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runs fine. the calcs ive made are right though don't know how he got +0.12

After a fair bit of searching, I was given these specs:

post-19642-1177974289.jpg

Basically I went with conservative figures, and at stock rail pressure according to these specs, the lag time adjustment should be +0.13. Similar to Birnie, when I input the numbers into the PFC my car started, idled and ran just fine. I've never felt the need to revise the settings.

Edited by Dale FZ1
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..just not sure if that column is actually Injector Latency figures though.

Look in Pauls FAQ http://paulr33.skylinesaustralia.com/docs/...erfc-faq.htm#57

either way, I've tried both settings and haven't noticed a difference.

I added another thread asking about Injector latency but haven't had any useful feedback yet

I can't say for sure, but it seems that people use the terms "latency" and "lag time" interchangably. I believe they mean the same thing. I don't know what it actually means/measures, but all I need to know is that it's a characteristic of the injector, and the ECU needs to be told what it is.

Look at Paul's link to a side feed injector spreadsheet, which I suspect he accessed same as me through the (members only) Datalogit community. I didn't have a look for, nor see any acknowledgement of his source.

The figures on that spreadsheet are at odds with what is on his main page. I went with the spreadsheet figures in the absence of other data, and it ran/runs faultlessly. :thanks:

Maybe it's not a critical value if you've noticed no difference Birnie?

Edited by Dale FZ1
After a fair bit of searching, I was given these specs:

Reduced 84%

Attached Image

906 x 181 (33.27k)

Basically I went with conservative figures, and at stock rail pressure according to these specs, the lag time adjustment should be +0.13. Similar to Birnie, when I input the numbers into the PFC my car started, idled and ran just fine. I've never felt the need to revise the settings.

Birnie Posted Yesterday, 08:39 AM

I did my injectors to 448cc and the latency as .584 - .528....... from memory

If i'm wrong and the injectors are 480cc then by having the 82.5% setting i will be pumping in too much fuel as this setting only changes a variable in the ECUs already made up for 370cc equation.

i guess as long as the AFR's are ok then regardless of the inputs its going to be safe.

So i guess i'll find out when it gets tuned.

you used the settings for the S14 injectors under them are the settings for an RB25DET so it would probably different again

Cheers for that mate.

Matt

Read the last 2 pages.... they are NOT 480cc, that's just their advertised genral rating as it's different depending on the fuel pressure.

Standard pressure is 450cc right up to 525cc with increased pressure, check the link i posted futher back or DaleFZ1's at the top of this page.

Why they picked '480' is beyond me but even the 740cc APEXi injectors are 675 at standard pressure... go figure ???

82.5 is calulated on 370/450 = 82.22222

..and as you're only allowed 0.5 increments, i rounded up to 82.5 , not down, to be safe.

If it wasn't right, i wouldn't still be getting 500kms per tank...which i am with practically no knock and a cra the feals and sounds the same as when the standard 370's were in.

A QUICK WARNING TO OTHERS :

If you calculate on 480cc, ie 370/480 = 77.08333 and punch in 77.1% you will be in a really dangerous area !

You WILL be leaning out, by a good 5 or 6 %

450cc is right I'm sure going off the SR20 spec sheet we found.

The FAQ says 448? i believe but it's the same if you calculate of the 370/450 and round up anyway.

So 370/450 = 82.2222 % rounded up to 82.5 % as only 0.5 increments allowed. You'd be silly to round down on fuel percentages

Latency i've got set at -0.06 using your FAQ figures.

I believe those figures of,

RB25 370cc/min 0.528msec

SR20 (Jap Spec Manual) 448cc/min 0.584msec (actually Aus aswell as Jap Spec, just needs to be manual)

were taken from the Power FC manual? Is that right Paul?

If so, i'm not one to argue with APEXi

0.528 - 0.584 = -0.056 (rounded down to -0.06)

Anyway, runs like a dream so I'd be confident you can post these figures. (i've had approx 700kms of highway commuting and Syd driving over the past week with no issues, getting tuned up tomorrow)

Percentage : 82.5%

Latency : -0.06

And I've run a faultless 15000km with my settings. As per previous, it may be that the lag time is not a critical value. Starts, idles and runs cold or hot without any noticeable difference from stock.

I've been waiting for a comment from those who know more than I do, and waiting, and waiting...

The lag/latency values do not seem to have made a difference to the running of either of our vehicles, and sadly there is no (none that I could find) values available from Nissan for the OE injectors. That is why I took notice of that spreadsheet.

The correction figure seems to have been the most important, and my wideband logging showed it was on the money.

Any further ideas to add Paul?

Edited by Dale FZ1

No, so I used the values that were available in that spreadsheet. I believed them credible because of the extent of data available for a wide range of injectors.

As per previous, while I don't understand what the value represents, I know that we have to input a value to correct.

  • 1 month later...

My mechanic friend advised me when I needed some for my falcon to just get them from anywhere. They're all the same stuff pretty much. I bought some from repco/auto one. Still fine after 3+ years. Not expensive either, compared to nissan direct.

there's not much to an o ring

  • 1 month later...
Just to bring up some more info i found out from 'Dale FZ1' cause he is the 1st guy I've found that ACTUALLY HAS 'EM INSTALLED !

Facts :

1) They are 450cc (as Dale used the correction value based on 370/450 to get normal results from the PowerFC)

2) JapSpec doesn't matter, as long as it was manual, Aus is OK. To be sure just check the colour.

(Just to be sure, Auto S15's have the purple ones, equivelant to the standard R33's so forget them)

Anymore info I'll be sure to add as i found out..

Catchya guys :D

Shit i never seen this thread... i have boxes of the bastards :D and use them in sr's all the time as emanages love them.

they are 444cc with a lag time of 0.5

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