TurboGuy

Less restriction? WTF are you smoking?

The air has to push a door open against a springin an AFM
MAF provides a clear flow path

Both can be restrictive depending on the application, but MAF is best for flow.

Toysrme

here's your problem. you're speaking with no experiance in the matter. what you think is some ungodly taught spring that is impossible to move.
you've never measured the pressure drop between a your typical 90mm maf and a large sized denso AFM have you? I did it years ago using the 3hp dust collector in the shop. the larger Denso AFM won. What you're missing is that MAF's have a gigantic *** tard of ---- impenging in the intake that's a disruption. where the AFM only overcomes the spring pressure, which is next to nothing in the first place.

I remember the difference on 300whp 3s-gte's between the large denso AFM and a tuned map being less than 3 hp and less than 1ft-lb of torque peak numbers. MAF'd & tuned looses more than either.

Hitchhikkr

No, this is your problem.

If you have never seen one seized, you dont work on cars. Besides, this isnt the problem with AFM's. Shitty resistors, and a physical potentiometer contact, are however.

Pressure drop and airflow through 2 different sized orifaces are completely apples and oranges. So you tested the pressure drop(pointless) of the afm and the maf with no synchrometer? Refer to my previous statements about how you are an idiot. Low-flow conditions (as with your imaginary experiment which I doubt you performed) are basically pointless in trying to determine high-velocity airflow restrictions. Basic fluid dynamics owns you.

If that tuner only extracted 3 more hp from a MAP setup as opposed to the afm, then he's one hell of a ****-poor tuner. There are also other variables to consider, like restrictions in the intake/exhaust, boost leaks, inconsistancy etc. Not to mention that you have totally and completely failed to produce anything in the way of evidence that supports your view.

Truely, the problem with the AFM doesnt lie in the fact that its a restriction (and it is) but it is limited in how much "airflow" (I use the term loosely here) it can see past a certain point.

Denso rip-off of the bosch LH-jetronic system, can only read to a certain airflow, ie when the flapper is fully open, the ecu recongizes this fact, and automatically follows its pre-programmed 'base' maps, which dont include provisions for anything other than stock boost/airflow. This applies to all vehicles running this type system. Stock car at stock boost under the right conditions can spike the meter open, but a mod. car with more airflow 'can' hold the meter fully open. Very bad for anything sensitive to VE changes, and worse for engines sensitive to detonation. This has been known for years, and is a real problem with 951's.

Not to mention your statement about the AFM's "never going bad" is completely wrong. MR2 Guru Has a box full of known dead AFM's that I have personally gone through and double checked myself.
They do go "bad", and you are an idiot.

I challenge you in your next post, to prove your point, to provide something other than your "opinion" (which at this point is worthless).
If you cant do that, I suggest you go out into the real world and gather some experience that doesnt include surfing internet forums.

jinxy

You are ------- smoking crack if you think an AFM flows more than a tube with a heated piece of wire in it.

Smith-02

afm's are great on a 22rte with stock everything.

after that, it's SS failboat arriving at port failvaria

jinxy

there are no ports in falvaria.

Toysrme

right now im jointing & planing a half grand worth of cabreuva (Santos Mahogany) to install in a guy's basement way . when im done with that (sometime this weekend or early next week) i will be more than happy to take a video of my spare second gen Denso AFM VS a dead Nissan MAF. i have to tear down the dust collector for a good cleaning when done anyway. It's going to be too full to work soon anyway.
btw... if you measure the pressure drop in the pipe before the unit at and after the unit at the cage housing it will directly corrilate to what is flowing through the entire pipework.
just for you i'll dispense with taking any pressure differense and come up with a way to see what's being output from the cage.



i said i never replaced a large denso one broken. that includes a time as a toyota tech, and many years since playing with the things. eletronic > electromechanical. yet for some reason with all these AFM's still in service from the late 80's & early 90's. We spent all day replacing broke *** MAF's from newer engines. between old S blocks two VZ blocks M blocks running AFM's VS mz's UZ's and JZ's with MAF's. the maf's got changed along more regularly over the same span of years.
The ONLY AFM I ever had to change the OWNER fucked it up by jabbing a knife blade into to top to adjust it and scored the board traces. Sure the resistive track will wear out. Just like eventually a hot wire MAF is going to burn out, short out or be so off-scale from such long periods of time subjected to the enviornment it lives in that its useless.

if nothing else. all the electronics of an AFM are sealed from the working enviornment and have no exposure to any moisture, or corrosive gas/fumes in the intake tract. In the late gen Denso intakes even the thermistor to measure intake temp is fully encased in a thin plastic of some kind.

