Jump to content
SAU Community

Recommended Posts

ive tuned my car but this is one thing i cant seem to find an understandable answer too,

injector lag time vs battery voltage, ive noticed with my lights(or electrical drain) on im getting a richer AFR, i know why this is happening but i cant find out how to set the inj vs batt settings for my setup.

im using datalogit with LC1 and XD16 etc.

RB26 running tomei 600cc injectors 18 psi making 293kw N1 turbo's stock motor on 98

any help with settings for inj lag (ms) vs batV

current settings

16v 0.604

14v 0.772

12v 0.944

10v 1.132

8v 1.316

6v 1.396

inj settings 73.0 lag time 0.03

any help much appreciated

cheers

Jez

Link to comment
https://www.sau.com.au/forums/topic/345957-power-fc-tuning-question/
Share on other sites

if battery voltage is the only variable causing it to run richer you can adjust the settings to suit.

your 12v figure is slighty different to the base map for rb26 but the rest are the same, they're for standard injectors tho, no aftermarket injectors are going to have exactly the same numbers as factory.

at what voltage does it run normal and what voltage make it go rich? and how rich?

Normally 13.2v and with highbeam on 13v

changes from 13.8Afr idle to 13.4afr or so and richer with more load.

I tried playing with the 12v setting and ur correct the rest are stock rb26 figures.

  DVS32R said:
ive tuned my car but this is one thing i cant seem to find an understandable answer too,

injector lag time vs battery voltage, ive noticed with my lights(or electrical drain) on im getting a richer AFR, i know why this is happening

Sorry for the hijack, but can you explain why its happening? I thought it was like this; lower voltage -> higher latency -> less petrol through the injector for a given input -> leaner.

your on the right track,

there is a an adjustment for the injector lag time in milliseconds vs battery voltage, so at a higher voltage the injector will open and close faster and needs a lower lag time = less time open

at lower voltage it will open and close slower so it needs more open time,

i just need to know the correct way to set this up so at all different Voltage there is no affect on AFR's , mainly between 12v and 14v

unless you can get exact firgures from an injector test or similar the only way to set it up is with experimenting. altho .2v drop is bugger and 13v is smack bang in the middle of the 12v and 14v settings, so you might find youself having to adjust both of them to get it right.

if you want to rule out any chance of problems later you could adjust it all then pull off the alternator belt and check the afr's with a lower voltage and adjust to make sure you never get a lean out if your voltage drops lower than normal for whatever reason

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Thanks for the linkie. Certainly always a great deal of help when people post comparisons like these, but I think for now I'll stay away from any semi slicks. I did go ahead and order the sportcontact 7. My buddy has them on his modified A4 and he keeps saying how good they are. For my intended purposes these will probably work real well. I'll report on them once I had the chance to try them out
    • Talk about noisy. Even when I still had the Tomei under the car I could distinctly hear the tires rolling. And I doubt I ever will need maximum grip like on a track. My GTR will maybe never even see the 600hp mark and I need to get used to the car quite a bit before challenging the limits of its handling. For the next winter storage I think I will get a set of these rubber drive-on thingies that have a tire shaped base. Those supposedly really help prevent flat spots.
    • Well our climate is definitely way less hot overall and the weather can be quite picky at times. I just know that during normal road use or even spirited drives there is no way I'd be able to consistently stay in the operating temperature, and constantly changing the tire pressure would also be a royal pain.
    • Input shaft bearing. They all do it. There is always rollover noise in Nissan boxes - particularly the big box. Don't worry about it unless it gets really growly.
    • For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
×
×
  • Create New...