RazMan
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 posted on 20/3/11 at 12:05 AM |
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Easimap Question - entering negative values
In an effort to reduce my tickover speed (my butterflies are not sealing perfectly) I want to input a negative ignition value in the map. I can change
the graph display limits to show a neg side of zero, but I can't seem to enter a neg value (ie minus 2 degrees) The help file tells me to enter
[= - 2] but every time I hit enter it just defaults to zero 
Has anyone a clue as to what I am doing wrong?
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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ashg
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| posted on 20/3/11 at 08:41 AM |
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you shouldn't really be running less than 8deg at tick over going into negatives is really far from ideal as it will make your exhaust red hot
as well as your exhaust valves which will eventually fail and kill the engine. you really need to work on the butterflies as trying to work around
them will end up in tears.
[Edited on 20/3/2011 by ashg]
Anything With Tits or Wheels Will cost you MONEY!!
Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)
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RazMan
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| posted on 20/3/11 at 09:25 AM |
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You are quite right of course, but I have tried 3 times now and can't seem to get a good enough seal - and with 12 butterflies to fettle it
takes all day! I even used some special sealing compound around the butterflies (that manufacturers use to help with this problem) and initially had a
good tickover without too much tinkering but after a few days of mapping it has drifted out again.
Is there a 'how to' guide out there to show the butterfly fettling process ? I just can't seem to get it close enough
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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matt_gsxr
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| posted on 20/3/11 at 09:35 AM |
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I don't know the details of your ignition.
But as you get more negative you will be decreasing the time between the triggering tooth and the time of the ignition spark.
At some point you would be trying to fire the ignition before that tooth, which would be impossible (non-causal). Before you get to that impossible
point you would be sensitive to processing speed, as the ECU will need some time between the tooth and the ignition to do some calculations.
This is only based on Megasquirt experience though.
Another option to decrease the idle might be to run on a reduced number of cylinders at idle. Just a thought, but it would also save fuel (I
believe). With Megasquirt I think you could use staged injection settings to bring the other cylinders in. Just a thought, I've never tried
it.
Matt
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RazMan
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| posted on 20/3/11 at 10:07 AM |
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quote:
Originally posted by matt_gsxr
Another option to decrease the idle might be to run on a reduced number of cylinders at idle. Just a thought, but it would also save fuel (I
believe). With Megasquirt I think you could use staged injection settings to bring the other cylinders in. Just a thought, I've never tried
it.
Matt
That's an interesting idea, and one which might be explored soon if I can't do it with the timing method. However I havent a clue how to
cut out a cylinder (or bank) in my ECU settings. (It is an MBE 970 on Alpha-N) I don't think it will save fuel though - the injectors will
surely be squirting all the time regardless won't they?
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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rusty nuts
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| posted on 20/3/11 at 11:37 AM |
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Just a thought , would it be possible to run at just under 360 degrees advance at idle ? It would be the same as running retarded if you are using
wasted spark
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matt_gsxr
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| posted on 20/3/11 at 07:58 PM |
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quote:
Originally posted by RazMan
quote:
Originally posted by matt_gsxr
Another option to decrease the idle might be to run on a reduced number of cylinders at idle. Just a thought, but it would also save fuel (I
believe). With Megasquirt I think you could use staged injection settings to bring the other cylinders in. Just a thought, I've never tried
it.
Matt
That's an interesting idea, and one which might be explored soon if I can't do it with the timing method. However I havent a clue how to
cut out a cylinder (or bank) in my ECU settings. (It is an MBE 970 on Alpha-N) I don't think it will save fuel though - the injectors will
surely be squirting all the time regardless won't they?
I don't think you'd want to be squirting fuel and not burning it. You would stuff your emissions and catalyst and also wash all the oil
off the bores which would not be good.
The way that I would implement it would be to run batch fire but have two sets of injectors. One set would always get fuel and be your
"idle" bank, the other set would only get fuel when you were above a certain level. If your ECU can handle staged injection then this is
exactly the same thing, staged injection would normally be used to bring in a separate set of ADDITIONAL injectors, but I don't see why it
couldn't also work in this way. The only problems would be, AFR wouldn't be true as half the cylinders would be pumping air, the
transition might be challenging, you would have to manage the transition and inevitably when you first bring the injectors back in you will be a bit
lean (the inlet manifold will have had all the fuel washed off it).
I think it could save fuel (I think one of the big US manufacturers does a trick of this sort on their big v8's, probably a bit cleverer than my
method), actually here's a link:
http://www.jdpower.com/autos/articles/Engine-Cylinder-Deactivation
-Saves-Fuel/
The more recent systems actually leave all the valves shut, but if you have ITB (and I know you have  ) then cutting the fuel to a few cylinders
might be an answer.
Worth a read anyway!
Matt
[Edited on 20/3/11 by matt_gsxr]
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RazMan
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| posted on 20/3/11 at 08:18 PM |
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quote:
Originally posted by rusty nuts
Just a thought , would it be possible to run at just under 360 degrees advance at idle ? It would be the same as running retarded if you are using
wasted spark
I like your logic and almost had a Eureka moment .... but sadly Easimap won't allow anything over 60 degrees in the map.
