View Full Version : Power FC/Datalogit users, please help!
DJ_Sunrise
05-19-2007, 01:08 PM
hey guys.. i have an s14 with s14 SR running.. you guessed it.. power fc... i bought 740cc injectors for the mofo, and i was wondering if theres a way for me to input the larger injector size into pfc?
im going up to dentsport garage for my tuning, and i would rather swap the injectors myself and drive up there.. instead of paying them $150 for the install.
i have datalogit, but for whatever reason i could never get any laptops to recognize it.. i probably have a cable here or there in the wrong place. maybe someone can tell me which spot the two wires are supposed to be in, on that white box???
-Bart
d r i f t swift
05-19-2007, 02:38 PM
not my info.. but i got it from here..
http://www.members.aol.com/srfiveten/pages/PFC.htm ..
"When upgrading injectors or increasing fuel pressure, each cylinder can have its injector duty and lag time adjusted via FC Commander.
If you were to upgrade your stock 370cc injectors with a set of 740cc injectors, a quick calculation is required to setup the Power FC.
[old injector cc] divided by [new injector cc] multiplied by 100 = % to be entered.
(370 / 740) x100=50.0%
So, for injector #1~#4, use the arrow keys to enter 50.0%
To the right of % column, there is a column for Injector Lag Correction.
When the ECU commands an injector to squirt, there is a split second lag for the gas to actually make its way out through the tip.
Larger injectors seem to have longer lag.
Some injector manufacturers advertise the lag time, some donft.
Lag is measured with controlled voltage and controlled fuel pressure.
According to Apex-I, stock 370cc injectors of S13 and S14 SR20DET measured 370cc/min with 0.580msec lag, measured at 14.0v with stock fuel pressure.
For Injector Lag Correction, you need to know or guess the lag value of your new injectors.
For example, if the lag for 740cc injectors is 0.830msec, then
[new injector lag] – [old injector lag] = correction value.
0.830 – 0.580 = 0.250msec
So, for injector #1~#4, use the arrow keys to enter +0.25msec
Injector Lag Correction is very similar to adjusting the valve timing via adjustable timing chain sprocket.
No book will show you your sweet spot. You need to experiment to find the most suitable setting for your motor and you.
"
rps13drift
05-19-2007, 04:09 PM
^^^word! Also if youre having problems with your computer recognizing the datalogit look through youre datalogit manual. I had the same problem at first then i went through the manual and followed the steps and it worked fine! and before you can make any adjustments to a map you must select read all. load up or make a new map then select write all and every thing should work!
good luck
-mike-
KawBoy
05-19-2007, 04:29 PM
Good info!
Subscribed
BTW, where is Dentsport garage?
johngriff
05-19-2007, 04:46 PM
Make sure you have your new lagtimes on those 740's ready, otherwise it will run like poop.
Also, when you do the inj correction in the PFC for as large a jump as 370-740, you'll find that everything ends up way lean.... so i'd be careful about boosting etc.
I would add 10-15% on the INJ correction, JUST TO BE SAFE. If you have a wide band then you'll be cherry.
ho1ywars
05-19-2007, 05:37 PM
yo bart, this is shawn. the kid with the s14 that works up at pepboys. when you get your datalogit working let me know. i picked up a power FC a few weeks ago and am thinking about picking up the datalogit. i would like to see how user friendly it is and all the extra stuff you can do with it though before i buy it. hit me up when you get it working. if you have trouble adjusting for the bigger injectors let me know, i know how to do it.
shawn
577-8620
DJ_Sunrise
05-21-2007, 03:50 PM
dentsport garage is located in norwood, massa. thanks for the help swift, and john. yea.. its a big jump considering the power ill be running.. total overkill.. but i dont feel like buying injectors twice, sooo i figured i would go the extra step. ive been running an xtra 10% on my stock 370s.. im sick of doing it every time i start my car haha. i dont have wide band as of yet, but ill just drive the car some what safe. thanks everyone!!! you just saved me $150 =)
yo shawn how have you been bro?? ill call you up whenever i get the datalogit working. to be honest, i like a stock oem clean look.. if you want to buy the datalogit from me, ill sell it to you. as far as the ease of use.. all things considered, as long as you know what you are looking at its not too bad to use.
btw.. i wish i had an s13 sr.. changing these injectors is going to be way more of a PITA.
-Bart
MavericStephenc
05-21-2007, 04:12 PM
running 740's is alil over but cant you adjust the duty cycle so they run like say 550's?
KawBoy
05-21-2007, 04:12 PM
Why are you going from NJ to MA for tuning?
Theres places in NJ/NY/PA that tune
MavericStephenc
05-21-2007, 04:12 PM
running 740's is alil over but cant you adjust the duty cycle so they run like say 550's?
DJ_Sunrise
05-21-2007, 04:28 PM
the reason im driving 5 hrs to get my car tuned is the same reason why i would bring my ferrari to a ferrari dealership, not a lambo dealership to get worked on. no i dont have a ferrari or lambo, just stating an example. dent sport is certified by apexi for power fc, so they will free up more power and do it safer... these 740s will be absolutely fine. the point of swifts post is so the 740s.. will feel just like 370s... also, dentsport only charges $500. ma-motorsports charges how much? over 1k for a comparable tune on the same dyno.. evans which is only 2 hrs away.. deals mostly with honda/acura. im bringing my shit to a place that deals with nissans...
-Bart
MavericStephenc
05-21-2007, 04:48 PM
+1 for dsg msglgnth
Wes_s13
10-09-2007, 08:45 AM
running 740's is alil over but cant you adjust the duty cycle so they run like say 550's?
i would also like to know the answer to this question..im doing the same thing..running 740cc on a t28..until i upgrade to a bigger turbo which i plan on sometime soon.
steve shadows
10-09-2007, 11:30 AM
You might not be able to get it to recognize it because your com ports are not configured correctly on the computer.
Find out which comport is free on your computer, than configure the software to use that com port for interface.
johngriff
10-09-2007, 11:41 AM
Yes you can lean it out.
Hopefully.
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