So long asthmatic AFM

[Blitzkrieg Bob]

Well, its been a week since I converted my M20 powered 525 to the Miller MAF system.

All I can say is.......Smoooth. The car is a little perkier, more responsive and so far seems to be getting better MPG.

http://www.millerperformancecars.com/catalogue.html?page=shop.product_details&flypage=flypage.tpl&product_id=58&category_id=6

[Sixdown]

Glad you like it. I keep telling myself to get one but can't bring myself to putting down the money...

[Blitzkrieg Bob]

Glad you like it. I keep telling myself to get one but can't bring myself to putting down the money...

Ask PCP JR about his 535 kit........He swayed me.

[BigKriss]

well, show us some pictures Bob.

[e34.535i.sport]

Well, its been a week since I converted my M20 powered 525 to the Miller MAF system.

All I can say is.......Smoooth. The car is a little perkier, more responsive and so far seems to be getting better MPG.

http://www.millerperformancecars.com/catalogue.html?page=shop.product_details&flypage=flypage.tpl&product_id=58&category_id=6

I'm jealous! :D I would love to give it a go but with shipping/duty/tax bringing it over to the uk seems a bit too expensive :(

[Blitzkrieg Bob]

well, show us some pictures Bob.

Here's what i looks like before the install

[genphreak]

I've had one for almost 2 years now. Best thing you can do for an M30 next to a Megasquirt which costs waaay more time and effort. Optimum performance and economy to help pay for itself. If you haven't got a chip, stop eating for however long it takes to save up, and buy one. This black Miller **** is gold for our cars... LOL

[dennyg]

I am interested in the performance and reliability of the MAF kit in cold weather and all around situations. I will buy one of these if those who have tried it before me can attest to there being no side effects. Or hard starting issues. Thanks

[Blitzkrieg Bob]

I am interested in the performance and reliability of the MAF kit in cold weather and all around situations. I will buy one of these if those who have tried it before me can attest to there being no side effects. Or hard starting issues. Thanks

The two installs I know of are both here in Hawaii, so we never have any cold start problems.

[Claude]

I've had one for almost 2 years now. Best thing you can do for an M30 next to a Megasquirt which costs waaay more time and effort. Optimum performance and economy to help pay for itself. If you haven't got a chip, stop eating for however long it takes to save up, and buy one. This black Miller **** is gold for our cars... LOL

So could you explain a bit more what's the main PLUS of this MAF compare to the original one ? How different is the technology and the performance that may justify the investment cost ?

[Blitzkrieg Bob]

So could you explain a bit more what's the main PLUS of this MAF compare to the original one ? How different is the technology and the performance that may justify the investment cost ?

The original AFM system used a spring loaded pivoting flap hooked up to a potentiometer to measure the flow of air. As the throttle is opened and more air is required, the flap is forced open by the intake of air.

The MAF system uses a heated wire or film to measure the flow of air. As the throttle is opened and more air is required, the heat wire/film is cooled by the intake of air and metered.


The benefit is that the obstruction of the AFM flap is removed from the intake along with all the mechanical parts as well, and replaced by an MAF sensor mounted in a tube.

Plus you get a new chip that also helps out performance.

[genphreak]

On ya BB!

Also, the MAF gives a stable output, the AFM attempts this with a variable resistor, and once the PCB tracks get worn, it gives a spikey output that cases the ECU to make incorrect decisions about timing and fuel, and makes the car run erraitcally in some conditions- ie heat, throttle position, all affect it etc.

The MAF makes the most difference on a car with a worn AFM. I don't think many wouln't be these days. Its worth measuring the output of your AFM with a multimeter and by moving the flap with your finger, evenly. If the output spikes, change it else it'll waste fuel the longer you stiock with it.

Also, using a MAF saves 2lbs weight up high in the engine bay... LOL :)

I live in a temperate climate, haven't seen any problems with ambient heat, but here we're above 10 degrees Celcius even in Winter...

[Claude]

The original AFM system used a spring loaded pivoting flap hooked up to a potentiometer to measure the flow of air. As the throttle is opened and more air is required, the flap is forced open by the intake of air.

The MAF system uses a heated wire or film to measure the flow of air. As the throttle is opened and more air is required, the heat wire/film is cooled by the intake of air and metered.


The benefit is that the obstruction of the AFM flap is removed from the intake along with all the mechanical parts as well, and replaced by an MAF sensor mounted in a tube.

Plus you get a new chip that also helps out performance.

Make sense, after technlogie upgrade after 20 years.
Does the new chip optional or a must to interface the new MAF ?
Why should we be concern about efficiency of this MAF in very low temperature (-20, 30 C) ?

Thanks for your explanations.

[Jeff N.]

The biggest issue with the MAF conversion is the air temp correction. This is the primary reason the Miller kit comes with a new chip. It has nothing to do with performance and everything to do with air temp correction.

The AFM unit measures 'air flow' via a mechanical device and then applies a fueling correction based on the intake air temp to determine the correct volume. Colder air = more volume = more fuel. This is managed via an offset table for the fueling function in the DME.

A hot wire MAF is sensitive to ambient air temp changes via it's normal process. (ie: the same airflow at a colder temp generates a different output voltage than at a warmer air temp) and thus the stock chip's correction table is off.

