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smartbomb
12-22-2007, 11:21 PM
I installed some RC1000 CC injectors today and rescaled them using the following scaling and invalid time numbers.

Scaling=850

Voltage----ms
4.69---------3.312
7.03---------2.023
9.38---------1.079
11.72-------0.641
14.06-------0.367
16.41-------0.181
18.68-------0.049

The driveabilty was fine but the idle was pretty rough and not stable, the engine was almost stalling. I know these injectors are pretty big to expect a stock like idle but I increased the idle advance to 12 degrees and rasied the target idle to 650 rpm and zero'ed out the intake cam advance at idle from my agressive mivec map.

Now the idle is very stable but still rough, like I have a mild cam or something. I still have to tweak the scaling after observing the fuel trims.

I would not expect injectors this big to idle well but do you guys get the idle to near stock? If so any tricks other than what I did? On Nissans you can't and thats where my experiance is.

smartbomb
12-23-2007, 12:24 AM
I'll let you know as soon as I have time to get my closed loop trims and idle trims. Just barely had time to get this going between rounds of holiday/family stuff.

smartbomb
12-23-2007, 09:03 PM
Apparently the invalid times posted on evom are way off what works. I got the idle a lot better and the LTFT's are more reasonable now. I will post what I used as soon as I play with it a little more. I am starting to get a feel for this EVO stuff.

nj1266
12-24-2007, 12:53 AM
The RC 1000 dead time numbers come from the AEM wizard. I think they are way off. The invalid times are lower than those for the PTE 680s. That did not make sense to me. Thanks for confirming that they were wrong.

alan678
12-24-2007, 01:05 AM
Try these...

Scaling=860

Voltage----ms
4.69---------3.312
7.03---------2.184
9.38---------1.560
11.72-------1.080
14.06-------0.744
16.41-------0.480
18.68-------0.312

alan678
12-24-2007, 03:43 AM
The RC 1000 dead time numbers come from the AEM wizard. I think they are way off. The invalid times are lower than those for the PTE 680s. That did not make sense to me. Thanks for confirming that they were wrong.


This is very very true....that scaling sheet is worthless to a certain extent.....i use it more to get the gap in the latency values for the injectors being used then anything else...

This is the method I use to dial in injectors, might not be the most technical or sophisticated of methods but it has worked for me so far (and is better then leaving the stock values and letting the fuel trims set from there and lean them out from like some tuners do since they don't want to waste their time dialing injectors in via the cc scaling/latency values :uglystupid2:

1) Clear the Fuel Trims from the ECU by removing the battery ground & draining the system of any charge by applying the brakes a few times or letting the car sit for about 15mins, your preference....the brake method has yet to fail me. (This is done so that the fuel trims are all at zero and that the injectors have no ECU interaction during the next start up with the new injector values). Confirm that the fuel trims are at zero by using a logger.
2) Get the cc rating of the injectors and subtract ~15% and input that as the baseline cc scale value.
3) Input the latency numbers off the AEM latency sheet.
4) Flash the new settings then turn the car on WITH the wideband software already logging.
5) After about 15-30 seconds (If the car even idles) (If the car has a hard time idling the AFR is most likely to lean...18+ AFR) you should be able to get an average AFR after the start up (at this point the front o2 sensor would not be ready and not be able to adjust the STFT thus showing you the raw AFR with the new injector values)
6) Ideally the car should idle around a 14.7. Add/subtract to the latency values to get the idle to get as close to '14.7' as possible
(Note: If the idle AFR is close to 14.7 (More then 15 or lower than 14.3) +(to increase AFR)/-(to decrease AFR) .02-.04 to ALL the latency values accordingly. If the idle AFR is far off (More then 17 or lower than 13)14.7 +/- .1 to ALL the latency values accordingly.)
7) Flash your car with the new settings and go back to step 5 until the Idle AFR is hovering around 14.7 +/- .2 with a STFT of +/-3 at idle/cruise.

Note: I use Mitsulogger to dial in injectors due to the ease of reading the Fuel Trims.

Use the below to 'Fine Tune' the injectors after obtaining a good baseline, if needed.....dont spend to much time on this or you will find yourself chasing your own tail...



Originally Posted by l2r99gst from Evolutionm.net

On average, your crusing injector pulsewidths will be double your idle injector pulsewidths. So, any changes that you make in the injector deadtime will affect idle twice as much as it will affect cruising. But, yes, it will affect both if they are both in the same V range that you are adjusting for.

DSMLink used a global fuel setting slider and then an injector deadtime value to tune the injectors. Their global slider was basically the injector scaling value in the ECU and their deadtime was basically what we get to adjust in the voltage latency tables.

But, with the years of experience with DSMLink and seeing others dial in injectors, the above holds true.

Basically, what we did with DSMLink is as follows:

1. Choose a global setting (ECUFlash injector scaling number)
2. Log trims at idle and cruise
3. If trims are roughly the same, but positive, then you need to increase your global fueling, or in terms of ECUFlash, you need to lower your injector scaling number.
4. If both trims are roughly the same, but negative, then you need to descrease your global fueling, or in terms of ECUFlash, you need to raise your injector scaling number.
5. If idle trim is more positive than cruise trim, then you need to increase the dead time, or in terms of ECUFlash, you need to increase the latency value.
6. If the idle trim is less positive than the cruise trim, you need to decrease the deadtime, or in terms of ECUFlash, you need to decrease the latency value.

Note: After #5 or #6, you may need to readjust #1 accordingly.

Note 2: #5 and #6 implicitly answer ludikraut's questions about affecting idle and cruise trims. Basically, let's say that the IPW is 1ms at idle and 2ms at cruise. If you adjust the deadtime to add 100us (.1 ms), then you are affecting the idle fueling 10% and the cruise fueling 5%.

smartbomb
12-24-2007, 04:14 PM
Try these...

Scaling=860

Voltage----ms
4.69---------3.312
7.03---------2.184
9.38---------1.560
11.72-------1.080
14.06-------0.744
16.41-------0.480
18.68-------0.312


I ended up using this:

Scaling= 860

Voltage….ms
4.69……..3.312
7.03……..2.184
9.38….....1.560
11.72…...1.008
14.06..….0.696
16.41……0.408
18.68……0.336

Now my long terms trims are within +- 5%. The idle quality is now decent, not excatly as smooth as stock but pretty good and a huge improvment ovwer what I started with.

Thank you for your help!

AWDTURBO
01-31-2008, 10:52 AM
^^ I used the same setting last week when i swapped out my 680cc.

After I flashed and started it up. It idled very nicely! I was suprised! I didn't stay much longer to check my fuel trims. I will get back to that when i get the car back from the body shop whenever that is now....damn quarter panel extension is on nationwide backorder for 2weeks-1 month. =*(

LBEVOGSR
01-31-2008, 11:29 AM
Damn Lawrence get that car already! Lol.

AWDTURBO
01-31-2008, 01:59 PM
i know fukin sh*t that part has to be the rarest part on the evo or something.......sighs....

neways did u put those 1000cc in? how does the car run?