Xcessive

Are ther any electronic wizzes out there that might
be willing to install larger injector drivers on a PFC
circuit board. Need to install new higher current capability fets for low impedence injectors. Give me a call if anybody interested. My electronic skills from college are way to rusty to attempt, or better said im to old and shaky now. Thx Ralph 503-256-3278

Xcessive

I found and engineer friend of mine to make my changes. Thx anyway Ralph

rotarypower101

iTrader: (1)

Hey Ralph, when you get the pfc to work with 4x1600 can you do a little write up about it?

DaleClark

iTrader: (55)

You just need to add resistors to run low impedance injectors - it's not rocket science. Mazda had the exact same setup in the early 2nd gens.

Do a search on injector and resistance, problably check the single turbo forum too. I've done it many times - heck, you can do it with $2 in parts from Radio Shack.

Dale

RX794

The reason Ralph doesn't wanna use resistors is because it will slow the injectors down.

Wargasm

I do believe you that the resistors slow down the injector opening time... but do you have any "hard data" showing how much this effect is?

Brian

Xcessive

Brian , I have found that the 1600s with resistors, under higher boost 26psi+ and 70+ duty cycle makes the car surge under long lruns, this is with 43psi base fuel pressure constant. The best way I found to test this was I boot strapped the resistors with ong wires hanging out of manifold, then ran the care some good pulls then cyt the wire putting the resistore back in use
and did some more pulles. It was amazing the difference
between the two. Think about it this way,manufacturer
specs= low impedence= 4+amp switch and 1 amp hold
(peak&hold) High imp.= 1 amp switch (saturated)
this means to me that the low impedence requires 4X
the current to make injector work to specifications.
sorry for the length, I have tried to get RC and others to measure the diff, but they just act like they dont care.

93 R1

Sounds like evidence to me

RX794

Tell me about it, I've been trying to get RC to measure the lag time of my injectors, and they can NEVER give me a certain straight answer, but whatever. Ralph I do have a question for you though, I know me and you once spoke on the phone about the RC bored out 850 to 1200cc injectors in the primary position once, Did you ever get around to trying this? Can you tell me the results if so? Thanks.

Fish

Ralph any chance you could send me details of the location of the fets that need changing, and their location on the PCB.

Thanks
Dan

twokrx7

iTrader: (1)

X

Sorta offtopic but I gotta ask ... are you running a constant 43 psi fuel pressure with no compensation for boost?

Xcessive

Rx794 RC tried to convince me there was no diff in lag from low to high impedence with one amp current. Whatever! Dan, Its a 4 driver package, Ill get the pinout
off the plug in and send that and a description of location. Ill also get the Ic # off the chip.
twokrx7 Its a RR regulator Magnaflow Big boy.
Ralph

Fish

Ralph, any updates on this.

Thanks
Dan