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Old 09-12-2015, 03:01 AM   #1
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Default VE values too low?

Hey guys,

Bit of a newbie, but I've got a few questions about tuning via Megasquirt. I think I've got most things pretty good, it's running decent, but I did have a few questions.

My first question is regarding some low VE numbers in my table. I started with the base map provided by Brain (Thanks again), tuned my injector dead times based on the forum post here (Strange Results of Injector Change), finally calibrated my battery voltage to the injectors which helped things, but I'm noticing my VE table numbers seem low compared to others. My req fuel is currently 4.1 (running DW700 injectors) and I'm hesitant to drop it lower as that seems to cause higher cells to start running a bit lean, but the numbers near idle do seem low. Should I care? Am I losing resolution by not having these numbers around/above 30's?

Car Details:
93 Miata
94 Engine (1.8 swap, complete with TPS, IAC, etc)
DW700 injectors
FMII Turbo Kit (GT2560)

My next question is regarding acceleration enrichment. I think most of the instructions on acceleration enrichment have to do with an older version of MS, TunerStudio, or both as it's a bit unclear as to whether or not I'm using TPS or MAP enrichment or not. I think I need to increase my acceleration enrichment as I do seem to be going a little bit lean when I hit the gas, but maybe I'm worried about nothing.

My last question (for now anyways) is regarding wiring for sequential injection. I understand the basics, but I'm trying to avoid running more wires through the firewall if I can help it especially since I have a bunch of spare wires from things I removed (purge solenoid, power steering wire, also did a coolant reroute so I blocked off and deleted the front coolant thermo switch). I'm wondering if I can use 2 of these wires for my sequential injection, or are these wires too small? I'm guessing if I pick wires too small I'll see a voltage drop that could cause issues (maybe the voltage drop may mess with the dead/opening time?)

<a href=""><img src="" title="source:" /></a>

I'm also not running an idle VE table at the moment because I'm not quite sure I need one or what the exact purpose is (I know, it's a ve table referenced during the idle state, but why that's different from the standard VE table is a question), but I can probably do some reading and figure that out...

I've also attached my tune. Any advice is appreciated, thanks guys!

Here's a log from a drive I took a little bit ago (though I did modify my VE tables just a bit since then to smooth some things out):
Attached Files
File Type: msq ForForums.msq (231.5 KB, 58 views)

Last edited by compuw22c; 09-12-2015 at 03:10 AM. Reason: Added my log
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Old 09-12-2015, 12:03 PM   #2
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looks about right to me. ID injectors will typically have values double what youre seeing at low loads since they cycle so much faster.
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Old 09-12-2015, 01:26 PM   #3
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Awesome, thanks again man. If anyone has any advice regarding accel enrichment or experience with the sequential wiring reuse I'd appreciate it. Thanks!
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Old 09-12-2015, 05:21 PM   #4
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No, nothing in the harness is proper for running injector sized currents. You don't want different wire gauge for different injectors, that's a recipe for a bad time. It is easy to run two new wires, I wouldn't jack with anything else.
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Old 09-12-2015, 07:42 PM   #5
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your map looks pretty good to me. I agree with Brain, your deadtime might be a ~little~ high which sneaks into the low load cells like that. My IDs idle around 55%, but I have a fair amount of head-work.

There are a couple of fairly decent threads here for EAE, which is the shizznit when you get it working right. I run a 2 squirt configuration due to large injectors, but have played with 4 squirt and it does work better.

Short version ...
Start by setting all of the RPM and CLT tables to 100 to disable them. Pick an RPM that you can sustain for a decent amount of time on a stretch of road that allows you to pay attention to your wideband. The method I worked with was basically:

- with an increase in engine load ->
-- just lean means decrease adhere at starting (low) load, decrease sucked at ending (high) load
--just rich is the opposite
-- lean followed by rich means decrease adhere at starting, increase sucked at ending
-- rich followed by lean means increase adhere at starting, decrease sucked at ending

-with a decrease in engine load
same as above, but with high/low load swapped (start/finish)

it is easier, but takes longer if you only adjust one of the two tables at a time.

I could have just lucked into something that appears to work fairly well though.

The RPM you were working with stays at 100
choose other RPMs around that point and adjust the RPM tables moving forward
Then work out the CLT, which is hard to get data. I don't even adjust with CLT (still at 100)
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