Hitchhikkr

Physics still disagrees with your claims. We look forward to your pointless video.

This statement is under the ASSumption that the maf/afm is the most restrictive part of the system. Who cares about the IC pipe diameter, or the TB, or the airflow distribution between cylinders in the intake manifold...

And I said they break. You said they dont. You cant backpedal on the internetz yo!

Ive never met a toyota TECH. Those cars are SO simple I dont consider anyone who repairs them to be a TECH. You were a wrench turner/oil changer. By no means a tech.

At no point in this thread did anyone say anything about an MAF being more RELIABLE than an AFM. YOU said AFM has less pressure drop and therefore flows more than a MAF, which is incorrect. And since we are discussing toyota, the smallest MAF on the corolla still has a larger cross-sectional area than the 3sgte AFM.

What it really boils down to is that MAF/AFM is a cheap way for the OEM's to save money on the actual engine computer. I reference OBD1 Honda as my exhibit A in-point-of-fact for this statement. Speed density based, and 18 years later there are few standalones that rival the functionality of an OBD1 ectune'd ecu.

Your depth of experience is in question here. Not the assumption that since you were employed by toyota thats makes you an expert in all things with a T stamped in them. I personally know 3 toyota "techs" and none of them I would trust to change the oil on my AW11, or any of the eight toyota's I have owned in the last 6 years. Your credentials are invalid.

The "electronics" you refer to are nothing more than a poorly designed potentiometer and a few resistors.

TPS are of similar design, does that mean that since they are sealed from mositure/gas/hell/etc. that they cant 'go bad'

The thermistor is designed to be exposed to the elements. Its a negative temperature coefficient thermocouple. Folks commonly put them in their 200degree plus cooling systems. Why exactly does it matter if its encased in plastic?


We look forward to your future failure experiment. For the sake of scientific method, please post the experiment regardless of the results.

liam75

Opening up an AFM is a bad idea. People try it and claim it works, but from what ive seen its a waste of time. All you are trying to accomplish by messing with the AFM is giving the engine more fuel. Ive upped my fuel pressure with a rising rate fuel pressure regulator, which basically does the same thing. This is a band aid for a larger problem i know, but it works for me at the moment. I was surprised to find out how much fuel a 1.6L can use with a stock fuel system that’s being maxed out. Ive driven the car a fair bit and if i put it under boost too much it gets worse mileage then my V6 Dakota. That and it smells noticeably rich most of the time. I have retarded the timing 10 - 15 degrees from stock and am running 94. I know this is not the correct way to do it, but it works. For how long i dont know, but it works. Not that any of it matters since the car has a few other things that need sorting out so it will be parked until i get everything done properly.
As for the TVIS all the crap ive read and been told is saying the TVIS plates are closed with no vacuum, but that makes no sense. When i applied vacuum to the actuator the idle clears up and a noticeable difference in intake noise is heard like its sucking more air. That and it fixes my high rpm surge/lack of power. I tried just disconnecting the TVIS vacuum line and it made it worse.

And no my shift **** has not impregnated anyone yet, but thats only cause i dont use it very much.
Man that sounds lame.
The pictures of the car I have on the first page are the only other decent pictures I have right now. Ill see if I can take some more shots of the car this weekend.

Toysrme

your tvis issue check that your vaccuum tank holds vaccuum. when the check valve in them gets old they can leak easy when they see boost. new tank with a good check valvue wouldn't be doing that. only real issue with it should be openeing at the wrong time for the powerband (which they do anyway lol)

for alittle more fuel you just loosen the cog, adjust the by-pass screw / add external bypass as necessary.when you want a lot more fuel (like your na-t). larger injectors + medium fmu + tighter cog to try to reel them back in off boost. you can get plenty of fuel that way. where you run into trouble trying to get good driveability with it once the injectors get much larger than stock. afew years ago i did a sohc 3vz-e that would run open up great on a set of 315's out of a 7m-gte, run ok mid throttle off boost and not very well under that. had to swap the stock atmo regulator (had a 4:1 fmu-good fit for v6's) for one set in the low 20psi range (vs stock running 3-36'ish and 40+ @ WOT when the VSV opened it to the atmo). ran alot better after that. the original point was what you already know. if you wanna drive around before you get management to it. here's an easy way to cram fuel into it until whatever you wind up doing get's ready to roll.







hitchiker tell me about physics when your last name is plant heisenberg bohr, etc