Initial map for injector change?

GeorgeRex · 11-12-2005, 02:52 PM

Hi all,

I recently changed my injectors to 720cc Nismos. I took a realtime map and changed the injector scale to 3360 from 5372. I based the reduction on a ratio between the stock injectors (450cc) and the Nismos (720cc).

I then loaded the real time map using the AccessPort. When I started the car it seemed to be running very rich and did not want to rev cleanly. How can I tell that the real time map is in effect? Any thoughts on playing with the scale? I will be getting properly tuned in a month or so. I just need to get by for now.

keyser_soze · 11-12-2005, 03:11 PM

George...I made a similar mistake...actually for larger injector you have to put a smaller scale value...you want to take (original size/new size)*scale value ...its in the help file

good luck...

GeorgeRex · 11-12-2005, 03:27 PM

Keyser,

I did use a smaller value - I used 3360.

keyser_soze · 11-12-2005, 03:29 PM

ah ok...Did you update the injector deadtime table?

GeorgeRex · 11-12-2005, 04:27 PM

Quote:

Originally Posted by keyser_soze

ah ok...Did you update the injector deadtime table?

No, I thought only PE injectors required that ?

04stiguy · 11-12-2005, 11:20 PM

Try 3990 for a good baseline for those injectors. This assumes stock MAF and airbox. You must monitor your long and short term fuel trims to determine what you need to adjust your scalar to.

GeorgeRex · 11-13-2005, 02:02 PM

Quote:

Originally Posted by 04stiguy

Try 3990 for a good baseline for those injectors. This assumes stock MAF and airbox. You must monitor your long and short term fuel trims to determine what you need to adjust your scalar to. Dont adjust latency.

Thanks for the tip. I ended up using 3550 but then all tuning had to stop because of a major problem which I will share at the right moment ( need to resolve with vendor first).

***MidlifeCrisis*** · 11-13-2005, 08:27 PM

You'll want to start around 3880. What year is your car? Various discussions have the stock injectors anywhere from 480 to 550. My 04 stock injectors actually were tested and flowed at 520 (all 4 were the same). I have PE850s and the injector scale factor appears to be about right at 3476.

GeorgeRex · 11-14-2005, 10:00 AM

Thanks all,

I am dead in the water right now with the ECU in limp home mode so I cannot tune any further. I will provide details later.

11-12-2005, 02:52 PM	#1
GeorgeRex Junior STI Driver Posts: 186 IWSTI Addict since: Feb 2004 Trader Rating: (0)	Initial map for injector change? Hi all, I recently changed my injectors to 720cc Nismos. I took a realtime map and changed the injector scale to 3360 from 5372. I based the reduction on a ratio between the stock injectors (450cc) and the Nismos (720cc). I then loaded the real time map using the AccessPort. When I started the car it seemed to be running very rich and did not want to rev cleanly. How can I tell that the real time map is in effect? Any thoughts on playing with the scale? I will be getting properly tuned in a month or so. I just need to get by for now. This ad is not endorsed by this member. Please register or login to hide this ad.

11-12-2005, 11:20 PM	#6
04stiguy Senior STI Driver Car: '05 STi Fav Mod: Cusco Zero 2R's Posts: 335 IWSTI Addict since: Jun 2004 Trader Rating: (0)	Try 3990 for a good baseline for those injectors. This assumes stock MAF and airbox. You must monitor your long and short term fuel trims to determine what you need to adjust your scalar to. Last edited by 04stiguy; 02-11-2006 at 10:18 PM.

11-14-2005, 10:00 AM	#9
GeorgeRex Junior STI Driver Posts: 186 IWSTI Addict since: Feb 2004 Trader Rating: (0)	Thanks all, I am dead in the water right now with the ECU in limp home mode so I cannot tune any further. I will provide details later. This ad is not endorsed by this member. Please register or login to hide this ad.

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11-12-2005, 03:11 PM	#2
keyser_soze Professional STI Racer Car: WRB, 2005 STi Posts: 673 IWSTI Addict since: May 2004 Trader Rating: (0)	George...I made a similar mistake...actually for larger injector you have to put a smaller scale value...you want to take (original size/new size)*scale value ...its in the help file good luck...

11-12-2005, 03:27 PM	#3
GeorgeRex Junior STI Driver Posts: 186 IWSTI Addict since: Feb 2004 Trader Rating: (0)	Keyser, I did use a smaller value - I used 3360.

11-12-2005, 03:29 PM	#4
keyser_soze Professional STI Racer Car: WRB, 2005 STi Posts: 673 IWSTI Addict since: May 2004 Trader Rating: (0)	ah ok...Did you update the injector deadtime table?

11-13-2005, 08:27 PM	#8
*MidlifeCrisis* Platinum Member Car: WRB 04 WRX STi+++ Fav Mod: Tech Exec Location: Golden, Colorado Posts: 153 IWSTI Addict since: Jul 2004 Trader Rating: (0)	You'll want to start around 3880. What year is your car? Various discussions have the stock injectors anywhere from 480 to 550. My 04 stock injectors actually were tested and flowed at 520 (all 4 were the same). I have PE850s and the injector scale factor appears to be about right at 3476.