Its Alive!

[jsvxstyle]

Originally Posted by mbtoloczko

Hey cd, are you using the factory crank angle sensor, or did you adapt a Electromotive crank angle sensor?

alright, my standalone when i ran my subie, was an ecu 882c. from pantera. my refrence wheel was bolted to the back of the crankshaft boss fot he timing belt in front of the engine, it is the encoding wheel wheel, i wish i had a camera, to sow you guys. i had a crank triger ecxactly where the cranksfat sesnor was, the encoding wheel is 3.5 inches long with 56 teeth,, it took me 2 days to wire the system, but when lance said just start it. it will run very good, but still you need to tune the system. and yes it ran great. i tuned the system made the adjustment with the redline software with the engine running, but when lan came out with the s/c i took out my standalone.

[jsvxstyle]

dude. soo sorry about my speeling, lol

[cdigerlando]

Originally Posted by longassname

I think your challenge will be finding someone who is both very familiar with your engine management system and has acess to an awd dyno.

You hit the nail on the head here. They exist, but in California. I was thinking of calling Maestro Subaru to see if any of their techs have tuned with electromotive. But even then it is usually an impreza, not an SVX.

What minimum injector on-time do you use? What time on gamma (TOG) do you use? What injector offset do you use? I don't know if these are terms used in the JECS software you are using or not. TOG is the time allowed for a full pulse of the fuel injector. Injector offset time changes when the injector opens and is adjusted at idle. Minimum injector on-time is the minimum time that an injector is designed to properly deliver fuel. This is probably more like 1.3 for our nismo injectors, which is something I'm going to play with.

I am using TOG = 6.1 ms, IOT = 0.75 ms, and a minimum injector on-time of 0.9 ms. What are you using?

[cdigerlando]

Originally Posted by longassname

As far as the acuracy of the crank angle sensor I don't think it can match the timing of the injector pulses without a cam angle sensor and knowledge of the cam profile. It's the combination of the two sensors which enables the ecu to acurately identify both which cyllinder is firing and when the valves will open. With only a crank angle sensor you'd have to divide the 360 degrees up for identifying the cyllinder then divide it up again to identify when the valves will open. The wheel for your crank angle sensor would have to be 10 feet around to come close to the resolution of the combination of a crank and cam sensor.

The cam profile doesn't change with RPM, and if it did, that is also an idenifiable point that TEC II can deal with.

A cam sensor needs twice the teeth of a crank sensor since it turns every other revolution to have the same resolution as a sensor on a crank. I don't know how many teeth are on the stock cam and crank, but take the crank and add cam/2. That would be the resolution. Mine is 60 or 1 every 6 degrees. Any adjustments in timing due to early valve opening are handled with timing adjustments, just like your JECS.

I'm not an expert tuner. You would really be better discussing the pros and cons of the engine management in an engine management forum with folks who know a whole lot more about it than me. There are also a lot of superior and easier to use packages than the Tec II. Remember I got this some time ago. I have heard a lot of good thinks about Autotronic.

Is the JECS user tunable? I know you can tune it, but is that available to folks you are selling this to in a user tunable form?

[longassname]

No those aren't standard terms. Those are particular to your electromotive system. You'll have to read your documentation and figure out more accurately what they actually mean. Standard injector information is it's flow rate and latency. A JECS system also works with the effect of battery voltage on the latency. To get this information you need to send your injectors to rc engineering to get them flow tested.

If 6.1ms is the maximum pulsewidth you have the ecu set to allow that sounds a little low. That's enough for stock manifold pressure but I see more than that with the 740cc injectors I run. If that is in fact what this setting is then bump it up to 9.

In standard terminology latency and minimum pulsewidth are the same thing. So I'm guessing what you are calling minimum pulsewidth is set to maintain idle. Factory idle is 3.07ms so yours should be 550/275 * 3.07 = 1.53ms

.75ms is in the ballpark for the latency. Again to get the real value you need to get the injectors flow tested by rc engineering at the fuel pressure you are running.

As far as maestro being able to tune that system I would say no. Sounds like you are driving to cali.

Originally Posted by cdigerlando

You hit the nail on the head here. They exist, but in California. I was thinking of calling Maestro Subaru to see if any of their techs have tuned with electromotive. But even then it is usually an impreza, not an SVX.

