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Old 02-23-2016, 03:36 PM   #41
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Originally Posted by Mentalbiker12 View Post
They way I adjusted for the fuel pressure was in the calculated fuel. I found a calculator online for difference in pressure and set injector size to the appropriated value I got which was somewhere around 530cc I believe
where did you do this? this is not something you need to worry about.

use the injector sizing as rated at 43.5psi.
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Old 02-23-2016, 03:47 PM   #42
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id leave the DT value as it was, but use the updated correction curve. .6xxx ms just seems WAY too fast, especailly when you compare to what FI stats for their injectors.
OK, I've got the correction curve set to what you suggested. Please see the thumbnail for details. So we're sticking with that, right?
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Old 02-23-2016, 03:53 PM   #43
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you mean like overrun settings?
Yes, this is set in the overrun menu.
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Old 02-23-2016, 04:08 PM   #44
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2sec is pretty good, that way you dont cut fuel too fast.

this is normal, there's no need to inject fuel while the rear tires are spinning the motor for you.
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Old 02-23-2016, 04:24 PM   #45
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OK, that's good to know. Still, I was hoping that setting would stop the behavior where the AFRs go way lean when I let off the throttle while I'm shifting gears. It didn't work out that way.

Maybe the next step is to play with the idle screw and recalibrate the idle valve. Then we can see how things are going.
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Old 02-23-2016, 05:54 PM   #46
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OK, that's good to know. Still, I was hoping that setting would stop the behavior where the AFRs go way lean when I let off the throttle.
I don't understand why you feel this is a problem. The only way I can think of not seeing lean values without throttle input would be in some sort of anti-lag system. I am amazed at all the help you have gotten, honestly.
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Old 02-23-2016, 05:59 PM   #47
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OK, that's good to know. Still, I was hoping that setting would stop the behavior where the AFRs go way lean when I let off the throttle while I'm shifting gears. It didn't work out that way.
it shouldnt between shifts really.

at least not that you'd notice.

could be aggressive (read: poorly tuned) launch control settings, and/or poorly tuned throttle enrichments.
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Old 02-23-2016, 06:13 PM   #48
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Fwiw, I go lean between shifts with begi reflashed ecu + xede. Up to 16-17AFR. Any higher or if I'm getting on it bogs the car till more fuel comes in

Probably not related as I'm a special snowflake.
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Old 02-23-2016, 06:19 PM   #49
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I don't understand why you feel this is a problem. The only way I can think of not seeing lean values without throttle input would be in some sort of anti-lag system. I am amazed at all the help you have gotten, honestly.
Well, I'm sure grateful for the help. I realize that people, and especially Braineack, are helping with some basic mistakes. So I appreciate that I'm coming across as clueless, but that's largely because I'm having to learn everything that was done previously and figure out what's correct. I'll sure take responsibility for when I'm actually clueless. Meanwhile, I'm looking for somebody who can help me in detail with my tune. I'm talking with Curly about taking my car to his shop in Oregon but I'd like to stabilize things enough to get it down there.

Anyway, you're saying it's expected behavior for the AFRs to go full lean after I let off the throttle? I'm asking about that because that didn't happen before we made all the changes on Sunday. I'll let go of this if it's nothing to worry about.

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Old 02-23-2016, 06:23 PM   #50
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where did you do this? this is not something you need to worry about.

use the injector sizing as rated at 43.5psi.
FWIW, I put a fuel pressure gauge inline to test the pressure myself. I'm seeing bang on 43.5, which is expected by the Flow Force injectors. Figure I should change back the spot where Mentalbiker12 configured them for 556 because he saw low fuel pressure instead of the 610 they're intended to be. Does that sound right?

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Old 02-23-2016, 07:17 PM   #51
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Originally Posted by aceswerling View Post
Anyway, you're saying it's expected behavior for the AFRs to go full lean after I let off the throttle? I'm asking about that because that didn't happen before we made all the changes on Sunday. I'll let go of this if it's nothing to worry about.

So I went back through my logs and I go pretty lean between shifts as well. On a WOT pull I go from high 9's/low 10's to high 13s/low 14s. This is within .9 of a second. There is even a slight lean spot at 100% TPS which I assume is the lag at which the O2 sensor picks up the change in Lamda. Once you start tuning Accel enrichment you will see changes in these areas of the graph.

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Old 02-23-2016, 07:17 PM   #52
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If you are gettin 43.5 psi then yes. The injectors were flow tested to 43.5 at 620cc. So give that a shot
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Old 02-23-2016, 08:15 PM   #53
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Cool. I went ahead with that change and everything is working much better combined with a bit of autotuning. Glad we figured that one out.

