MAF swap
 

I know about the rx7 MAF swap, but has anybody else swaped a diferant MAF into their miata. I was looking at a 4.0 ford MAF.

why?

What's wrong with the one you have?

no. just no. I already banned someone today for quality control...

All MAF's suck... and they are expensive.... no one MAF or AFM is less sucktastic than another. Stick with suck, or unsuck it with MS

yeah that's so 2005-2008 ago. It's no longer acceptable to maf/afm.

If my research is correct the RX7 swap is because the AFM has the same response curve as the miata's AFM, and since it's larger, it sucks less. I wouldn't think you could just drop a random MAF in and expect the OE ECU to be able to use it. Especially since the AFM's run 5-0v vs. 0-5v of the normal MAF sensor.

In a turbo miata, I wouldn't look twice at anything other than Speed Density, but riddle me this, why does MAF suck for a non turbo motor? And if it sucks so much why does basically every manufacturer use it?


For the record, I'm running SD on mine, but considering MAF if/when I go to individual throttles and big cams.

every manufacturer USED to use them frequenly...... not seen so much now. and if they DO have them, its usually the heated wire style MAF, rather than the "flapper box" style AFM. I havent seen a flapper box style in a while.... I also do NOT claim to have seen the engine compartment of every car ever either... so maybe some still DO use them. IDK. haha

I'm pretty sure most still do. The only ones I could find that DON'T are the new ecoboost and the Hemi. Dodge does have a history of using speed density.

Agreed on the AFM/flapper boxes. They're LONG gone. But MS and most to all aftermarket ECUs will run a hot wire MAF.

I know MT's groupthink is that MAF's are bad and SD is the only way to go, but I'm just not convinced this is 100% for 100% of miatas.

How does a MAF work with ITB's??? Ive always seen ITB's with just a bell style intake mounted to the throttle body on each cylinder

You need a real, pressure tight housing over the bellmouths.

Ah... onkie donkie... dont know much about ITBs... think they look cool, but never got how they measured airflow

Its not.

Our groupthink is that on a boosted miata, a popular EMS using speed density is a relatively straightforward, effective, and efficient way to go.

Many OEM's still use a maf, but they are much more advanced than our 80's technology BP electronics.

I can't argue with that, though if you're boosted you shouldn't be on 80's electronics.

I guess that's what I/we/you get for having a MUCH better signal to noise ratio vs. CR or m.net. The occasional oddball like me, ski_lover and hingstonwm shows up.

Hot wire MAFs are awesome. I love hot wire MAFs. The effort to reward ratio for putting a good GM maf into a car that didnt have one is too high for me. It lets me have marginally more accurate fueling and spark but requires extra wiring and more time devoted to dialing in transient fueling, and none of the affordable tuning options support transient spark which is kind of important to have in a maf car.

From what Ive read their is a little to gain on the top end with a larger MAF over the stock on my 97 as the flow of the stock is limited due to the size. The MAF is a hot wire as is the ford version. This car is a track toy and spends most of its time 4k-7k rpm so anything I can do to help the top end is a good thing. I am not afraid to experiment so if their is any merit to the idea at all I will give it a shot. One day Ill probably just swap a v6 in it but till then Ill experiment and have fun doing it. If it wasn't fun I would find something different to do. Im not a purest and love the thought of cheap grassroots upgrades.

me?
 

Is this directed at me?

Do be aware that different MAFs have different CFM/v curves. Does your car have an aftermarket ECU? With the stock ECU you'll either be rich or lean all the time. I seriously doubt the car will be happy with a nonstock MAF.

Currently the ecu is stock but I have been shopping for a picky back fuel management with wideband like that from AEM.

why piggyback?

toss the shit ECU and the shit MAF.

ECU
 

Agreed, but it is $750 plus for a mega squirt and wife says no at this time in our financials :(

I mean you're talking about spending money to MAYBE make 1rwhp...

if you're too poor to modify cars, or your wife wears the pants in the relationship, don't modify cars.

Im having fun and that's all that counts. Please don't insult me as my wife and I (and 4 kids) live in the real world and my car is a toy.

