Forced Induction 331 W/ V2 Si Set Up Questions

Discussion in '1994 - 1995 Specific Tech' started by 331SNAKE, May 9, 2012.

  1. Hi there,

    I bought an unfinished 1994 GT project and would like to try to set this car up right so it will run good and achieve some nice hp numbers. Currently the car runs fine. I had to have the vortech v2 s sent out for new bearings and had them instal an upgraded si impeller. I have asked this question to a few shops and have got different answers. Some have told me to change the fuel pump, others have told me the fuel pumps are fine and to change the injectors to 60lb and change the mass air to 90mm. Any suggestions are welcome. This car is primarily for the street with occasional strip usage.

    Here is the current set up:

    DSS 331 stroker
    anderson motorsport cam
    Trick Flow twisted wedge heads with 190cc
    trick flow street heat intake
    vortech fmu (which i think can be deleted)
    42LB injectors
    aeromotive fuel pressure regulator
    bbk 75 mm throttle body
    air prom 76mm mass air
    egr delete
    vortech v2 si with 3" pulley 8 rib pulley set up
    anderson power pipe
    bbk shorty headers
    bbk off road h pipe
    2 wide band 02 sensors
    flow master 3 chamer exhaust
    wallbro 255 lph in tank pump
    t rex in line pump

    What would you recommend changing in this set up? Thanks for the input.
  2. Everything you have should support up to around 500 HP easily. Just make sure the pump is actually a 255 and nothing less, or it will be a disaster! Your tuner will be able to tell if you run out of fuel on the dyno. Those 42's will probably be nearing their max at 500 hp so if you plan to make anymore than that, you might want to consider the 60lb injectors along with an inline T rex type fuel pump or a kenne bell Boost-A-Pump.
  3. It looks like you have a nice setup that is going to make a lot of power the way it is. You are going to need to make sure that you have at least one step colder copper spark plugs gapped to 0.028 and you are probably going to want to install an MSD 6al or a Boost-a-Spark to ensure there are no misfires at high boost - a problem that my car was having at 10 psi.
  4. nice setup so far. i would say if you're doing to upgrade to 60s right away. wish i would have done that in the first place. ditch that FMU. what AFM cam? what are you tuning with?
  5. Looks like you are getting good advice from my standpoint. It will work ok with the FMU, but if you really want to get the most of it, a bigger MAF and 60lb injectors will work better than the current setup with an FMU.

    The 255lph with the T-rex should be sufficient. I was almost able to get away without the T-rex on my setup, and just the 255lph in tank. When I went from a 125 shot to a 150 I had to put the T-rex in to keep the pressure from bleeding off. I'm injecting at almost 100psi of fuel rail pressure as well, so your fuel demands are actually quite a bit lower than mine due to the lower injection pressure.

  6. Opinions being what they are, here's what I would do:

    Ditch the FMU. You don't need it with 42's and if you're having difficulty supporting your current mods with 42s then I'd suggest that something else is amiss. The FMU (if it's operational) is working against your fuel supply system with your current setup (although the T-Rex off-sets a lot of that).

    Remove the T-Rex and install a Boost a Pump. The T-Rex is a great thing to have for setups that requires higher pressures (i.e. FMU setup) but the trade-off is fuel volume. The BAP at minimum, will regulate voltage and current to the in-tank pump and keep it constant. It's also adjustable if you find you're not getting the volume of fuel you need. A high pressure in-tank pump would be ideal but it's not 100% necessary if you have the BAP. One other note about the BAP... it comes with a boost pressure switch. Toss that switch in the trash and run the pump at a consistent power level.

    Consider getting a Boost-s-Spark as well. You didn't indicate what setup you have for ignition but IMO, the OEM ignition system is perfect for a boosted app. It makes a very long duration, fat spark. Increase the intensity with a BAS and once again, ensure that voltage to the coil is constant and the saturated. You can adjust up and down until you hit the sweet spot and everything works as advertised.

    As for larger injectors well.... You will likely run out of fuel rail (if using OEM) before you run out of injector with those 42s.