I also adjusted the idle screw and valve so both of those are improved too.

Finally, I increased fuel in the bottom row of the VE table and the AFRs aren't going lean like they were before. It appears this was happening through a combination of overrun fuel cut and that row being too lean.
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Old 02-23-2016, 08:31 PM   #54
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Ok. I remember having no to make a change there on mine to but for the opposite reason. My shifts were dropping into the 9.0 afr range on minimum load and causing a lot of shuddering.
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Old 03-12-2016, 09:42 PM   #55
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So Ace ended up bringing the car to me after some email discussions. I figured since this issue started with open sharing, I might as well continue it by sharing his current tune.

First off, I did NOT look at his original tune long enough. Too many things taken for granted, and wow were some of the tables messed up. Braineack covered most of those in this and the original thread, so I won't get into that too much.

Along with FF's updated dead time, the car starts and drives beautifully, I just need to double check cold cranking duty and cooler WUE.

Attached is the dyno (**** you photobucket!!), the lower numbers were just autotuned and wastegate, higher numbers are what I finished at. His 5-speed sounds like it's supercharged, so along with that and the stock block I didn't want to push too far past 240ft/lbs.



Also I thought this was an interesting comparison. The lower numbers on this graph is a freshly built '96 M-edition with a older FM kit and a rebuilt (bigger compressor wheel) 2554. It has .25 overbore, [email protected], no cat, MS2pnp and the same intercooler. The higher numbers is Ace's '95 M-edition with his newer FM kit, [email protected] and 2860.



Also attached is a log of the #25 dyno pull and his .msq. Feel free let me know if you see anything fishy, but like I said it seems, as of now, to drive quite well!

Only issue on the dyno was a little blowout from his Fab9 COP kit. We fixed that with a smaller gap (.026"). Dwell was also turned down from 3.5 to 3.0, not sure if that made any difference though. Looking at the rpm trace again there's some choppyness I'm not 100% happy with. Any bigger and I probably would of felt that on the dyno...

As always, a huge, HUGE thank you to Kris Osheim at KO Racing for his wonderful help and his wonderful DynoJet. This tune wouldn't be half of what it is without his input. If you're ever in the pacific NW area and need a car tuned, go to him. When he says how much it'll cost for a full tune, drop your jaw and say "that's it?!?!".
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Warm restart and idle issues-80-aces_before_after_2afb7ee179b555cfe99b96547ffb16bb35d77756.jpg   Warm restart and idle issues-80-wann_vs_ace_4b8520d8c7ad27c350522cc9cde816a9c06a71d2.jpg  
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File Type: msq Ace's tune.msq (243.3 KB, 56 views)
File Type: msl dyno run 25.msl (590.5 KB, 34 views)
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Old 03-12-2016, 09:52 PM   #56
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I'm glad everything worked out for you ace.
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Old 03-13-2016, 12:12 AM   #57
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i dont know how changed the tune got since the last time i made any adjustments to it but it seems as if everything got sorted, what exactly was off with the timing tables? im hoping to learn from all this so that i may grow as a tuner
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Old 03-13-2016, 03:18 AM   #58
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Here's a visual.

The following NOT an ignition table.

It is a subtraction of my table from your shop's table.

Now I did tweak a few of the lower RPM column values, (because you should usually have a column at your target idle and what the hell do I do with a 700rpm column?) but basically I tuned to MBT (or as close as you can without a knock sensor) by decreasing timing to make sure a significant loss in power was detected, and then increasing until power wasn't made. Keeping timing when it worked, returning to lower values where it didn't.

I could increase timing a few degrees without knock if I wanted a more aggressive tune, so lets say that, maximum, the "best" table should within ~5 degrees of mine. It's impossible to get in the upper left cells, and improbable that you'll ever be in the lower right cells, so they can be ignored.

THE MOST IMPORTANT CELLS are the upper mid to upper right cells. Those are the boost cells. Look at the numbers in the table below. Why are they so high??


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Warm restart and idle issues-80-comparison_ignition_table_83ea1a975d93ae1212ff07b4861c4ea3b62f4d08.jpg  
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Old 03-13-2016, 03:23 AM   #59
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Unfortunately I can't give a complete answer. My boss who did the tune set timing through the megasquirt rather than physically or something to throw off anyone trying to look at the tune. I tuned the cruising cells and worked on cold start warm start type tables. Only thing I tuned for boost was boost control duty table. The timing table I brought down ~15* from what they were before. After that ace checked base timing and adjusted to set it correctly from that side. After that I had not done any tuning. So that may possibly have played a role to the drastic difference.
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