Injector scaling and latecy for different injectors.
Jun 17, 2007, 03:33 PM
#182
What Injector scaling would you recommend?
Here are the injector battery comps that I have scaled via numbers only. I pulled the data from the AEMPro software. These should be good starting numbers.
Let me know what you think. I've attached the xls file.
Ivan
Let me know what you think. I've attached the xls file.
Ivan
HTML Code:
Note: PTE780/880 calculated from 680/1000 Offset and scaled to match factory ECU 7v 9.4v 11.7v 14v 16.4v 18.6v Stock 1.680 1.032 0.672 0.432 0.264 0.144 PTE1000 2.186 1.281 0.771 0.458 0.283 0.172 PTE880 2.186 1.325 0.833 0.534 0.351 0.231 PTE780 2.186 1.369 0.895 0.610 0.419 0.290 PTE680 2.186 1.413 0.957 0.687 0.486 0.349 MSD750 2.186 1.302 0.781 0.452 0.256 0.126 RC720/900 2.186 1.518 1.032 0.694 0.443 0.268 RC1000 2.023 1.079 0.641 0.367 0.181 0.049 RC1200 2.186 2.085 1.581 1.060 0.713 0.471 Holey788 1.903 0.952 0.573 0.353 0.193 0.093 HKS1000 2.109 1.189 0.812 0.583 0.382 0.248 FIC650 2.100 1.071 0.633 0.353 0.175 0.044 FIC850 2.031 0.971 0.591 0.334 0.195 0.106 FIC950 2.186 1.220 0.706 0.425 0.274 0.175
Jun 23, 2007, 07:53 AM
#184
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I have a question regarding tuning battery voltage latencies when running larger cams. I am running Denso 660 injectors that flow tested out at 780/780/820/810.
Getting long term low to match with long term mid has been quite a chore. I have dialed in the mid trim using injector scaling while trying to get low trim to match up with latency adjustments. At this point I am at almost .800ms @ 14 volts which seems to be a lot of latency offset for injectors that I would think shouldn't be that far off of stock.
I am curious if the overlap from my 280's at idle are making it impossible to tune the low fuel trim properly, and if so what point do I just call it good? Also, I am running an open element AEM airfilter on a stock snorkel, and I am starting to wonder if I should go back to the stock airbox for tuning in the latency.
Any advice is greatly appreciated.
Getting long term low to match with long term mid has been quite a chore. I have dialed in the mid trim using injector scaling while trying to get low trim to match up with latency adjustments. At this point I am at almost .800ms @ 14 volts which seems to be a lot of latency offset for injectors that I would think shouldn't be that far off of stock.
I am curious if the overlap from my 280's at idle are making it impossible to tune the low fuel trim properly, and if so what point do I just call it good? Also, I am running an open element AEM airfilter on a stock snorkel, and I am starting to wonder if I should go back to the stock airbox for tuning in the latency.
Any advice is greatly appreciated.
Jun 23, 2007, 08:06 AM
#185
I have the same injectors and they seem to be haunted. As you, the low trim is way high if I get the the mid trim on.
I am running small cams, but have a ported head and valves which I thought might be involved.
before I go to far on the latencies I am going to change the fuel map in the idle area.
sorry no help on your specific question about big cams.
so far I've tried scales from 607 down to 522 and in every case the car has behaved well and really didn't need to be refined. But it bugs me so I keep at it.
One thing I did not know is it takes a relatively long time for the trims to move and once they move are affected each time the car goes through warm up.
I am running small cams, but have a ported head and valves which I thought might be involved.
before I go to far on the latencies I am going to change the fuel map in the idle area.
sorry no help on your specific question about big cams.
so far I've tried scales from 607 down to 522 and in every case the car has behaved well and really didn't need to be refined. But it bugs me so I keep at it.
One thing I did not know is it takes a relatively long time for the trims to move and once they move are affected each time the car goes through warm up.
Jun 23, 2007, 12:02 PM
#187
For Denso 660cc try this and see if they work well in your application:
6.12
3.12
1.992
1.272
0.744
0.648
0.408
Scaling: 636
For denso 720cc I use around .888 for 14v with success on most Evo's so you being close to .8XX isn't unheard of since the 660's flow almost as much as the 720's.