Additionally, the chip on the miller unit corrects the fueling voltage translation from the MAF voltage. (the MAF output does not directly correlate to the AFM voltage as the same airflow.

For the miller unit to work, you must have their chip. It's primary function is to account the changes with the MAF sensor. Unclear to me what if anything they have done with performance tuning with the chip (ala a Mark D chip).

I have a MAF conversion but I do all the corrections with a Perfect Power SMT-6 unit.

[Blitzkrieg Bob]

Unclear to me what if anything they have done with performance tuning with the chip (ala a Mark D chip).

I was waiing for Mark's MAF conversion kit. But he decided to shelf the project.

So, I went for the Miller kit.

The Miller chip is supposed to also have performance tuning too, thus the change to 92 octane. But on my M20 the gains appear to be rather mild.

They also have a new chip that has a mini USB port to allow remote flashes via email down loads for advanced tuning.

[Claude]

Well, its been a week since I converted my M20 powered 525 to the Miller MAF system.

All I can say is.......Smoooth. The car is a little perkier, more responsive and so far seems to be getting better MPG.

http://www.millerperformancecars.com/catalogue.html?page=shop.product_details&flypage=flypage.tpl&product_id=58&category_id=6

Someboddy have a picture showing what a Miller MAF system look like on a 535 E34 in place of the original one ?

[genphreak]

Make sense, after technlogie upgrade after 20 years.
Does the new chip optional or a must to interface the new MAF ?
Why should we be concern about efficiency of this MAF in very low temperature (-20, 30 C) ?

Thanks for your explanations.

Yep the new chip contains adjusted mapping for the 12V operation of the MAF. The AFM provides a 0-5V return signal only.

[Blitzkrieg Bob]

Someboddy have a picture showing what a Miller MAF system look like on a 535 E34 in place of the original one ?

Here it is

[Claude]

Here's what i looks like before the install

Why do you show this motronic box beside the MAF, did you had to replace the original also ? Mentioned elsewhere that only a new chip is needed with the Miller...

[Blitzkrieg Bob]

Why do you show this motronic box beside the MAF, did you had to replace the original also ? Mentioned elsewhere that only a new chip is needed with the Miller...

I had a spare DME, so I put the chip in before the install to speed things up.

[e34.535i.sport]

I've had one for almost 2 years now. Best thing you can do for an M30 next to a Megasquirt which costs waaay more time and effort. Optimum performance and economy to help pay for itself. If you haven't got a chip, stop eating for however long it takes to save up, and buy one. This black Miller **** is gold for our cars... LOL

HI! Glad I read this post... Can I ask if your car has a CAT? I emailed the guy over the cinversion and he wasnt too sure about the suitability for my euro spec non-CAT 535, as I had trouble with an EAT chip I tried - It threw the o2 sensor code (When it doesn't even have one LOL) and I'd need to be sure its suitable before proceeding... Thanks!

[///Sniper535]

did you need the adapter to connect to the factory airbox?

[M20Turbo]

Here's what i looks like before the install

Do you have a pic of it installed?

[factus6]

I had the Jim Conforti chip from Turner since 1999 when I bought my 91' 535iM and it gave the car how I would describe as a real sense of urgency when punched. I just put the Miller MAF Gen III in a month ago and I would never go back, the MAF definitely gives the M30 more low end and midrange power which is perfect for my driving conditions I rarely punch it anymore since the drivers and traffic has gotten much worse here in Austin Tx. I had a bad AFM for 10 years and did not realize it was causing a really bad cold start problem in the winter and a rough idle with an edge to it and oscillations that drove me nuts during all seasons. I could only smooth it out by opening the valves a bit, and the plug gap for some reason. Currently my valve adjustment is at spec and with the MAF the idle has smoothed out, now it is much more comfortable sitting at stoplights. However it does idle rough when cold, I have heard others complain of this same issue with the Miller MAF, but it warms up quickly and runs so much better than before I can live with that.

Here is a pic of my install.

http://dl.dropbox.com/u/1770548/Miller.JPG

[genphreak]

HI! Glad I read this post... Can I ask if your car has a CAT? I emailed the guy over the cinversion and he wasnt too sure about the suitability for my euro spec non-CAT 535, as I had trouble with an EAT chip I tried - It threw the o2 sensor code (When it doesn't even have one LOL) and I'd need to be sure its suitable before proceeding... Thanks!

Yep, my cars are euro spec 'katalyst' models. Never had an 02 warning- IMH experience this is due to other things usually vacuum leaks- or a faulty 02 sensor, which is a wear item, $50 odd and easy to change. 5-10 years is a good period to change them out but the longer you leave them once they go out of spec, the more fuel you waste anyhow so its worth changing before they get bad enough to throw errors.

Your car's chip will have no effect on whether you get an 02 sensor error, assuming its a good one, and Mark Ds are nothing short of stunningly excellent (but cannot be used with a Miller MAF conversion)

[Tiger]

Miller MAF seems to be limited to 6 cylinders only

[genphreak]

@Tiger, They are working on M60s I believe, best to ask them if u need one- I guess there is less demand as they come std with them of course.
@BB, That's a nice looking example of a state of the art M30B35 u have there now... :-)

[rob101]

slightly OT but Nick can you empty your PM box I tried to send you a PM but no joy. Nice to see Bimmer.info is still alive and kicking!

[myles]

Welcome back rob!

[rob101]

Hi All