Change Dwell Settings on Furniss Continuous Motion

I am looking to fine tune my dwell settings for my ford "4.6 liter". I am running with ford cops that would be found on the late 90's mark viiis. I am assuming they are similar to the cops that ford still uses. I am driving the coils with 2 bosch 211 4 channel coil drivers. I am not sure at this point what my optimum dwell is at this point but I would like to start by understanding my options in tuner studio. I read through the ms2 documentation on coil dwell. The example given in the ms2 documentation is for a v8 with a single coil. In this example, at 600 rpm there is an ignition event every 25 milliseconds and at 6000 rpm there is an event every 2.5 milliseconds. This all makes sense to me. In my case since I have 8 coils and am not operating in any wasted spark mode, at 6000 rpm my coils have a 20 millisecond cycle time to do dwell and spark. Documentation indicates that a typical dwell time would be between 2 and 4 milliseconds. The way I understand the operation of the coil drivers is they are either in dwell mode or spark mode, meaning there is no 3rd option for "doing nothing". So my thought is that if I have 3 ms of dwell then I have 17 ms of "spark" time. Please correct me if my understanding of any of this is wrong. Here comes the questions.

In tuner studio there is an box to set "maximum dwell" and another for "maximum spark" currently, in my tune, my max dwell is at 3.0 ms and my max spark is a 1.0 ms. These obviously do not add up to the 20ms that I have to work with at 6000 rpm and I have even more time at lower rpms. So what is tunerstudio doing here. Is it possibly just leaving the spark time longer to fill the gap or is it overdwelling the coils or what? I am currently set at "standard dwell" option. Is there any benefit to the other "dwell type" options? Is there any benefit to using the dwell vs rpm curve? should I set my dwell higher at higher rpm to get a stronger spark? or would the curve actually be set to give longer dwell under low rpm and high load to give a stronder spark?

When using spark hardware latency, is this a constant latency value? seems like it would need a higher latency value at higher rpm?

It seems as though I am getting a little bit of fall off in power in the higher rpm range and I dont think it is due to air flow restrictions, at least not at 5000 or 5500 rpm so I am curious if my spark might be lagging. currently I am using the default spark advance table that came in tunerstudio that I think peaks out at 40 degrees advanced. Should I be advancing even further in the upper rpms? could this be why my power seems like its falling off?

any help is appreciated.

Post by **sparky4u2nv** » Tue Mar 15, 2011 5:25 pm

I have a 98 lincoln 4.6 cop with the stock coils. I'm using the BIB373s in a custom box instead of the Bosch modules that you have but I think the 211 modules use these internally. I set the dwell on the bench using the non-scope technique, increase dwell until the BIPs get hot to the touch. I ended up with 1.2ms. However, this is only on the bench. I am just at the point of starting the engine so I don't have any performance input to give you. I had read that the stock coil dwell would be around 1.7ms. My BIPs were getthing hot at that point but I think they could have handled it with the heat sinks that I have.

Steve

Post by **matthewb** » Thu Mar 17, 2011 6:17 am

Does anyone have at least some explanation for the part regarding the tuner studio settings Nmaximum dwell" and "maximum spark"?

Post by **elaw** » Thu Mar 17, 2011 6:28 am

If you're running COP you can consider those settings as "dwell time" and "don't care" respectively...

As your math indicates, when you're running a single coil, dwell time needs to be reduced as RPM increases because the time available between firings becomes less. So the dwell setting is labeled "max" because depending on RPM it might be less. The "spark duration" setting is the amount of time MS will wait after firing the coil before re-engergizing it again - this also factors into dwell reduction.

With COP, unless you're running at crazy high RPM, the available time between sparks is not an issue. So the "max dwell" number is used all the time and is never reduced.

One other thing to keep in mind is that if you look at dwell in a log or using a gauge in Tunerstudio, the number you see might not be exactly the time set in "max dwell" - that's because it's corrected for battery voltage (dwell gets lower as voltage increases).

