i'm wondering which fcd will work for the 1jz? will one off of a 7m or 2jz work for the 1jz? does the 1jz need a FCD for 14-16 psi? what is the difference between boost cut and fuel cut? samething?
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what FCD will work on a 1jz?
- Thread starter 86_sports_1jz
- Start date
I'm boosting 20psi with no problem. I've always read on here to not use the FCD's because it's there for a reason. I have a brand new one and never installed it. I bought it before I read not to use it..............good luck.
1JZ fuel cuts about 14-15 psi, so yes you would need one. a 2JZ one might work, but there are 1JZ ones for sale as well.
you can use a HKS FCD , the same one as the MR2 and MKIV. Be careful when you use it because it leans out your system so make sure you have a AFC to correct it.
Apexi NEO AFC & you could use the vtec controller option for something else like to kick on water injection at certain rpms
You can get the Greddy or the HKS, both work fine.86_sports_1jz said:
You can try Ebay or local shops should carry them.
7M boost cuts based n the AFM signal, 1JZ 2JZ and MR2 all cut based off of the MAP signal (The same MAP sensor IIRC, that's why the FCDs are interchangeable)
So, no a 7M one would not work, it's a different signal.
So, no a 7M one would not work, it's a different signal.
Please just don't run a FCD.. all a FCD is keep the map signal from reaching beyond a certain point (just before fuel cut). Whats wrong with this?...a lot. That map sensor tells the injectors how much fuel to dump.
For example.. we'll say that the map sensor read's "boost" since thats the easiest way to describe it. You're running 20 PSI, the FCD only allows the ECU to see 14 PSI... therefore the ECU is only going to put in fuel for that 14 PSI of boost.
Adding fuel with an SAFC will not help (I've tried on the dyno), because what you're doing with the SAFC is telling the ECU how much fuel to dump in, by modifying that MAP signal. Even if you add 5% fuel, you won't get anything because the stupid FCD is only allowing the ECU to see "14 PSI", no more.
You can use an FCD, but you need to be smart about it. When using an FCD the easiest way to tune is with the fuel pressure (yes, you'd need a fuel pressure regulator). This way you can mechanically add fuel without going through the ECU. The ECU will automatically adjust for cruising, so rich on cruise shouldn't be a problem. A wideband O2 is required to run an FCD (for anyone who has any sense at all).
*same rules apply for 7M FCD, only instead of changing the MAP sensor signal it changes the AFM signal.
For example.. we'll say that the map sensor read's "boost" since thats the easiest way to describe it. You're running 20 PSI, the FCD only allows the ECU to see 14 PSI... therefore the ECU is only going to put in fuel for that 14 PSI of boost.
Adding fuel with an SAFC will not help (I've tried on the dyno), because what you're doing with the SAFC is telling the ECU how much fuel to dump in, by modifying that MAP signal. Even if you add 5% fuel, you won't get anything because the stupid FCD is only allowing the ECU to see "14 PSI", no more.
You can use an FCD, but you need to be smart about it. When using an FCD the easiest way to tune is with the fuel pressure (yes, you'd need a fuel pressure regulator). This way you can mechanically add fuel without going through the ECU. The ECU will automatically adjust for cruising, so rich on cruise shouldn't be a problem. A wideband O2 is required to run an FCD (for anyone who has any sense at all).
*same rules apply for 7M FCD, only instead of changing the MAP sensor signal it changes the AFM signal.
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SupraHero, how are you boosting to 20psi without FuelCut?
Ive hit FC at 12-13psi and its violent! Im trying to figure out if things are "off" or if my AEM Boost Controller is not accurate so although I set it to 13psi, its boosting slightly higher and thus allowing me to hit FC.
Ive hit FC at 12-13psi and its violent! Im trying to figure out if things are "off" or if my AEM Boost Controller is not accurate so although I set it to 13psi, its boosting slightly higher and thus allowing me to hit FC.
fcd is fine if you run it with an fcon with it's own map sensor to read over 2 bar (atmosphere PLUS 1 bar), otherwise not safe to use by itself.
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If anything you want a Greddy BCC (Boost Cut Controller) Or do it the smarter way with a 2jz map sensor and JDM 440s.
boost cut controller.
fuel cut defenser.
same. They both fool the stock ECU to allow for higher boost.
fuel cut defenser.
same. They both fool the stock ECU to allow for higher boost.