What minimum injector on-time do you use? What time on gamma (TOG) do you use? What injector offset do you use? I don't know if these are terms used in the JECS software you are using or not. TOG is the time allowed for a full pulse of the fuel injector. Injector offset time changes when the injector opens and is adjusted at idle. Minimum injector on-time is the minimum time that an injector is designed to properly deliver fuel. This is probably more like 1.3 for our nismo injectors, which is something I'm going to play with.

I am using TOG = 6.1 ms, IOT = 0.75 ms, and a minimum injector on-time of 0.9 ms. What are you using?

[longassname]

It's not a matter of the cam profile changing at rpm. It's just a matter of knowing where in the rotation the valves for each cyllinder open.

No you aren't quite getting it with the crank and cam sensors. That's not the right math. It doesn't sound like your system tries to time when fuel is injected just how much. No biggie. It won't perform as well but like I said before you work with what you've got. There are plenty of fuel injection systems that work the same as yours. You should just keep it in mind while tuning your system in order to work with it instead of against it. Fuel will displace aircharge trying to flow through the valves while they are open so you will see higher manifold pressures for the amount of aircharge actually in the cyllinders. The fuel won't be vaporized as well so idle may not be as smooth. The valves won't be cooled as well so you won't be able to run as high of a cyllinder pressure without running into knock.

Originally Posted by cdigerlando

The cam profile doesn't change with RPM, and if it did, that is also an idenifiable point that TEC II can deal with.

A cam sensor needs twice the teeth of a crank sensor since it turns every other revolution to have the same resolution as a sensor on a crank. I don't know how many teeth are on the stock cam and crank, but take the crank and add cam/2. That would be the resolution. Mine is 60 or 1 every 6 degrees. Any adjustments in timing due to early valve opening are handled with timing adjustments, just like your JECS.

I'm not an expert tuner. You would really be better discussing the pros and cons of the engine management in an engine management forum with folks who know a whole lot more about it than me. There are also a lot of superior and easier to use packages than the Tec II. Remember I got this some time ago. I have heard a lot of good thinks about Autotronic.

Is the JECS user tunable? I know you can tune it, but is that available to folks you are selling this to in a user tunable form?

[cdigerlando]

Originally Posted by longassname

It's not a matter of the cam profile changing at rpm. It's just a matter of knowing where in the rotation the valves for each cyllinder open.

No you aren't quite getting it with the crank and cam sensors. That's not the right math. It doesn't sound like your system tries to time when fuel is injected just how much. No biggie. It won't perform as well but like I said before you work with what you've got. There are plenty of fuel injection systems that work the same as yours. You should just keep it in mind while tuning your system in order to work with it instead of against it. Fuel will displace aircharge trying to flow through the valves while they are open so you will see higher manifold pressures for the amount of aircharge actually in the cyllinders. The fuel won't be vaporized as well so idle may not be as smooth. The valves won't be cooled as well so you won't be able to run as high of a cyllinder pressure without running into knock.

Idle seems just fine. Just rich. The car runs generally the way it did before I added the Tec, which gives me hope. My big problem is I don't have a wideband right now Blake is comming by on Sunday so we will play some more with the fuel and injector settings. 1.53 is a pretty high a latency. But not too much different from what I would expect from high impedance injectors. I'm not quite sure how you did your calculation though.

As far as arguing about the cam position, I'll see how tuning goes and let you know what I come up with for results. And no I won't be going to California.

[longassname]

you didn't read very carefully.

i said that .75ms sounds about right for latency and explained about actually measuring it.

I said 1.53ms is about right for a min pulse width

you might want to take the time and effort to read and understand what I'm saying. It's not speculation. I'm giving you the information you need to get going in the right direction on your project.

[cdigerlando]

Originally Posted by longassname

you didn't read very carefully.

i said that .75ms sounds about right for latency and explained about actually measuring it.

I said 1.53ms is about right for a min pulse width

you might want to take the time and effort to read and understand what I'm saying. It's not speculation. I'm giving you the information you need to get going in the right direction on your project.

