Megasquirt 2 Help / General tuning

[Waigan]

Hey guys,

We need some help tuning our megasquirt 2. We use a honda cbr rr. We are having troubles with getting it started. We are still a fairly new team and still have trouble tuning. I was wondering if anyone would be able to share some engine maps with us.

We have been trying to get our engine started for the last week and have really gotten no where. We got it so it sounds like the engine is so close to starting but it won't keep itself running. We have reached somewhere around 1000 rpm's. This leads me to think that we have the crank settings decent but we cant get the ASE (after start enrichment) correct.

What are your guy's fuel and ignition maps or is there a way to convert a stock map to agree with our SAE inlet restrictions?

[Waigan]

Hey guys,

We need some help tuning our megasquirt 2. We use a honda cbr rr. We are having troubles with getting it started. We are still a fairly new team and still have trouble tuning. I was wondering if anyone would be able to share some engine maps with us.

We have been trying to get our engine started for the last week and have really gotten no where. We got it so it sounds like the engine is so close to starting but it won't keep itself running. We have reached somewhere around 1000 rpm's. This leads me to think that we have the crank settings decent but we cant get the ASE (after start enrichment) correct.

What are your guy's fuel and ignition maps or is there a way to convert a stock map to agree with our SAE inlet restrictions?

[Mikey Antonakakis]

Check your timing (with a timing light). You should be running somewhere around 10 degrees advance at idle, maybe more. We had an offset problem last year that I never properly fixed, but the engine ran a whole lot better when I made corrections for the 25 degree offset, wherever it was coming from.

Make sure your injectors are set up properly (Settings/Injector Control, click Required Fuel). This will give MS a pulse width that corresponds to 100% VE and stoich AFR (called Required Fuel). Then set your idle VE to around 60%. If you're anything like us, your MAP reading should be pretty high at idle (80kPa?). Do you have an O2 sensor? If not, get one, it is worth the money, especially if you have no tuning experience. If you can keep the engine running long enough to warm up, set your fuel map values for the idle portion of the map when it is warm and there are no enrichments. Then, start fiddling with afterstart and warmup enrichments.

Rules of thumb:
if you hear popping in the intake, ADD FUEL
if there are flames shooting out of your exhaust, add timing in the part-throttle region or take out some fuel, or a bit of both.

Most importantly, get an O2 sensor working! A good setup should be around $400 and is invaluable.


Also, read ALL of megamanual. There is a TON of GREAT info in there that should clarify most questions you have about tuning. Particularly of interest should be "Configuring Megaquirt II" and "Tuning Megasquirt II"

www.megamanual.com (http://www.megamanual.com)

[Grant Mahler]

ASE only matter once you pass the crank threshold into running...This is a value (RPM) you set.

I strongly doubt its the ASE that is the issue at the moment.

Pull a plug, ground it against the block, crank. If you get spark, it may not be sufficiently strong, or at the correct time. If not, check wiring, settings, etc. Alternatively, try spraying a little carb cleaner in the intake. If she pops and runs for a couple seconds, you have a fueling problem. If it doesn't pop, you have either a spark problem or your intake valves never open (I know someone who forgot to attach their timing chain).

Pull an injector, hold it over a cup. If you get fuel, it may be too much, or too little, or old.

There is not a way to convert a stock map to agree with your SAE inlet restrictions.

[Tom W]

But the restrictor won't be doing much at 1000rpm or 2000 for that matter...

[Waigan]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Grant Mahler:
ASE only matter once you pass the crank threshold into running...This is a value (RPM) you set.

I strongly doubt its the ASE that is the issue at the moment.

Pull a plug, ground it against the block, crank. If you get spark, it may not be sufficiently strong, or at the correct time. If not, check wiring, settings, etc. Alternatively, try spraying a little carb cleaner in the intake. If she pops and runs for a couple seconds, you have a fueling problem. If it doesn't pop, you have either a spark problem or your intake valves never open (I know someone who forgot to attach their timing chain).

Pull an injector, hold it over a cup. If you get fuel, it may be too much, or too little, or old.

There is not a way to convert a stock map to agree with your SAE inlet restrictions. </div></BLOCKQUOTE>

Well we know that the engine is getting fuel and spark. It sounds like it so close to running. Our cranking threshold is 350 rpm's and we are able to get the engine to "run" well over that (near 1000 rpm's). So this is why I believe it the ASE.

I'll check to see if we have weak spark today. What do you guys have your cranking advance set to?

Also I forgot to mention we are running e-85 and it is fresh fuel...just picked it up last week.

Thanks again

[Brian S]

You might try hooking up a larger battery or charger. We have found that if the car battery isnt completely topped off it is really hard to start, but as soon as we hook up a fully charged one it takes right off. We're running an f4i on MS2 btw.

[Waigan]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brian S:
You might try hooking up a larger battery or charger. We have found that if the car battery isnt completely topped off it is really hard to start, but as soon as we hook up a fully charged one it takes right off. We're running an f4i on MS2 btw. </div></BLOCKQUOTE>

Yeah we have a charger on the battery at all times. Most of the time it is topped off but we are still having troubles.

