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Murray · Post by **Murray** » Tue Mar 07, 2006 11:57 am

James - good timing

I just came in from the garage where I've been "tuning" my MS.I had to replace the MAP sensor because water condensed in it and froze so that knocked me off for a week.Then I tried and tried but couldn't get the car to start.I pulled the NGK plugs I've been running and put in and old set of Lodges,turned the key and liftoff

I've managed to get my idle MAP down to 40kpa (which I guess isn't bad ?) by adjusting the values in the VE table.Now if only the damn snow and salt would go away I'll get out on the road and do some real tuning.

I hope you get your board sorted out soon.How do you know you've got a "short ?

I can assure you that the feeling of satisfaction on succesful startup makes all the pain worthwhile.I find it particularly pleasing to look at my engine idling smoothly without the dreaded AFM in place.I've had a hate on for that thing ever since I made the mistake of opening it up thinking I could "improve"it.

Thanks again to Steve,Barry and Enzo for your guidance.It really helps to not feel alone when your tackling a job like this one.

I've posted a datalog of today's run.If anybody notices anything weird feel free to comment.

Once I have a solid .msq file I'll post it for anybody else who's doing a 2.5L MSII with low z injectors.

Steve R · Post by **Steve R** » Tue Mar 07, 2006 3:07 pm

Excellent news Murray, glad you got it sorted & the datalog looks much more normal.

Only a couple of suggestions as it looks like you're pretty much approaching the "how it feels on the road" part of the tuning - once the weather improves!

1/ Try using a lot less accelearation enrichment as the datalog pulsewidths go way up high when you blip the throttle. Start with effectively none (the engine will bog as you crack the throttle), add a little at a time until the response becomes instant (if you keep adding more it will bog again). Basically you are looking for the least amount that gives a very responsive engine.

2/ Check the ignition timing... if it's as per the factory settings, add another 4 or 5 degrees, then re-adjust the tickover speed (just like Greg G's tune up suggestions) - that will also bring the tickover MAP reading down further (I can't remember if you're running fuel & spark or fuel only, but it doesn't matter, just move the dizzy if still using the factory spark control)

Other than that - hope you enjoyed the challenge! It'll soon be running better than it ever did on L-jet.

Steve

Murray · Post by **Murray** » Tue Mar 07, 2006 4:10 pm

Hi Steve.Yes for the accel.enrichments I'll probably use the one's in your posted .msq. I'll have to figure out how to go from the v/sec scale used in MSNS as opposed to the %/sec used in MT 2.25.Are you running pure TPS enrich ? I don't see any tables for MAP enrich in your .msq.I was planning to try both and MT allows you to blend the two together.

For ignition I'm currently running the Bosch and have my static advance at 8 deg.btdc.Do you think greater static advance would be beneficial ?Here again I'm hoping to be able to use your spark table when I make the transistion.

I have a couple of questions for you regarding your setup.

1) I notice your running 6 squirts any reason why.I tried and idle was rougher than using 2 squirts.Could this be due to your high z higher capacity injectors ?

2) What are you seeing as an AFR at warm idle ? I'm relying on a NB o2 for now but to obtain a smooth idle at 950rpm.my o2 is very high (.96v)

Steve R · Post by **Steve R** » Wed Mar 08, 2006 2:33 am

Hi Murray

Re accel enrich, the version of MT I'm using translates the v/s into map dot (I don't know the maths of how) so I can't really comment on how to set percentages other than sugest starting from none & working up gradually in say 2% steps until it revs best. I stress I've not done this myself, so it's a best guess really.

8 degrees isn't enough, at 1000 rpm my hot tickover is 16 degrees, so for a 2.5 with stock cams I'd try 12-14. I'd say Greg G's tune up tips are spot on for the best static ignition settings on a stock motor. You'll then have to slow the idle down after this and your idle MAP will decrease too.

Well spotted re the 6 squirts. This is purely a left over from when I was working out the opening time of my new injectors on the dyno, (mine runs identically on both 2 or 6 squirts so I know the opening time delay is accurate). Basically I altered the opening time in 0.1ms increments and switched back and forward between 2 & 6 squirts until the mixture was the same. It's really not that important, so if yours runs best on 2, then use 2.

My idle AFR is rich around 13.5 or so, but that's with non stock cams, nearer stoic might be better with the factory cams.