6.12
3.12
1.992
1.272
0.744
0.648
0.408
Scaling: 636
For denso 720cc I use around .888 for 14v with success on most Evo's so you being close to .8XX isn't unheard of since the 660's flow almost as much as the 720's.
Last edited by razorlab; Jun 23, 2007 at 12:05 PM.
Jun 23, 2007, 09:21 PM
#188
razorlab, re 660
would those latencies be custom for big cams? I have input your 636.
can you tell me how the extreme voltage numbers work? I doubt the car ever sees anything other than 10 to 15 volts. So the inputs are trends or do they have another meaning.
update, in my case razorlab's suggestion has dialed in pretty close.
would those latencies be custom for big cams? I have input your 636.
can you tell me how the extreme voltage numbers work? I doubt the car ever sees anything other than 10 to 15 volts. So the inputs are trends or do they have another meaning.
update, in my case razorlab's suggestion has dialed in pretty close.
Last edited by nothere; Jun 25, 2007 at 08:56 PM.
Jun 28, 2007, 11:33 AM
#191
It looks like your fuel trims are maxed out, but I'm not sure with that wacky scale that Evoscan comes with, by default.
To save yourself headaches with fuel trims, go and find the correct forumlas (and request IDs) for them. I'm pretty sure Mitsulogger has the correct formulas. If you can't find them, I will post them later.
When you have the formulas correct, it will tell you the percentage of fuel the ECU is adding or taking away. So, for example your Lo trim may be -12%, meannig that the ECU is taknig away 12% to try to maintain a stoicj 14.7:1.
Anyway, even though I'm not familiar with this scale (where 100 is really 0), it looks like your injector scaling and/or latency are qutie a bit off.
Eric
Jun 28, 2007, 12:21 PM
#193
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Thanks, will log it with mitsulogger instead
The injectors are RC750s, scaled to 665, basically the same latency values shown in that chart from AEM for the RC720/900 row
The injectors are RC750s, scaled to 665, basically the same latency values shown in that chart from AEM for the RC720/900 row
Jun 28, 2007, 12:23 PM
#194
It looks like your fuel trims are maxed out, but I'm not sure with that wacky scale that Evoscan comes with, by default.
To save yourself headaches with fuel trims, go and find the correct forumlas (and request IDs) for them. I'm pretty sure Mitsulogger has the correct formulas. If you can't find them, I will post them later.
When you have the formulas correct, it will tell you the percentage of fuel the ECU is adding or taking away. So, for example your Lo trim may be -12%, meannig that the ECU is taknig away 12% to try to maintain a stoicj 14.7:1.
Anyway, even though I'm not familiar with this scale (where 100 is really 0), it looks like your injector scaling and/or latency are qutie a bit off.
Eric
To save yourself headaches with fuel trims, go and find the correct forumlas (and request IDs) for them. I'm pretty sure Mitsulogger has the correct formulas. If you can't find them, I will post them later.
When you have the formulas correct, it will tell you the percentage of fuel the ECU is adding or taking away. So, for example your Lo trim may be -12%, meannig that the ECU is taknig away 12% to try to maintain a stoicj 14.7:1.
Anyway, even though I'm not familiar with this scale (where 100 is really 0), it looks like your injector scaling and/or latency are qutie a bit off.
Eric
Jun 28, 2007, 12:51 PM
#195
<Request LogReference="LTFT_Low" RequestID="0C" Eval="int(.1961*x)-25" Unit="%" Logged="y" Response="2"/>
<Request LogReference="LTFT_Middle" RequestID="0D" Eval="int(.1961*x)-25" Unit="%" Logged="y" Response="2"/>
<Request LogReference="LTFT_High" RequestID="0E" Eval="int(.1961*x)-25" Unit="%" Logged="y" Response="2"/>
<Request LogReference="STFT" RequestID="0F" Eval="int(.1961*x)-25" Unit="%" Logged="y" Response="2"/>
LTFT is short for Long Term Fuel Trim. STFT is short for Short Term Fuel Trim.
This formula will tell you the exact percentages of fuel that the ECU is subtracting or adding to reach a stocih 14.7:1.
So, +10 means 10 % of fuel is being added...-10 means the ECU is removing 10% of fuel. This is MUCH easier when trying to calculate the correct scaling and latencies for your injectors.
Eric