What do you have starting settings set to (cranking advance, timing, fuel, ase % ase taper). You don't need to give us your maps if you don't want but if you can give us pointers or hints. But maps would be greatly appreciated! http://fsae.com/groupee_common/emoticons/icon_smile.gif

Thanks for helping

[Mikey Antonakakis]

Pull your plugs. Clean or replace them if they look fouled. Can't tell you how many times we weren't getting good spark because of the plugs. Check your ignition dwell. Should be 2-4ms. I'm not sure you'll get maps out of anyone... personally I don't have one on the computer I'm using right now, but I also think you should be able to figure this out yourself, and will learn a hell of a lot more that way. You need to write your own map anyway. Go back and read what I said, I even gave you some values for idle VE. 60-70%. That's the only thing you need to get the engine running.

I second the starter fluid/carb cleaner suggestion.

Also, check your timing with a timing light. I was 100% sure the crank trigger was installed correctly, but as I said somewhere there was a 25 degree retarded offset. That 25 degrees made a HUGE difference in starting and idle.

You have a limited number of variables you can work with. Go down the list and eliminate as many as potential sources of problems as possible. You need some combination of fuel and a reasonably timed spark and the engine will definitely run.

Are you running TPS or MAP based load? If MAP, check for vaccuum leaks.

Here's a list:

Fuel issues:
-Required Fuel value is off-check your injector specs (230cc/min for F4i injectors)
-Make sure that in the reqfuel calculator and injector characteristics that you have the correct number of squirts, as well as displacement and number of cylinders-refer to megamanual if confused, it's the closest to an EFI tuning bible I've come across
-make sure you have fuel pressure
-watch the injector pulse width value on the dashboard as you attempt to start- it should be somewhere around 3ms, closer to 2ms at idle when you're warm, assuming the injectors are similar to an F4i. Somewhere around the 2-4ms range is all I've ever seen with the F4i.
-values in your fuel map are wrong-they should be somewhere around 50-70% at idle (70-100kPa, 1000-2000rpm)
-if you have no luck adjusting fuel maps to get it started, turn the ASE and WE down a bit, that at least somewhat worked for me before i fixed the timing issue
-play with the throttle as you try to start it. It makes it a million times easier to start if you just give it a little throttle

Ignition:
-check that you have spark-hold plug against block
-if you have spark, check your plugs. if they look dirty, clean them or replace them
-check all of your connections. Firing order is 1-2-4-3. Check this for ignition and fuel
-check your timing with a timing light. if it doesn't match the ignition map, fix it
-check your cranking advance-there is a specific setting for this-make sure it is a reasonable value
-if you don't have a timing light, start retarding timing at idle. If that helps, keep going until you get it to idle. But the easier way is to buy or borrow a timing light. If you have around 10 degrees advance at idle, and can't get it to run, you either don't have a strong enough spark, or a fuel issue (our engine idled at 15 degrees retard until I found the offset issue, then it idled much better). If you have good spark, add or subtract fuel until it runs. It's pretty simple. But I can't stress the importance of checking your timing and having a wideband O2 sensor. Your life will be soooo much easier and tuning the engine will be so much more fun.


As far as enrichments are concerned, you really shouldn't have to worry about those. Read the pulse width on your dashboard. If the RR injectors are like the F4i injectors, you should have maybe 3ms pulse width when cranking. Don't forget to flood clear often. Make adjustments of whatever value you want (fuel map, ase, we, whatever) until you can get the thing running long enough to warm up. Once it's warm, get the idle portion of the map dialed in. Then start trying to rev the engine, and get more of the fuel map filled in. Once you have the idle portion of the map filled in though, you shouldn't really have to change it. If you can't get it to restart, change your cranking settings. If it starts, then dies within a few seconds, change ASE. If it runs for more than a few seconds, then dies, or runs poorly, change your warmup enrichment. If I understand it properly, WE and ASE are both active when you first cold start the engine. There are red boxes at the bottom of your dashboard that tell you which enrichments are active, and even if you're cranking or not. That should also help you diagnose which of the enrichments/settings is causing your issue. Have fun!

[Mikey Antonakakis]

Also, keep in mind that the pulse widths and advance values I gave you were for gasoline. I know nothing about how E85 affects things.

[Waigan]

Hey Mikey,

I didn't even notice your first post. Thanks for all your help. I'll keep everything in mind for later tonight when im back in the lab.
I'll definitely check timing because our tables don't make sense.

By the way, I think your team helped us out a lot in 2007. Thanks for being so helpful. We owe you http://fsae.com/groupee_common/emoticons/icon_smile.gif

[abinley]

Turn your cranking rpm up as high as it goes or you will start reading from the maps during cranking. Make sure your warm up enrichments aren't at 0%. 100% means no enrichment, so I would start by entering 100% for each temp to begin with.