Steve

Murray · Post by **Murray** » Wed Mar 08, 2006 3:20 am

Steve I guess I'm being to conservative with my ignition advance.My understanding of Greg's procedure led me to believe that "F" mark which is 2 deg.btdc (factory static) + 6 would give the best results.I'll gladly crank it up if you say it will produce better idle o2 etc.Are you using premium (higher octane fuel) @ 16deg? (I have "S" cams which I guess are slightly different from stock)

Injector opening time is another mystery issue.The Alfa spec.for the low z Bosch injectors is 2 - 10ms.(I assume that the range is largely dependant on the voltage at the inj.) I currently have mine set at 1.0ms per the MS manual but I guess I'll have to tackle that issue at some point.

Steve R · Post by **Steve R** » Wed Mar 08, 2006 8:04 am

Leave the injector opening time at 1.0m, that'll be close enough!

Hmmm re ignition timing, I vaguely recal reading elsewhere on this site that there were various different pulley markings from the factory.... mine has markings at 0, 9 & 32 degrees BTDC (stock euro 3.0 75 pulley) & 1mm of pulley circumference = 1 degree.

Mine idles smoothest at 16, but goes to 9 at WOT at 1000rpm, 12@1200, 20@1500, etc. This is on normal uk 95 RON fuel, & the car runs the same on 97RON.

It's entirely possible that yours is perfectly OK as is using the factory dizzy stuff.

If you ever go full spark control you have more options, for instance if you look at my spark table for 1000rpm and 30MAP it's on a "reverse slope" such that if the idle drops, more advance is added to recover, & if the engine idles faster there's less advance to slow it down. Basically I've got excellent idle speed stabilisation via spark control, without bothering with a different IAC device or relying on the bosch aav being wholly accurate.

Any other opinions from the gang re what advance at idle? As my spark set up isn't directly relevant for Murray's circumstance.

S

Murray · Post by **Murray** » Wed Mar 08, 2006 8:37 am

Steve so your car has vacuum retard as described on Greg's site.Mine has vac.advance.I bumped the timing up to 10 deg.advanced.Lowest MAP is 39 @950 rpm.My VE is at 49 to achieve this,any lower and the MAP starts to increase so I guess that's my bottom end.

Steve R · Post by **Steve R** » Thu Mar 09, 2006 3:00 am

Mine definitely had vac advance as stock, but I think the 3.0 pulley has diff markings and settings to the 2.5 pulley, maybe euro spec cars were different too?

Sounds like the idle is stable, so time to play with the rest now...... Once the weather allows ...

zambon · Post by **zambon** » Thu Mar 09, 2006 11:15 pm

Murray,
I dont know that I have a short, but I am getting incorrect voltage numbers at the processor. Lance on the MS board said he thinks it is a short and I am hopeing that it is due to the fact that the bottom of my board is filthy with flux and rosen

I am THAT guy asking for help when I have not even cleaned my board yet

Oh well, I hope to look into it in the next few days so I can get back to struggling to figure out the computer interface.
I would also like to know your suggestion for how to handle the ignition situation. I am ignorant on ignition issues in general, so I am a little intimidated by this part of the project.
James

Murray · Post by **Murray** » Fri Mar 10, 2006 2:46 am

James yes definitely start with a thorough cleaning, either board cleaner or acetone and a toothbrush. It doesn't take much to create a current path on these things.
I elected to get started with fuel only, based on some very wise advice from others on this board, man I'm glad I did, there are so many parameters and variables to deal with initially there is no need to add to them by doing ignition simultaneously- unless you actually know what your doing

-I didn't.
Now that I have her starting and running reliably I am almost ready to really start learning about ignition curves etc. First I have to wait for Mother Nature to wash away the salt on our roads so I can actually tune my fuelling at more than 2k rpms. Steve R's ignition table will be a good starting point but unfortunately he's not using MSII and his distributor uses a VR sensor not a Hall like ours so there are significant differences in the setup. We can learn together and console each other when we blow holes in the top of our pistons

Steve R · Post by **Steve R** » Fri Mar 10, 2006 2:58 am

Hi Zambon,

If you're worried about the ignition, just stick with the factory Alfa stuff for the time being as it works anyway and trigger the MS from the ignition -ve terminal as per basic MS instructions.

Murray is spot on, the learning curve is far more comfortable if you save ignition control for a phase 2 project.

Re board shorts, giving it a damn good scrub with board cleaner fluid and a toothbrush is the best starting point..... best done outdoors though as the acetone fumes are rather strong!! Most likely it's a bit of excess solder somewhere, which is easly fixed once you find it.

regards
S

Murray · Post by **Murray** » Fri Mar 10, 2006 3:24 am

Steve the acetone fumes are what make this whole project fun