gday, ive got a full 3 inch and k&n filter on my car, the boost goes up to around 10psi then the car cuts out. basicly im trying to work out what my options are. ive searched around but still cant make my mind up what to do, im happy with the way the car performs right now apart from the cutting, id like to know what the seasyest fix is that isnt going to cause me problems. i could port the waste gate but then id end up with the same problem angain because id turn the boost up to make it go better, what i want to no is should i hold out and by a aftermarket computor or is there a easy way i can safely stop the cut and not risk damage from runing to lean? thank you for any help you can offer

 

Fuel cut is at 8.6psi boost. If you want more than that you need a fuel cut defender (FCD), and electronic circuit that intercepts the MAP sensor signal and holds it just below the cut point. Most rotary shops sell them, or they're on TradeMe for ~NZ$75. If you're good with electronics you can build your own for ~NZ$10.

If you want to keep boost below the cut point then you'll have to port the wastegate. In fact you should do that anyway because with a 3" exhaust, intake and FCD boost will creep to dangerous levels. Without fuel mods you need to keep it under 10psi. An FD fuel pump is a wise upgrade for 10-12psi boost.

 

okay, so if i install a fcd right now then it will run really lean? can anyone explain to me does a fcd trick the computor into thinking its on lower boost therefore less fuel? also i was thinking about a easy solution at work today. has anyone seen the pressure releif valves on standard intake of some turbo cars (mainly diesil)? could i fit one of those into the intercooler pipeing so every time i got to say 8 psi it would just dump the excess pressure? any opinions would be great, cheers

 

i dont think this went through?

 

FCD doesn't cause the fuel to go lean.
A "bleed" or restrictor valve will almost do the same thing as an FCd but mechanically.

http://fc3spro.com/TECH/FAQ/fuelcut.html

Please do a proper search on "FCD" - it would've answered all your questions quicker.


-Ted

 

The MAP sensor doesn't control fuelling; the main input for that is the airflow meter. The MAP sensor does however have some control of how much the ignition is retarded as boost increases, so with an FCD the ECU won't be retarding the ignition once you get over 8.6psi. Apparently the FC has quite conservative igntion curves, so this is okay as long as you don't go crazy with boost. You should also be taking steps to lower the intake temps, as this increases resistance to detonation. A cold air intake is a first easy step, and a front-mounted intercooler should be seriously considered.

 

im just used to not having air flow meters. dam hondas lol