$750 is too much, you are right. Instead why don't you spend $500 on a piggyback and $200 on a MSD box. It'll totally be worth saving that $50. Except your car will still suck.

I live in the real world too. Except I choose to not have a wife and kids and modify my car.

If I wanted to insult you, I would have said a whole lot of other things, trust me.

I'm not insulting you, I'm telling you the blatant truth. Lots of people get offended over it because the truth is not always pleasant to hear.

If by "having fun" you mean making terrible decisions and wasting tons of LITTLE amounts of money here and there that all add up in the end to equal a large chunk of change, sure thing: have fun with your car. The end result will be mediocrity and wasted money and effort, but at least you had "fun" along the way right? lol

You're not the 1st, or even the 100000th person to have this mentality.

I still don't see why you want to spend money on something that will help so very very little. But only cause you a headache, and the runaround.

Wow, rain on my parade a little more please. If you want to paint your car pink and have purple spinners do so. Its your car. If your only here to criticize ... please ignore me. If I have these questions then Im sure others have them too. Soooo, I will experiment and learn, ask for advise when I must and share info as I get it.

@ 18psi
Anybody can modify "their" car even if the "mods" dont make any sense. As far as "wearing pants in the family". Like any "good" marrige ... we share a leg. Please keep the advise to cars and not my personal life.

All this is off topic ... sorry about the rant.

<notes OP's location>
<notes OP's model year>

Yep, that blows. My recommendation is if you're going to go messing with your engine, ditch the 97 and go with an OBDI car if you want to play with the motor.

Why don't you put that $$ into your suspension? It'll be much more rewarding in my opinion. I'm also of the opinion that you're tilting at windmills with the MAF swap. Sorry, I just think you won't end up with the result you're looking for.

You might hate us now, but you'll hate yourself more if you bother with the time/$$$ investment of a larger MAF to maybe try to squeeze 1hp out of it.

We are saving you from yourself.

Who's criticizing?

We've been trying to figure out your logic for a while now.

If you want to paint your car purple, or pink, most of the people here can understand that's a personal thing. You like it because of the way it looks.
Do you have something against the OEM MAF? Has it treated you poorly? Do you have a thing for the Ford MAFs? What is it? Do you want to change it based on it's looks?

I think only people with mental health problems(maybe others here too) do things that cost them money for no return. (CR is good at doing this, not us)

:laugh:

I'm glad she makes you feel like you both share a leg. That's the key.

The difference between this site and others is we'll tell you straight up if you ask a stupid question or have a terrible idea.

vs

Other sites will hold your hand, coddle you, spoon feed you, and generally make you feel good about your terrible decisions at the time you're making them. Then you realize the truth after the fact.


By all means paint your car purple and put spinners on it. Its your midlife crisis, make the best of it.

Fuck you OP. We will criticize who we want. Don't want criticism? Don't post.

We aren't going to hold your hand and tell you your farts smell good while you do stupid shit. If you can't handle that there's the door.

Love you guys too, thanks for the help.
Good advise for the most part, time to save the exspensive stuff. So which engine mods shall I save for first?

Besides megasquirt?

It depends on what you want to do with the car. You plan on turbo'ing it eventually?

The ones you were about to read about in peoples build threads instead of asking dumb questions.

Seriously stop asking dumb questions and go read build threads. You will learn a lot more.

The only dumb question is the one not asked for fear of ridicule.

I am a newb but I refuse to believe that all mods have been tried. Sure, there is a generic tried and true method to everything we do. I just like to explore other options so I ask folks like you who have alot more experiance and knowledge in the area. From the good and bad responses I have recieved I know I can put the idea to rest.

No, I do not plan on a turbo. My plan ... one day ... if it will fit ... is the 3.7v6 out the current mustang. The whole motor only weighs 20lbs more than the 1.8, but that will be after my 1.8 fails or I kill it trying to do some DUMB mod that I didnt ask question about.

good luck bro. I'm in sadomasochism and self-loathing too.

No, the ones asked because you are too lazy to search are also dumb. You know they are dumb questions because when you find the answer you will feel dumb for asking it.

How could you possibly know what has been tried and what hasn't if you haven't read anything?

You don't even plan on doing engine swaps the correct way. Everything you want to do is half-assed.