Post by **elaw** » Thu Mar 17, 2011 6:33 am

Oh and about spark hardware latency... a constant time delay represents an increasing angular delay as RPM increases. So if you're seeing unexpected timing retard with increasing RPM, plugging in a latency number that's > 0 should correct it. If you're seeing unexpected *advance* with RPM, your spark output polarity is probably set wrong.

Post by **sparky4u2nv** » Thu Mar 17, 2011 7:13 am

Matthew,
I've done quite a bit of searching for the Ford COP dwell setting and there is very little to be found. But, I did find a couple things. I set mine according the the "hot to touch" method explained on the diyautotune web site. The article is on using the Bosch BIP373 coil driver, which I am using. It sounds like the 211 module that you are using might have this component inside. Eiher way, the setting is specific to the coil and has to do with the time it takes to charge. I will check it on a scope when I can borrow one from work.

http://www.diyautotune.com/tech_article ... squirt.htm

I came up with 1.2ms dwell for the stock ford 32V coil using this method. At 1.5ms they would get warm in bench testing but not hot. They change temperature and stabilize very quickly. I ran them well past stabilization at 1.7ms and they were hot but never shut down.

After doing this I found the following link that has the Ford COP dwell setting as 1.5ms.

http://www.msextra.com/forums/viewtopic ... erred+coil

This came from the motec web site. I'm going to run mine at 1.5ms unless I have problems. Thanks to you, I just got my engine running so I should see soon.

Steve

Post by **matthewb** » Thu Mar 17, 2011 7:23 am

Thank you for the info. I am not sure if you looked at that part of my msq but if you did you would have seen that my max dwelll was set to 3ms. So should I just set this to 1.5 unless I have issues? Are you using the "standard dwell" setting?

I had discussed it with my dad, he is an EE, and he decided he would not really be allowed to test this on a scope at work but he is currently looking for a scope for a reasonable price for us to buy for home. If we can get a scope we should be able to pin point the appropriate dwell but if you beat me to it then that is even better.

Thanks

Post by **sparky4u2nv** » Thu Mar 17, 2011 9:33 am

Yes standard dwell. I saw in your post that you had it set to 3ms and I think 6ms for crank. I had replyed but somehow my reply didn't post so I reposted today.

I would think that either your modules or your coils or both would get pretty hot at that setting. I would reduce it to 1.5ms and maybe 3ms for crank.

I'll let you know if I get to put a scope on it and measure. It's on a long list of tasks to get to before my car is drivable.

Post by **Eaallred** » Thu Mar 17, 2011 4:02 pm

I'm running Accel coils for the 3-valve 4.6 on my VW bug.

I built a box for my BIP373's that houses them, built little heat sinks for them, the box itself has a small cooling fan drawing air through it to keep them cool.

Dwell on mine is 6 cranking, 3 running. The spark jumps a larger air-gap than my old 6 series CDI could so im happy.

I've driven it 20 miles at at time so far with no coil overheating or shutdowns so far.

Post by **matthewb** » Thu Mar 17, 2011 7:02 pm

I set my dwell down to 1.5 and 3 tonight and took the car for a short drive. It didn't have any issues in that short trip but I didn't do any bogging it down either. I also didn't get to play around with going any lower. So I may get to play around with it in the next few days. Thank you for the suggestions.

It was mentioned that max spark time is irrelivant, should I just leave it at 1 as it was or should I put it at 0 or can it be left blank. I guess it may not matter much. It seemed to me like logically it should have been minimum spark time though.

Post by **PanchoMr2** » Wed Nov 02, 2011 6:19 am

sorry to bring this up but i have a question about the Ford COP i have now. i have 4 garnetelli COP for Ford 4V, would like to know as possible is the same as yours which is the positive and ground?

Thanks

Change Dwell Settings on Furniss Continuous Motion

Dwell settings with Ford cops

Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

Re: Dwell settings with Ford cops

0 Response to "Change Dwell Settings on Furniss Continuous Motion"

Post a Comment

Iklan Atas Artikel

Iklan Tengah Artikel 1

Iklan Tengah Artikel 2

Iklan Bawah Artikel