Matt, I think the staged injectors idea, although very innovative, is probably too complicated to warrant trying it. If I am honest with myself, maybe
I ought to have yet another go at sealing the butterflies a little better. This would save all of the jiggery pokery and probably be the more sensible
solution. My tickover is currently about 1400 rpm but it certainly runs quite hot due to the amount of ignition retard I am forced to run.
Thanks for all the ideas guys 
[Edited on 20-3-11 by RazMan]
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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matt_gsxr
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| posted on 20/3/11 at 09:10 PM |
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Agreed, the best solution is normally the simplest.
I might have a play at reducing cylinders, just because its there!
Need to get my engine fixed first though.
Matt
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RazMan
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| posted on 8/4/11 at 06:52 PM |
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Update:
With some careful application of some more Molybdenum Dry Film Lubricant I have now got the tickover right down and can advance the idle timing back
to normal levels ...... but what exactly is normal for the Duratec V6?
All of the Easimap demo maps seem to have 0-2 degrees (but they do seem to be fairly crappy) and I have brought it up to about 6 degrees now and
things appear to be much more stable - even had to tweak UP the idle screw a bit! I will obviously get it properly mapped eventually so I'm just
playing with idle quality at the moment.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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matt_gsxr
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| posted on 8/4/11 at 10:18 PM |
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Well done in sorting that out. It was always going to be the best solution, but the tolerances are pretty challenging.
Regarding idle advance;
In the Dave Walker book he says 10deg. Not specific for any engine.
Too high and the throttles are really closed and its difficult to manage the first bit of opening.
Too low and everything gets a bit hot and you waste fuel.
but you know that already.
As long as it idles in hot weather without overheating, the emissions pass the MOT, the idle is sufficiently slow and stable, and the throttle roll-on
from idle works, then I would say it doesn't matter about the exact figure.
nice work,
Matt
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RazMan
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| posted on 8/4/11 at 10:47 PM |
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It's the roll-on from idle that has been my major challenge - a kind of 'all or nothing' feeling. Initially I had the AFR all wrong
and it was like turning on a switch but with some careful mapping it is now much easier. I have left it at 6 degrees for now and it seems to have a
nice pickup at small throttle openings with a fairly good AFR (about 13.0)
I might still need to work on a more progressive throttle setup though - I keep leaving lots of rubber on the road unintentionally 
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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matt_gsxr
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| posted on 8/4/11 at 11:08 PM |
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I struggled with this when I first fuel injected mine.
I had a few problems;
Poor mapping down at the bottom
Poor balancing
TPS wasn't seeing the small changes in throttle position
One trick than someone from here (Mike perhaps) was a parallel resistor with the TPS which increases the sensitive to small changes. This was worth
the bother with MS1, which has poor TPS resolution, but I don't think its relevant to you.
If all your throttles are perfectly balanced, then you could drop the advance a bit above the idle, that would stabilise the idle and reduce black
lines.
On my engine (bike, so wet clutch) I tend to slip the clutch a bit at slow speeds.
Matt
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RazMan
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| posted on 8/4/11 at 11:19 PM |
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The throttles are basically all on a common shaft so no adjustment is possible - its about as good as it will ever be The resolution is pretty good
and goes from 0.43v to 3.98v. Easimap had map sites at every 250rpm so no problem there.
quote:
If all your throttles are perfectly balanced, then you could drop the advance a bit above the idle
Do you mean a gentler slope? I have already extended the base line to 1750rpm - should I go any further with the next TPS positions maybe?
Would you mind having a look at my idle map and see what you think Matt?
 
Sample Map
TPS position for reference
Red - 0
Yellow - 1
Green - 2
[Edited on 8-4-11 by RazMan]
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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ashg
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| posted on 9/4/11 at 07:26 AM |
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to get it to move off of idle nicely you need to come off of idle settings around 1300rpm. not sure how is done on your ecu but my idle fuel and
spark table stop at 1300rpm or 3% throttle opening and then use the main table. the tricky part i found was moving from the idle table to the main
table without funny behaviour mine is now perfect accelerating and moving away off idle but it sometimes has a funny jurk now and then coming back
down from above idle say 3000rpm in heavy traffic.
does your ecu have any data logging facility? usually i go out with an sd card in mine and try and log only the strange behaviours using the log
on/off button i have tucked under the dash. if you cant do that does the laptop software log? its much easier to log the event and look back at it
afterwards to make the changes.
for idle speed i would go for a touch under 1000rpm, fix the air and advance 8-10deg around the rpm/load it idles. then set the advance higher in
bins below 900rpm. that way if the revs drop the extra advance in the lower bins should bring it back up rather than stall.
Anything With Tits or Wheels Will cost you MONEY!!
Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)
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RazMan
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| posted on 9/4/11 at 09:32 AM |
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My MBE 970 has all sorts of functions that I am not using and I am keeping it as simple as possible for the time being. It uses just the single map at
the moment.
