So, my buddy has a 90' Miata and he was reading up on how he could adjust his AFM spring a few clicks and get A: Better gas mileage and B: A tiny bit of HP. So, I've been searching the past hour, and I have found a few posts on this, but each one has turned retarded. So, my question is, What exactly is the outcome of adjusting the spring strength? Honestly, I don't care about HP, just MPG.

So, I'm hopefully going to get a honest answer other then "Don't mess with it" or "Try it and tell us what happens." I do have a spare AFM handy if I mess anything up, so I don't need that advice either.

Thank you in advance.

 

NO.


-Ted

 

basically you shouldnt do it.

however, if you do try it, mark the thingee so you can put it back to stock.

you wont see any mpg gains in closed loop from this

 

Ok....I understand the reason why i shouldn't... And I know you have a very strong urge against doing it....But please, I've read enough of your responses in the other threads and you are seriously no help. I would like some feedback from anyone who has tried it and what happened(when done properly.)

 

Bump >.< plz

 

Nobody has tried it because there is a very high probability that you will totally screw up the AFM, making the car undrivable and possibly blowing the engine.

Adjusting the screw as you are talking about will make the car run leaner across the board. Assuming you get it perfect, it could help with gas mileage a bit, but more it is very hard to get it correct. If you really want better mileage, get a piggyback fuel controller like the Apex'i S-AFC. That way you can actually tune the fuel ratio's so you don't lean out the top end and blow the motor.

 

why would you want your AFM to incorrectly and unpredictably measure the air entering your engine improperly?

 

Look...use your brains for once.

How can you get better fuel mileage AND more power?
The AFM just measure (mass) air entering the engine.
If you start adjusting it, you're either telling the stock ECU that the engine is ingesting less air than it is (in which case it's leaning everything out), or you're telling the stock ECU that the engine is ingesting more air than it is (in which case it's richening everything out).
There's also a very good chance you're just **** it up, for which then you'd need to find a replacement unit.

Get an S-AFC is you wanna **** with fuel delivery, cause it's easier to install, easier to adjust, and less chances you'll **** something up.


-Ted

 

Oh, and you should read the stickies in this section, cause this **** isn't allowed in here...


-Ted

 

Actually Miatas use the S4 AAFM as an upgrade and they use it for some basic tuning too. Check www.miata.net for info. By leaning out the notoriously rich mixture you should be able to get better milage and power.

Be careful though.

 

Playing around with the afm spring tension also effects TIMING. The afm is a Large player as far as advancing/retarding timing (HENRIK)goes I'd recommend not doing this and if you do, only moving a tooth one way or the other plus KNOWING exactly where you started in the first place. NOT as easy to figure as you might think. Plus you have no way of telling what happened once you did this that or the other unless you have a way of logging the afr etc.

 

i do it on all my 22re toyota's always mark where stock is and only go a few clicks at a time (get a wideband O2 to check your a/f) ive got a spare AFM i'm messing with on a stock 88 i'll let you know how it goes.


some good info on the mod for a 22re

http://www.4x4wire.com/toyota/minutemods/afm/

 

it seems really ghetto to do this to an AFM when you can also adjust the airflow signal much more precisely by using an oldschool original SAFC which are like $100 on ebay or something