map sensors

[chopper69]

this appears to be a new question regarding this car

can I turn a gf8 Wrx (turbo) to sti eg ecu ,airflow meter,440cc injectors?

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Iv got a 75 ecu and yellow 440cc injectors and orange airflow meter but im to scared to try them does any body no if I can change my map sensor from frequency to a voltage map sensor the reason im asking is cause iv got a fuel cut defeater that only works on a voltage map sensor but I have a frequency map sensor so it wont work I have a map sensor off a 93 Subaru legacy gt single turbo that I had my fcd hocked up to \'can I put the map sensor frm my old single turbo legacy into my 98 Wrx gf8?

[kamineko]

the factory subaru MAP sensor is 5V \'voltage\' type. for your \'98 WRX it should be part number 22012-AA090

the factory ecu is expecting particular sensors, this goes for AFM, MAP, TPS etc. you can\'t just swap in any old thing.

some helpful advice, forget about the fuel cut defeater unless you know exactly what you are doing

[chopper69]

I installed boost cut defeater on my single turbo legacy and it worked hocking it up to map sensor but wont work on me 98 Wrx gf8

[Marky]

A frequency and a voltage are completely different things

Its like AC and DC power - they cant be swapped between

To be completely honest the FCD is asking for trouble with what you\'re doing already - if you\'re scared to try the other ECU you should be even more scared of using a fuel cut defender to bypass the factory boost cut

... yeah what kamineko said in other words

[chopper69]

Marky that name sounds gay so ill call you mark I like how itsays under your coment complete guess work or all lies all im trying to do is put my boost up a couple more psi then standed iv put a bigger fuel pump in and a fuel pressure regulater iv uped the pressure so my in jectors are runing 440cc now so I just want to up the boost a tiny bit without fuel cut

[Pappu1]

Bro so just to confirm u got the 7s Ecu running now or still in progress?

Cos we have done a few v3/4 Wrx to Sti setup and mostly just put in the yellow inj and orange afm and the 7s Ecu

Didn\'t change other stuff

Kept fuel pressure same as stock

Bigger fuel pump was a good idea u did

Anyway the 7s stock boost cut I think is 22 psi or so

Can remember exact number but have run 20psi and it didnt cut

That was on a vf22 and the car went really quick

Without fcd I wud say u will get at least 20 odd psi and that is a lot

If u really really Wana run fcd maybe run 2 map sensors

1 stock as let Ecu use it and get creative on addin a second to get the fcd to read it

Umm what turbo u running?

U can always put a bigger turbo and at sMe boost it should work out quicker

Also maybe stick in a wideband sensor to ensure u not leaning out etc on top end as 20+ psi and yellows = nearly maxing out region

Umm yea that wud be another reason not to fcd as u will be maxing out the yellows injectors at few more psi than cut

[Marky]

Hey uncle chopchop I\'m trying to help you here don\'t be a dick about it aye

I could just say "get an FCD which can cut a frequency" - you could use a low-pass filter of sorts if you wanted to muck around with it

As ^ he said it\'s asking for trouble, the cut is there for a reason

You could do it the old-school way as well - use a relief valve set to say 2-3psi below whatever psi yours cuts at - teed off the line to your MAP sensor (or a regulator inline on the hose instead) to make it so the MAP sensor never actually sees the boost that your car cuts at. I\'ve done it on an old city turbo and it worked perfect (well, kinda perfect) - let me run 20psi with an ECU which cut at about 15

[Roo]

Why the fuck do you need a fcd for a couple psi?

I like to push my boost but an fcd is just a terrible idea, anything up to boost cut the ecu will compensate for.

After that you\'re on your own, not just fuel wise but timing can\'t be calculated either.

Frequency and voltage are two different signals. Frequency is digital and voltage is analogue, there are IC\'s that can convert one to the other but that\'s more effort than it\'s worth.

Since you aren\'t going to listen to us, just go and buy the right fcd for your car?

[kamineko]

 Roo said:

Frequency is digital and voltage is analogue

i know you know what you mean, but that statement using those terms is over simplified and inaccurate frequency is a complete oscillation over time, the waveform can be anything, not just a \'digital\' square wave. an analogue voltage can also represent a digital state.

anyway, locking this thread down, OP is clearly more interested in making fun of users than listening to helpful advice

[chopper69]

Sorry marky I was just having a bad day ur a good guy I hope we all good every one been helpfull on club sub thanks guys for all ur help does any one have a dieagram how to full the map sensor so it thinks its geting less psi and do I need a one way valve cause doesnt the map sensor need to read vacuum to?