFC isn't the most refined thing in the world. Was brilliant in 1990, but it isn't 1990 anymore.

I think op wants afms so let him have afms. Otherwise all of this will turn into one big argument. A lot of us despise our afms. Especially when the solder joints crack or you have a boost leak or pop a intercooler pipe or the get oily and you have to clean them regularly.

Just keep the pfc. Why do you want to change it if you are not going map? Or eflex?....

I am the op not djr81

If getting rid of the AFM in preference of a map is recommended then I am all for it,

although I do not understand how it is an advantage if everybody says it is then I will believe them :P

If somebody wishes to explain then I would be grateful (I understand afm could be restriction to intake but I thought since map can only read pressure not flow it would be an advantage to have a AFM)

Jem are the ones initially suggesting I get the Haltec, but I am quite surprised that most people are in agreement I should ditch the PFC.

This could have been an expensive thread :/

I have a zeitronix zt2 wideband data logger for sale at the moment if all you want to do is log data.

250 bucks. Way cheaper than swapping ecu's, but also not as good as you can't log timing.

Edit: response was for djr81 not op.

As for op, it's a big outlay for minimal gains in my opinion.

Edited by Ben C34

Realistically what would I pay for the ECU and recommended sensors?

And what would I get for my PFC and Z32 AFM?

If it ends up costing me under $2k and I get launch control, flat shift, get to ditch the afm with support for e85 in the future as well as better resolution and logging then I am alright with the outlay, but are my expectations realistic?

The closest servo that sells e85 is over 500km away. E85 is not something I am willing to do, but if the ECU is compatible it is a bonus for future proofing my build. Would $2k be enough for Haltec after selling PFC? (Not including tune)

Basically the biggest thing you'll find when tuning a car is that a tuner needs as much accuracy as possible to tune the car. He's going to be pushing the motor pretty hard in some cases and if he can't fully trust the AFM this will definitely hold back the tune.


The other thing about these modern ECU's is that they have things like Long Term Fuel Trim, which essentially 'learns' where the ecu is running rich or lean when its being driven and then compensates for it. So if they are receiving incorrect signals about air, they will alter the tune and could become rubbish or your engine could show you a fireworks display, featuring pistons

Or you can look at it this way, your fitting a computer with 2014 technology in it and using technology designed in 1989 as your main load signal

Not exactly a fair point as most OEM management systems rely on AFMs. Doesn't matter what sort of AFM, so don't bother carrying on about flappy doors, vortex counters and all that. Hot wire AFMs are actually one of the better methods. Measuring load directly, as opposed to inferring it indirectly (by MAP) is actually a far more sound engineering practice.

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