[Grant Mahler]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by abinley:
Turn your cranking rpm up as high as it goes or you will start reading from the maps during cranking. Make sure your warm up enrichments aren't at 0%. 100% means no enrichment, so I would start by entering 100% for each temp to begin with. </div></BLOCKQUOTE>

I disagree with everything you said.

Set the crank threshold to a reasonable number. A reasonable number is a couple hundred RPM above what your starter motor is able to crank with the battery fully charged. A reasonable number is also a couple hundred RPM below what the stock engine idled at.

For reference, on a Suzuki LTR450, the starter will spin it ~480RPM. The stock idle is 1800-2800 (low/hi idle). I set my threshold to 650RPM. I was able to idle the engine ~1900RPM.

The default enrichments should be either left alone (default), or I actually agree with Mikey, turn them down. For ASE they can get very confusing to get right the first time. Its easy to flood an engine while you are setting up your first map.

And turning ASE to 100% will double your fuel table. With absolutely no logic. WTF?

Mikey and Brian both know exactly what they are talking about - both have been around tuning MS for a while. Listen to them.

[Mikey Antonakakis]

I second Grant's crank threshold statement.

MOST IMPORTANTLY

READ MEGAMANUAL

it's great!

[Waigan]

OK....lol it was timing....it started right up after we fixed the timing problem.

Thanks for everyone's help.

[Mikey Antonakakis]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Waigan:
OK....lol it was timing....it started right up after we fixed the timing problem.

Thanks for everyone's help. </div></BLOCKQUOTE>
I had a feeling http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Grant Mahler]

Does MS2/E deal with cranking timing better than a year ago?

We had a hell of a time getting our cranking timing values to work out. Despite setting a cranking value, the MS2/E wouldn't actually use that value. It always just went to 0 cranking timing.

We ended up with a known offset (10*) so that the engine would start. Made the map look a little funny though, with all the values off by 10*.

[Mikey Antonakakis]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Grant Mahler:
Does MS2/E deal with cranking timing better than a year ago?

We had a hell of a time getting our cranking timing values to work out. Despite setting a cranking value, the MS2/E wouldn't actually use that value. It always just went to 0 cranking timing.

We ended up with a known offset (10*) so that the engine would start. Made the map look a little funny though, with all the values off by 10*. </div></BLOCKQUOTE>

Honestly, I'm not sure what the cranking timing was. I know it was set to 10 degress at some point. It starts right up though, especially if you blip the throttle while you crank it. It really was a last minute scramble to get our engine tuned last year. I do know that I ended up having to add about 25 degrees to the whole map though because for some reason the trigger offset value would never save. I'll get that figured out this year though, we should have our engine dyno running in a couple months. I'm so excited, I'll actually get to validate intake and exhaust design!

[kracer]

Hello all,

I've got a single-cylinder 450 retrofitted to EFI with a Megasquirt ECU
When setting up a Megasquirt engine for start-up, the cranking spark advance can be adjusted quite freely in the Cranking & Idle tab of the Tuner Studio.

My team actually used this in combination with a carb set-up to tune ignition and idle the motor.

Pulse width doesn't seem to have as much freedom.
When setting up the cranking pulse width, it only seems to be based off the Idling PW.
Is there a way to set Cranking PW separate from Idling PW with the same freedom as spark timing?


My team's got:
MS3 Board,
MS2 Processor,
MS2-Extra Code....

[Mumpitz]

Cranking advance is set in the Ignition Settings / Ignition Options tab. Cranking PW is set by the fuel VE Table and then multiplied by scalars like Cranking Pulse which is also coolant temp dependent. This is a good thing, while a single value for cranking timing may be fine from 20F to 120F your fueling definitely isn't. It is a trial and error process.

[kracer]

Wonderful Mumpitz, found those.
How about injection timing?
To accommodate altered cam timing...

Injector characteristics tab doesn't include options for injection timing/phasing.

I figure this is one of my biggest hang-ups, cuz with a carb, the fuel flies into the cylinder on its own when the valve opens.

[Mumpitz]

Correction, Cranking Pulse is a percentage of "Required Fuel" (100% VE), pretty easy to back calculate the ms or just watch your PW gauge and +/- from there.
Injector timing is way down on the list of critical settings in my opinion unless it is waaaay out. Draw yourself a timeline of events through out the engine cycle, now consider the duration of each event and how it changes with engine speed. This should paint a clear picture of when you should be opening the injector and that will be good enough for a base-line, the dyno should tell you if changing that is worth while.

[kracer]

Mumpitz, the timeline sounds like a good strategy, I will give it a shot once the motor is idling and the tuning can begin.

I'm interested in finding where the Injector Timing setting is located in TunerStudio.

I have fuel accumulating in the intake port that I believe is causing sputtering through the throttle body(which would probably damage the complete intake system later on). I've leaned out the cranking PW to 70% of "Required Fuel", still seeing the sputtering.

Not sure if this is the root of why the EFI set-up is not idling, but it seems logical given the leftover fuel in the intake port.