I have now increased the advance to 8 degrees at idle and w2ill be going for a road test later - I'll try not to pick up another speeding ticket
this time
On the subject of data logging, I can switch everything on except the Lambda (which is a separate gauge entirely) so I guess datalogging won't
be much of a benefit for me. Which channels would you normally log in a situation like this?
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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ashg
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| posted on 11/4/11 at 11:28 PM |
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its a bit tricky not being able to log afr against the other values. i typically log tps, rpm, pulsewidth, map sensor, advance, coolant temp and
afr.
your going to have to make a mental note of the afr or setup a camera on the afr and rev counter.
when you look at the log you should see the issues reflected in the rpm, you then need to plot the other values against the rpm fluctuation and see
which one is off.
e.g it could be something simple like noise on the tps sensor, but you wont know without logging it.
i still find it hard to believe that you cant connect the wideband to the ecu. have you phoned the manufacturer and asked if there is a way to do it?
Anything With Tits or Wheels Will cost you MONEY!!
Haynes Roadster (Finished)
Exocet (Finished & Sold)
New Project (Started)
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matt_gsxr
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| posted on 12/4/11 at 03:49 AM |
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quote:
Originally posted by RazMan
Do you mean a gentler slope?
[Edited on 8-4-11 by RazMan]
No I actually meant less actual advance (i.e. reduce the advance with increasing revs, before increasing it again).
I don't know whether you have Dave Walkers tuning book, but he shows an ignition table for a K-series which has some very interesting
features.
Matt
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RazMan
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| posted on 12/4/11 at 03:56 PM |
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quote:
Originally posted by ashg
i still find it hard to believe that you cant connect the wideband to the ecu. have you phoned the manufacturer and asked if there is a way to do it?
I did this a while back and the whole process sounds horrendously complicated and connecting the sensor to the ecu is the easy bit!
First you need to first tell the ecu the type of Lambda system you're using, along with a number of settings, (temperature to allow adaptive
mapping, how much fueling can be changed by in one go, that sort of thing.)
You then need to set up a table relating to the voltage that the ecu translates to the actual Lambda value
You then need to set up the target map. Typically, you would put a figure of Lambda 1 in the low rpm/low tps load sites and a value between 0.85 - 0.9
or so in the higher rpm/higher tps sites. (The theory is that you're running at Lambda 1 on low throttle openings, and richer when you give it
some beans).
My brain melted at this point
Another update: Tickover is now rock steady at 950rpm so I'm really chuffed with that. The roll-on is still a bit savage though - I'm
giving myself whiplash pootling round the country lanes and I have to be really careful at traffic lights or it looks as though I'm up for a
race with everyone It is almost like the butterflies are being sucked shut and then wham open under the pressure of putting the gas on again after
a gearchange. This happens right up to about 4k rpm so I am guessing that reducing the advance would not be possible.
I have decreased the accelerator pedal ratio which has improved things a bit more as the pedal now has a longer travel - I might still have to work on
a progressive cam to pull the throttle cable with to improve things a bit more.
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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atspeed racing
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| posted on 13/4/11 at 04:24 PM |
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what is your TPS voltage at 0% throttle? it should be 0.36 @ idle.
if not you will get a "hole" in the map as throttle is opened off of idle.
try removing spark after the idle sites, it sounds as though the engien is racing, or could be a problem caused by the above.
- colin.
[Edited on 13/4/11 by atspeed racing]
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RazMan
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| posted on 13/4/11 at 04:43 PM |
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Hi Colin
My idle voltage (0% TPS) is actually 0.45V and WOT is 3.98V - I have changed the index map to suit these values and was under the impression that as
long as the values matched the index map curve then things should be ok - is this not the case?
I am not sure if you have read my latest updates but everything appears to be running nicely except for the slightly violent nature of the throttle.
It idles now at 10deg and doesn't actually 'race' but definitely needs your expertise when I can get the time off to visit your
emporium but any suggestions would be appreciated at this point.
[Edited on 13-4-11 by RazMan]
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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atspeed racing
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| posted on 14/4/11 at 07:21 AM |
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hi raz
good to hear its running better
you need to make sure that the throttle moves on the main map as soon as throttle is applied. its to do with the transition between its idle state and
main map state. otherwise you end up with a hole that no mapping can get rid of.
what version ecu is yours again???
- colin.
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RazMan
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| posted on 14/4/11 at 05:45 PM |
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It's an MBE 970 and as far as I am aware there is just one map that controls the whole caboodle so no idle specific map, just one for fuel
and one for ignition........ or have I got it wrong?
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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atspeed racing
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| posted on 19/4/11 at 09:30 AM |
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its all on one map yes. this is why tps voltage is critical. especially as you open the throttle off of idle
e.g. opening the throttle, but that map isnt altering until a certain percntage, so not adding desired fuel required. leaving a hole.
have you managed to make it any better?
- colin.
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RazMan
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| posted on 19/4/11 at 04:41 PM |
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Things have settled down a bit more but I am still a bit wary of my quick action throttle so I will probably have to make some more improvements later
unless my right foot finds it's feminine side soon
My Evodash is playing up now so I am trying to get that sorted before Stoneleigh now
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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