Hello, i've just recently purchased a 93 vr rx-7 with about 30,00miles on the rebuild. while just looking thru the powerfc i notice that my injector duty was at 100percent on the primarys and secondarys if i wasnt mistaken.
I rember reading that the injector duty should not be higher than 85%. This car is untuned, running a pfc version 5 sumthin, with pfs catback,downpipe,high flow cat, and apex intake, should i lower the injector duty? i'am scared to because i dunt want to run lean, and pop the motor, advice please..... thanx in advance

 

also i forgot to add im running the stock 550 and 850 injectors

 

I'm guessing you are running more than 10lbs boost then? Get larger injectors and have the car tuned

 

you shouldent be maxing out the injectors with your setup, what boost are you running...

I reccomend you take it to a rx7 tuner.

 

On some systems 100% = Stock and 150% = Stock and then 50% more... so if you're running 50% Max Duty Cycle... = 100% then 150% = 75% Max Duty Cycle...
Make sure you know what you're looking at...

 

does it read 100% on the commander when you are driving it or just when you are scrolling the commander with the car off?

 

if it's just 100% when you're going through the injector menu, it is perfectly normal. that's how you want it, unless you need to richen it up some or lean it down. the 100% indicates that it's using the exact amount of fuel that it's told to in the fuel map. 110% would be an extra 10% at whatever rpm range you set it for.

when you go to monitor, just select 1 item and make it your injector duty. that will tell you how much of your injector u are actually using

 

100% on the peak hold means you are maxing out the injectors, the engine could be needing more fuel than even that but you would not know it. All you need is one cold morning and pop. I have approx the same mods and was having the same issue. My options were to upgrade the injector size or turn down the boost a little. I chose to turn down the boost for a while until I get the cash to upgrade. My guess is you are running 12-13psi. I turned it down to 11psi and I am fine for now, maybe hit 85% now. 100% in the setup menu is someting else and you should leave it alone.

 

I think he is in the injector setup screen that sets the injector size and duty it can not go pass. He is not in the monitor screen. Right Showoff? You saying you're getting 100% on primaries and secondaries leads me to believe so. You can't read max on secondary and primary injectors, just injectors as a whole.

If you are in fact in the setup screen, than that is normal. 100% is where it is suppose to be

 

Yea i'am not maxing out on the commander i'am just talking about when i'am scrolling thru the injector settings with the car off i saw the injector duty setting at 100percent and i got a little worried, but thanx for letting me know its normal, i'am only running 10pounds of boost until i get the car tuned. also, what is the fuel system's max capabilites, 1 bar?

 

i dont know how much of the gospil this is, but it seems pretty close

http://rx7.com/cgi-local/3rdgencalc.cgi

 

showoff:

Don't be offended, but you really need to learn what you are doing before you start messing with things in the PFC. One small change in the wrong place can blow your motor.

I wouldn't change any of the settings until you spend a bit of time researching -- and start by reading the PFC manual.

 

ryanberg: I'am totally not offended, cuz i haven't changed anything on the pfc, if you read my first post i wanted 2 make sure the 100percent on the injector setting page was alright, because i was to scared to make any changes because i understand that the pfc is a full standalone unit, and 1 wrong change can pop your motor, but i got this car secondhand with the pfc already on it untuned so i just wanted to make sure the previous owner hasn't set a setting wrong. but thanx 4 your concern, unlike most newbs, i did every lil bit of research possible before i bought the car, but theres a couple things here n there tht i missed, 1 being that 100percent on the injector setting is normal

 

Showoff, I would go into the PFC and reset it to the default settings. That way, you know where you stand.

If you reset it, you may have to relearn the idle:

a)start car and let run for 10 minutes with no accessories (fans, lights, etc).
b) turn on rear defroster and let idle 10 minutes
c) turn on a/c and let idle for 10 minutes.

I would do this at night with the hood up to minimize temps.

 

thanx for the advice ill do that tonight, on the brightside i maybe be getting it tuned professionally this weekend, but thanx for the advice

 

rynberg, does the pfc come with a base map programmed in it? i have one sitting in my apartment and i'd love to put it on just to see what kinds of readings i have at the moment. i plan on getting it tuned soon when i add my intake kit. right now, i have dp and cat-back and that's it so i'm good with the stock map settings (i think). could i install the pfc and not be paranoid that its going to kill my engine? or should i wait and have a pro do it?

 

You're perfectly fine with the base map with a downpipe and catback. Just run 10-11 psi to be safe until you get it tuned.

I would read the manual a few times and do some research so you are familiar with how it works and how to make changes before you install it.