Don't get upset, I do read what you wrote, but I probably need to explain the terms I wrote about better, because your idle min had me confused. I don't physically change the idle pulsewidth. In Tec II it is a function of the fuel curve drawn through the IOT point and the maximum pulsewidth that I pick. I can also pick a min pulsewidth, but it doesnt help my idle, unless I'm bumping up against it. To be safe and conservative I used a pulsewidth based on a max RPM of 7000. This gives me a max TOG pulsewidth at full open of 7.37, using a 1.2 ms recovery time. That is 60000 (ms/min)/7000 rev/min - 1.2 ms. That is basically where I started. I could probably back into 9 if I dropped the rpm and the recovery time a bit. Actually I have run as high as 10, but again too rich at idle and moved down slowly from there. I would definitely like to run more TOG for future tuning though. So it sounds like my minimum pulsewidth should be set at .75, which is normally too low for high impedance injectors (.9-1.3 ms). Are you running low impedance injectors? I thought you were running nismos. I'll give it a try with my nismos. That may help.

[longassname]

I don't think it's that you need to explain the terms you are using better. I think you need to stop thinking about your terms and start thinking about what you are trying to do. If something I say confuses you that's a good hint that that's an area you need to look into more closely in order to expand your understanding of the #s you are tinkering with.

Injector latency is a min pulsewidth by it's nature but it doesn't have to be the only min pulsewidth and it sounds like in your case it is not. An engine management system adds the injector latency to any pulsewidth it calculates thus making the latency the min pulse width that it will ever calculate. Thus it is sometimes called a min pulse width. Engine management systems often have another floor set to maintain idle in case ocassion arizes that the load reading goes below what would maintain engine operation. We normally speek of this as a min air flow or min load not min pulsewidth; none the less, the unit for load is often ms of injector duty. Whatever you call it doesn't matter. If you are setting a floor to maintain engine operation it would be right around the 3.07ms that maintins idle on the factory svx multiplied by the ratio of your injectors to the factory injectors 275/550 so 1.53ms.

It would be best if you flow tested your injectors to find out the correct latency. It's a lot easier to do enter the right # and if it doesn't run as you expect know that something is wrong that to try to determine your #'s by trial and error. But if you set your floor to maintain idle like I said and your latency is correct you will idle at 14.7 to 1. If you idle rich your latency is too large. If you idle lean your latency is too small. The .75ms you said you are running is in the ballpark for those injectors. The actual latency may be a little higher but it should still be less than 1ms. Starting at .75 and adjusting to idle at 14.7 should work fine.

[dieingSVX]

i don't know what to say. i do know the problem we had before was an inconsistant afr at idle. sometimes it would idle 12.5-13.0afr @idle and with the same settings you crank it back up it would idle 16+afr. there is something else in the system that we have evidently missed that is causing this. i don't think it is to hard to guess the latency of a set of injectors. you enter a number and work your way up or down from there. i meant to sit down and do a basemap on my computer with some numbers i picked up, but this has been a busy week and will be a busy weekend. i will only be over to drop off some of my stuff to cdigerlando and chat for a few minutes.

LAN btw if you think someone doesn't understand what you say try explaining it in a non dick way. i don't think there are to many people on this site that have as many resources as you. some of us are trying to work with what we have.

[longassname]

If my responses seem "d*ck" I appologize. It was obvious from his posts that he was set in his way of thought enough that he was discarding what didn't fit into it off hand instead of figuring out where his line of thought needs changing. I'm being very blunt not because I like to be a "d*ck" but to try to help him be successful in quick order. I'd rather come off harsh and have him succeed than come off nice and leave him to flail.

[cdigerlando]

Well, its alive might not have been the best subject for the post. Its wounded might have been more accurate. I had some overheating when driving slowly, which I thought might have been due to a thermostat sticking, since it would come and go. Got an exhaust gas coolant tester and found that I have a blown head gasket. Not suprising since the car has been sitting for so long.

I think I'm going to go ahead and have the engine rebuilt at this point. I feel confident that the engine management and fuel injection will work, since I have been able to get the thing idling steady, just fluctuates a lot.

I will be looking into lowering the compression to 8.5:1 with new pistons, and possibly strenghthening the valve train, rods, and perhaps increasing the valve lift. Any suggestions at this point would be appreciated.

Thanks

Chuck D.

[cdigerlando]

BTW. off the subject. Blake stopped by yesterday to loan me his wideband. I got a chance to ride in his cobra. That thing was very fast. Good thing he didn't run all his boost, I might have left a stinky in his car.

[dieingSVX]

i can take you for a ride with full boost just remember that's the slower out of the two mustangs...

anyways sorry to hear about your car. that does suck pretty bad. just give me a shout and i'll come over to help you. we can have your engine and tranny on the ground in a few hours.