MAP conversion

[Nameless EJ6]

How would one go about converting to a MAP sensor using a PFC?

Could I use say a Honda map sensor with a missing link and run the wiring to the ECU and change the settings on the PFC to a MAP input?

Would be hard to do on the 26 because of the ITB's, but with an aftermarket manifold and single TB I'm thinking a setup like this would work, right yA'll?

I'm sitting here doing homework and it popped into my head.

[IvoryJ30t]

if its even possible. the MAF sensor is a direct measure of the amount of incoming air.

the map sensor just helps the computer guess how much air the motor is moving due to rpm, air temp, and pressure.

to be really accurate with a turbo car, you really need an exhaust MAP sensor to reference the exhaust backpressure.

you would need to retune completely, if it is possible in the first place.

[goofynick6]

Quickly translated: NO

[BoostFab]

to be really accurate with a turbo car, you really need an exhaust MAP sensor to reference the exhaust backpressure.

there's no such thing as "an exhaust map sensor"... MAP = Manifold Absolute Pressure.

Technical definition: The Manifold Absolute Pressure (MAP) sensor is used to monitor intake manifold pressure (engine load). It sends voltage signals to the Powertrain Control Module (PCM) that represent the engines varying load conditions.

about the PFC, it can process MAP sensor signal, but I'm not sure what is involve in converting MAF to MAP...

[TurboS14]

Hey Danny. You got mail regarding the adapter box. Havent heard from you last couple of days. Thanks

[Wulfgang]

there's no such thing as "an exhaust map sensor"... MAP = Manifold Absolute Pressure.

I think you missed IvoryJ30's point. To be REALLY ACCURATE on a turbo (when not using a MAF) it would be nice to have a MAP sensor on the exhaust manifold. I believe he suggested this because reversion is so much higher on a turbo engine, which is something the intake MAP really cannot see. But finding an inexpensive MAP sensor that functions at 800-1000ºC would be impossible.

[eh?]

Uh not sure if I missed something but Apexi makes a Map version of the PFC for the RB26. Djetro version.

[IvoryJ30t]

yes, exhaust manifold absolute pressure sensors exist.

used only on high end standalones.

only makes a small difference, but it still helps to be exact.

[Wulfgang]

yes, exhaust manifold absolute pressure sensors exist.

I said inexpensive. If you're willing to pay, you can even get in cylinder pressure sensors

[DSMs_Suck]

Yea honestly the MAF setup really is a better setup. Assuming you can find a low restriction maf, like IVORY stated, it is a DIRECT measurement of the incoming air, where as the MAP + IAT combo depends on A LOT of variables and will be harder to tune initially and will require retuning just about everytime you add a new go fast part.

<- Getting rid of Nissan MAF and goin to GM MAF

[Nameless EJ6]

Quickly translated: NO

And what's your input?

No? It's been done numerous times.. I've even read that it's MUCH better to have a MAP.

[eh?]

It's much better to have MAF... for the reason DSM mentioned. Also on the Skyline Boards Sydney kid gives his reason for using MAF. For a Sub 700rwhp car I'd take Maf over Map any day. But you come from the honda scene so you probably feel otherwise.

[Wulfgang]

It is not "better" to have either one. This is obviously a very subjective decision, as can be seen from all of the MAP vs. MAF debates on the web.

Like Nameless, I have also read that MAP is better. And I have read that MAF is better. Honda uses MAP. Nissan uses MAF. Find a good reason to use one or the other and run with it.

[IvoryJ30t]

honestly, i like maf systems better because they adapt to change better, and its a direct measurement of airflow instead of calculating airflow based on pressure, known VE, and temperature.

a map system is good, but changes that affect the motors VE require retuning.

if you have made all the major changes that you want to make, and tune the map system properly, it will be fine.

the maf vs map debate really gets going when your dealing with stock cars that you want to modify. in that case, a maf system will be more adaptable because the maf is measuring the increased airflow.

if your car is already modified to an extent that your happy with, and dont want a maf sensor restricting airflow, then convert to map.

if you not done modding the motor, stick with the maf until you are close to done. otherwise, that shiny new intake is gonna be a few hours on the dyno.

its a tradeoff, like everything else.

map sensor is not as fragile as a maf sensor, but the maf is more accurate due to it being a direct reading. maf easily adapts to change, but a map system needs tuning with changes to VE.

[underground]

I bought the MAP setup, but due to the being told tuning would be hell unless I converted to a single throttle body setup, I pulled off the Apexi Power FC D-Jetro...

RX7.com, buddies of mine, think I'm crazy, and would much prefer the D-Jetro...

But, I am going with the regular power FC, as I think it will be much more streetable...

But yes, if going over 700HP, MAP is the only way to go...

Dont even consider MAF for that level...

[DSMs_Suck]

I bought the MAP setup, but due to the being told tuning would be hell unless I converted to a single throttle body setup, I pulled off the Apexi Power FC D-Jetro...

RX7.com, buddies of mine, think I'm crazy, and would much prefer the D-Jetro...

But, I am going with the regular power FC, as I think it will be much more streetable...

But yes, if going over 700HP, MAP is the only way to go...

Dont even consider MAF for that level...

Electronics are electronics man. There are MAFs big enough to support 700hp, the only reason everyone runs MAP at that level is because most people are trying to squeeze every last little bit out of their setup and the MAF poses a small restriction to the intake. Again, MAF inherently measures the incoming air better than speed density system.

[Sil240]

One you can't use a honda one because my friend with a turbo integra has do get a aftermarket MAP sensor so that he can turn up the boostTwo there is the Apexi Djetro like people said beforeUnderground i know that Greg at super street is running that unit on his SR and he says its great, I dont know about the RB26 though

[Nameless EJ6]

One you can't use a honda one because my friend with a turbo integra has do get a aftermarket MAP sensor so that he can turn up the boostTwo there is the Apexi Djetro like people said beforeUnderground i know that Greg at super street is running that unit on his SR and he says its great, I dont know about the RB26 though

You don't need an afrermarket MAP sensor. It's called a missing link, you bolt it onto the MAP location and the sensor bolts on top of it. I've turbo'd 3 Hondas and this is what I used on all of them.

Anyways, you really can't use one from a Honda because it's made to fit the throttle body. You would have to fab a location for it or use one from a different car.

I'm fine with an AFM, but I've heard of alot of high HP RB people using MAP's instead... thus is why I thought about it. I'll probably never reach the point where I need to think about using one ..