Blackbird Rush
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| posted on 31/12/09 at 04:22 PM |
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Megasquirt pointers
HI,
Well had my MS1 V3 install (fuel only) running at idle today, i'm slowley working my way through the Megamanual and next step is to start
tuning.
The engine idles and runs way rich and is a bit lumpy, it also dies a little when you rev it up, presumably these will sort them selves out during the
tuning process, any pointers to where to begin or tips from those who have gone this route before?
I'm running the std code set up for fuel using the bbird's original ignition box for sparks.
cheers
Ash
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flak monkey
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| posted on 31/12/09 at 04:28 PM |
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I assume you have a wideband lamda fitted and working?
I would hazard a guess that when you rev it and it dies that its too rich. I would scale the VE table down a little to get you at a more reasonable
starting point.
Then its just a case of datalogging while driving and iteratively improving the map. I was still tweaking my pinto one when I took it out, 6months
later. Was pretty much spot on by then though.
You want to be aiming at 12.5 AFR at WOT at all engine speeds. And 14.7AFR at idle and cruising. The about 13.5-14 under moderate acceleration. Make
sure your target AFR table is filled in.
David
Sera
http://www.motosera.com
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gregs
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| posted on 31/12/09 at 04:39 PM |
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as flak says - getting it running at a reasonable idle as close to stoich as you can - without getting this you've got close to zip chance of
tuning it.
Personal preference, but I use a combination of req fuel and adjusting the regulator to get what I'm looking for.
If you are using a standard setup on your bird engine, then I'd be asking elsewhere for a map - won't be plug and play but will be a
better start than the guesstimate megatune will come up with!
[Edited on 31/12/09 by gregs]
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fatbaldbloke
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| posted on 31/12/09 at 06:52 PM |
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These comments reflect my experience, I'm sure others will have found their way around the challenge in different ways. What I would do is set
AE way out of reach. Don't worry about it until you have decent steady state running. Personally I wouldn't worry about what the AFR is
at idle either. Just set the fuel table around idle so it idles best and if you're using closed loop set the idle rpm outside the lower rev
limit so it doesn't try to correct itself to a target AFR.
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Blackbird Rush
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| posted on 31/12/09 at 07:27 PM |
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HI Chaps, thanks for the feedback....
Yes, have a wideband LC1 fitted, it seams to be working, did the calibration set up and the led displays that its functioning correctly, i get a o2
votage reading in the megatune it was up & down from 0-4v!, think i'm aming for a reading of 2-3v ish to give the correct AFR.
Unfortunatly as the car is unregistered i cant pop off for a drive to datalog, so all i can do at the mo is tweek away so it runs well enough (and
clean enough) for the IVA test (not booked up yet).
Pretty sure i have filled in all the constants and target AFR (14.7), there are 2 things i need to do first, 1. change the settings in megatune so the
display shows the correct range on the rev counter for a bike engine. 2. use easy therm to create a config file for my coolant temp sender. (do i need
to do this for my air temp sender as well?)
I have a map from another LB'r for a blade engine, however i have run this previously and then had fuel pump issues (fried transistor) so
i'm not sure if this map had anything to do with it? so i'm being cautious and building a map from scratch, so far so good.....
Cheers
Ash
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matt_gsxr
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| posted on 1/1/10 at 05:53 PM |
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Nice one.
Its a good feeling getting it going isn't it.
My experience with GSXR1100 engine is that it doesn't like a 14.7 at idle, although it can maintain it for a while it prefers 13.5 or so. I
guess you will need to be near stoich to get through IVA, so (if I were you) I would aim for 14.7 at 2000rpm, but a bit richer at the normal idle
speed. That should make it drivable.
Also for IVA it needs to rev to 75% of max power RPM without any miss fires (missfires will mess up the noise test!). Missfires are also confusing
with the lamba probe as rich missfires leave oxygen in the exhaust and so appear to be lean.
If you could drive about then it would tune up really fast, but as you can't its more tricky. Any chance of using the "works
carpark" or equivalent? You will be amazed how quickly the LC-1 and logviewer can sort out the map at least to a rough and ready level. I
wouldn't turn EGO on, as it can get confused when you have a very poor map.
I didn't know you could damage the MS transistors with the msq (for your fuel pump), but it isn't difficult to transcribe from one msq to
another by hand and that is a safe thing to do.
Here is a link to my experiences, not all that complimentary of my abilities I am sorry to say.
my experiences link
All my experiences are with the MS1 Extra code, and I have just started using the ignition functionality of the MS unit, which was a real faff to get
going.
Are you going to drive to IVA, or trailer? If driving then you will need to "map on route". By this I mean drive a bit whilst logging,
and then update the map. Otherwise you might have a load of flat spots and might foul the plugs (and make the emissions a bit tricky).
Exciting times,
Matt
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