do I need a FCD now?
#1
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do I need a FCD now?
here is what I have.
87 TII
Down pipe
Hiflow cat
RP exhurst
Apexi BOV
do I need to a FCD to avoid the boosting problem? Do I need a fuel pump as well?
thanks for the help.
87 TII
Down pipe
Hiflow cat
RP exhurst
Apexi BOV
do I need to a FCD to avoid the boosting problem? Do I need a fuel pump as well?
thanks for the help.
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Alcohol Fueled!
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The ECU detects a certain PSI of boost from the atmospheric sensor, I believe its somewhere around 8.6 PSI. If it hits this level, it cuts fuel to one of the rotors (the rear I believe). This prevents the motor from detonating. When you start running boost levels higher then that, you need an FCD, which "clamps" or basically tricks the ECU into seing a lower boost level then you are actually running. But your mods (especially the cat) really dont warrant one at this time. But if you plan to do any more stuff, you might want one. The Cat you have is a good way to control boost, you could add an MBC, and run up to 10 PSI. Then you would DEFINATELY need an FCD.
Jarrett
Jarrett
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#9
Alcohol Fueled!
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Well, boost sometimes changes depending on which gear you are in... I believe its dependent on how long your turbo sits in the "sweet spot". In 4th, your turbo is probably in the sweet spot long enough to generate more then 8.6 PSI of boost. So my original statement was inaccurate. You need an FCD.
Jarrett
Jarrett
#10
I'm a boost creep...
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Re: do I need a FCD now?
Originally posted by New2ndgen
do I need to a FCD to avoid the boosting problem?
do I need to a FCD to avoid the boosting problem?
The stock ECU has a fuel cut at 8.6psi boost. A FCD intercepts the pressure sensor signal and lies to the ECU about the boost level, telling it it's below 8.6psi even though it isn't, to avoid fuel cut. Use these with caution, as the further you go past the fuel cut point, the greater the error in fuel and ignition control.
Your free-flowing exhaust will probably cause boost creep, where the wastegate cannot control boost because of the additional flow. The problem is the very small size of the wastegate. The solution is to remove the turbo and port the wastegate, preferably fitting a bigger wastegate flap at the same time so the port can be even bigger.
Do I need a fuel pump as well?
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Thanks for the help! Now, who make a very good FCD? I am thinking HKS but they dont make one for FC and if go with the universial will that be a trouble to install it?
#13
Originally posted by J-Rat
Feels like your hitting Dr0x....
Feels like your hitting Dr0x....
A BOV releases positive manifold pressure prior to the throttle body. A wastegate makes the exhaust gas bypass the turbine in the turbo, limiting how fast its spinning. As for the FCD, private message guru on this board and ask him for one. He sells them for a decent price. I believe someone tested the racing beat fcd and it was clamping at like 3.2v, not 3.6v like it should.
Last edited by dr0x; 06-10-03 at 05:40 PM.
#17
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Originally posted by New2ndgen
Thanks for the help! Now, who make a very good FCD? I am thinking HKS but they dont make one for FC and if go with the universial will that be a trouble to install it?
Thanks for the help! Now, who make a very good FCD? I am thinking HKS but they dont make one for FC and if go with the universial will that be a trouble to install it?
Jarrett
*edit* never tested the clamping voltage though...Hmmm...Might have to do that.
Jarrett
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