Piggyback and Maf swap to get almost-kindof-sortof-not-really to a standalone...

Motor swap that's missing two cylinders...

Racelands instead of a suspension worth a fuck...

Please kill this thread as my feeling are so hurt I will simply burry my head in the sand, sell my miata and jump off a cliff. Oh wait, just kill the thread please.

Help me help you.

No intentions of going turbo.

Joins Miataturbo for advice.


https://www.miataturbo.net/attachmen...ine=1374606976

Too soon?

Welcome to miataturbo, the only car forum where "haters gonna hate" is not a valid argument!

#1 all time hater award will forever goto Scott. He is my hero. He hates even when he doesn't mean to hate.

I hate you for hating.

Somewhere in the world Scott is hating on something/someone right now.

Even 1.8 MAF is excrement. I gained 5rwhp just by removing it, and that's N/A

That's nothing. I gained 10RWHP just by excrementing into my MAF. :party:

'cause the 1.6 didn't have a MAF. It had an AFM. Different principles, different response curves. Also there are loads better hotwire MAFs out there than the 1.8NA's.

Can you list a few?

*disclaimer: I agree with the trend in this thread, waste of effort and money. Get megasquirt or mod your suspension.

That being said, all the brokedicks in the protege/323/escort world "think" it is beneficial to swap the electronics out of the stock vaf(flapper box) into a vaf with a larger body. Typically from the F2/F2t powered mx6 or probes. Look up k-code hybrid for more. IMHO, any "gains" will only exist in your head.

Edit: didn't realize op had an obd-II car.

The NA 1.8 MAF is pretty restrictive, but the NB one isn't too bad.

MAF vs Speed/Density -- in principle, MAF should be better. Instead of baking the VE of the motor into a 3d table so that you can extrapolate from MAP & RPM into a fuel amount, you just directly measure the air going in. As for why it's not more prevalent in the aftermarket, most of the downsides to Speed/Density come from a comparative lack of flexibility in dealing with changes to the motor's VE. With a factory computer that sucks because if you put a better-flowing exhaust on the engine, then suddenly the fueling is all wrong and you can't fix it. With an aftermarket computer it's still wrong, except you have a wideband so the computer can cope and then you just fix it. So S/D is cheaper and easier and doesn't have a major downside, so why use MAF?

People who tune cars with reprogrammable factory computers and factory MAF sensors often stick with the MAF sensor.

--Ian

OP has a 97, so he's got a hot wire, not a flapper door.

That said, swapping to the Rx-7 flapper door on the 1.6 cars is one of the commonly accepted cheap small hp mods. Sure it was only worth a few hp, but the Rx-7 sensors were cheap and easy to get. Doesn't work on a 97 though.

The NB MAF is less restrictive, but I have no idea if it would work with a 97 ECU or not.

NA MAF:
https://www.miataturbo.net/attachmen...ine=1374654789
NB MAF:
https://www.miataturbo.net/attachmen...ine=1374654789

Looking on ebay, you can get a 99 MAF for $40; let's imagine that it worked right with nothing but some wiring harness hackery (possible, but unlikely) and let's say it's worth 2 hp. At $20/hp that's about the same ratio as a turbo kit. The downside is that you'll be throwing that $40 away if/when you get tired of tiny hp mods that you can't feel and go to a megasquirt. It's the same as how a header is a waste of money when you get tired of piddling little naturally aspirated mods and go with a turbo. :)

--Ian

Thank you. The best reply yet.

I was thinking something along the lines of a 4.6L MAF

https://www.miataturbo.net/attachmen...ine=1374669841

Or a Bosch MAF

https://www.miataturbo.net/attachmen...ine=1374669841

Tell us more about spending hundreds of dollars in order to make 0.25rwhp...

That's.... not really correct at all. They're using the flapper boxes you speak of, which are not present at all in any KL car.

They're using RX7 units, and the K-code Hybrid is probably something to do with F2-powered 1st gen MX6/Probe.

The KL unit is more of a "sliding booby nipple" type deal. I personally think it's far worse than a flapper, which is probably why those guys pick up so much power with a Millenia MAF conversion.