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Old 09-30-2011, 07:12 PM   #61
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vs. voltage you mean? If so, I agree.
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Old 09-30-2011, 07:20 PM   #62
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Quote:
Originally Posted by JasonC SBB View Post
vs. voltage you mean? If so, I agree.
Yes sir.
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Old 10-16-2011, 08:08 PM   #63
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This was a log today with the dead time set to .734 at 13.2V and it suggests use a deadtime of ~ .95



I took another log with the deadtime set to .95 and the plot shows a linear fit at .85

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Old 12-16-2011, 08:40 AM   #64
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Does anyone know what is the maximum capacity of injectors that the stock ECU can manage? eg. 370cc, 440 ?? etc. My car is a nbfl 2002 1.6
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Old 12-18-2011, 01:56 PM   #65
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Nobody knows??
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Old 09-07-2012, 07:59 PM   #66
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Hi guys!!!

It is sort of a long story but I just became aware of this thread while looking into my new tune after switching to 1.8 tan injectors.

A little background information .

1.6 @ 6.7 psi of boost with a walbro, tan 1.8 injectors and a MS 1

Yes, I am getting the oscillations occasionally.

Yes, the old lap top failed last night so my questions are in preparation for any tuning or changes that I might do

After the swap the motor started up with the 1.8 injectors but ran rich.

We changed Required Fuel to get the fuel in the ball park and retuned from there using Autotune.

Logs showed that injectors had a larger margin of safety duty cycle etc compared to the 1.6 injectors and no lean spots were observed under boost.

Q: What am I leaving on the table if I just leave my settings where they are, like the 1.2 ms injector delay. ?

Thanks!
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Old 09-08-2012, 12:00 AM   #67
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With the brown 1.8 injectors i ran .64 at 13.5 volts (forgot which voltage ms uses)

64 at 13.5volts
63 at 14volts

1.2ms is a big difference vs .63-.64.

What you're leaving on the table is a whole lot of stability. Personal story... My car could barely start all winter because Travis missed a decimal when he tuned my car... long story short he put a .13ms delay when there should have been 1.3ms delay so during cranking the fuel all over the place varying with the voltage of the battery.

My car would lean every time I lift the windows, my car would lean every time my fans turn on... and usually die at a light which then made the problem worse since remember the cranking problem? Now the car has freshly charged battery and its spitting a lot more fuel...not wanting to start because now the mixture is now too rich and people dont really like waiting for you to start your car for 4 minutes of cranking at the lights especially during rush hour.
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Old 09-08-2012, 02:40 AM   #68
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Wow! That is wild!

Wich I had my lap top so I could tell you all the parameters besides the 1.2ms

My car is running fine however (?)
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Old 09-08-2012, 03:32 AM   #69
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Well my problem was such a big deal because i'm running 800 cc injectors... 1 ms difference on a 240 cc injector is not that much.. 1 ms difference on an 800 cc injector will flood your ****. Now just because its not much doesnt mean it wont affect it.. it will run better with stuff correct.
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Old 09-08-2012, 12:15 PM   #70
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Quote:
Originally Posted by triple88a View Post
Well my problem was such a big deal because i'm running 800 cc injectors... 1 ms difference on a 240 cc injector is not that much.. 1 ms difference on an 800 cc injector will flood your ****. Now just because its not much doesnt mean it wont affect it.. it will run better with stuff correct.
I hear you.

They 1.6 and 1.8 are not very different and this is probably why/how I'm getting away with it.
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Old 09-08-2012, 01:32 PM   #71
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Well it makes no sense to me why you wouldnt correct it.. you're running an MS and the only thing you gotta change is that value.
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Old 09-08-2012, 01:41 PM   #72
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Quote:
Originally Posted by triple88a View Post
Well it makes no sense to me why you wouldnt correct it.. you're running an MS and the only thing you gotta change is that value.
Oh, I am going to it is just that I have no lap top right now.

U think it needs to go up or down ?

I think I will need a paid version of Megalog Viewer to follow the method described and that will be yet arother expense and delay.

Maybe I can try the old trial and error.

Thanks,

P
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Old 09-30-2012, 03:16 PM   #73
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Ok this is what I did ...

Reduced the inj dead time from 1.2 to 1 and asked MLV autotune function to tune the AF on the lower KPA cells - idle and just off idle.

It took one cell and raised it to the max that the advanced filter would allow
I had to go back to a saved copy of the same MSQ .

What did I screw up ?
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Old 11-24-2012, 11:35 AM   #74
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What kind of dead times do you **** expect with EV6 and EV14 injectors? I want to make sure I have reasonable numbers when I start doing this ****.
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Old 03-03-2013, 04:07 PM   #75
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Necrothread, arise!

Can anyone take a look at my junk and point me in the right direction for injector dead time? I've attached a spreadsheet with the relevant datalog info, including data limit cells to adjust what is displayed in the graph.

I had initially set a dead time of 1.48 based on the published specs, but it's been suggested that this is too high. Anyone care to share their expertise with me?

Quote:
Originally Posted by Published Specs for DeatschWorks 22S-00-0350-4 injectors
Fuel Pressure Correction
PSI - cc/min
30.0 - 304
35.0 - 329
40.0 - 351
43.5 - 366
45.0 - 373
50.0 - 393
55.0 - 412
60.0 - 430
65.0 - 448
70.0 - 465
75.0 - 481
80.0 - 497

Latency Data (@ 43psi)
Volts - Millisec
7 - 3.3
8 - 2.6
9 - 2.2
10 - 2.0
11 - 1.8
12 - 1.6
13 - 1.5
14 - 1.4
15 - 1.3
16 - 1.2
17 - 1.1
Attached Thumbnails
How to find your injector dead time-dw350plot3.jpg  
Attached Files
File Type: xls 2013-03-03_idle-deadtime3.xls (1.17 MB, 131 views)
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Old 03-11-2013, 12:53 AM   #76
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Anyone? Got any suggestions on my dead-time or at least how to get a cleaner data plot?
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Old 03-11-2013, 10:31 AM   #77
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What's wrong with .94? If 1.48 was too high, I'd guess .94 is probably pretty close.

I know nothing about this, but that seems reasonable considering the other results in this thread. Also it looks like a decent fit for that graph. I guess if you are really worried try again and take another log.
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Old 03-27-2013, 01:17 PM   #78
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FWIW, I should probably update this thread with my results. I still had some issues even when dropping the dead time to 1.13 (which was my best fit for the line, visually, after trying to eliminate some of the noisy data), so I sat down and gave it a good long think. I decided that the published injector times are probably correct and that much of my problems stemmed from the injectors being unable to cycle quickly enough to idle steadily at 14.7:1. So I reset my settings back to the published specs and let the car idle around 12:1, re-tuned the fuel map, and so far everything is looking pretty stable. So basically, these injectors just have horrendously slow latency times. For now I will let it idle rich, but I may be looking for different injectors before too long because that's kind of ridiculous.
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Old 03-27-2013, 01:24 PM   #79
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Thanks for sharing this. I appreciate it.

I also left my settings as they were. Basically I was trying to play with them for no other reason than because others had done so but never really put in the time to understand what I was doing.

I had gone from stock Miata 1.6 injectors to stock 1.8 injectors.
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Old 03-27-2013, 01:26 PM   #80
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lol at having to idle at 12:1 with slightly larger than stock injectors. DW injectors are awesome!
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