Ignition timing for turbo or supercharged renesis - post your maps
04-25-2009, 05:17 PM
#30
heh - i've hit redline with my MIL in the car - I think she just thought wqe were going into hyperspace for a moment - no biggie .
SO ............... are you saying the whole dwell table is designed to give around 3ms of dwell across the board ?
SO ............... are you saying the whole dwell table is designed to give around 3ms of dwell across the board ?
04-25-2009, 08:30 PM
#31
Hmmmmmm.........
Join Date: Mar 2005
Location: Melbourne, Australia
Posts: 3,564
Likes: 0
Received 6 Likes
on
4 Posts
Kane are you saying that the dwell time in the map INCLUDES some PCM "reaction" time ie a dwell setting of 1200 is likely to be an actual coil dwell period of say 900ms plus 300ms of PCM "reaction" time?
Cheers
Andrew
Cheers
Andrew
04-25-2009, 09:07 PM
#32
The short answer is that I don't know - what I do know is that the Yukon's need 5 ms - and the factory dwell is set up at 3-3.8ms at idle.... so
5/3 = 1.666 round to 150% just cause; increase dwell by 130-170% and the car responded well to the changes.
5/3 = 1.666 round to 150% just cause; increase dwell by 130-170% and the car responded well to the changes.
04-25-2009, 09:38 PM
#33
a.k.a. WhITeRE8
iTrader: (8)
Join Date: Apr 2005
Location: Nor Cal *
Posts: 2,231
Likes: 0
Received 0 Likes
on
0 Posts
nice info in this thread and thanks kane for posting the dwell time for the yukon coils. I just imputed the settings you made and the car runs fine, but will know more by tomorrow when I get to drive it more.
04-25-2009, 10:03 PM
#34
not to distract the tread but here is a testing of the ls2 coils for dwell
ls2coil test
after some more research I found a discussion on a locked forum (perth rotary)
quoting bumpstart from perth rotary.
"
note what happens at 9000 rpm in wastespark with a 3.5 fixed ECU dwell igniter !
in math -
rpm/ 60 ( secs ) = rev per second
9000/ 60 = 150 rev per second
1/ 150 = 0.00667 of a second per rev
= 6.67 ms for every engine revolution between spark events per coil in sequential ignition application"
now the best charge time for a yukon coil is 5 ms and the spark duration is between 1.5 ms and 2 ms.
6.5 to 7 ms total duration. very close to never fully discharging.
ls2coil test
after some more research I found a discussion on a locked forum (perth rotary)
quoting bumpstart from perth rotary.
"
note what happens at 9000 rpm in wastespark with a 3.5 fixed ECU dwell igniter !
in math -
rpm/ 60 ( secs ) = rev per second
9000/ 60 = 150 rev per second
1/ 150 = 0.00667 of a second per rev
= 6.67 ms for every engine revolution between spark events per coil in sequential ignition application"
now the best charge time for a yukon coil is 5 ms and the spark duration is between 1.5 ms and 2 ms.
6.5 to 7 ms total duration. very close to never fully discharging.
Last edited by rotarenvy; 04-26-2009 at 01:03 AM.
04-26-2009, 10:18 AM
#35
Fundamental misunderstanding in how the dwell table works here.
Fundamental misunderstanding in how the coils fire.
Fundamental misunderstanding in what the Yukon coils "need" for dwell time.
There is so much FUBAR info in this thread I can't even look at it without my head hurting, hence my post here.
Try actually scoping the output before you make such drastic assumptions about how all of this works.
Also, do the math on what the dwell "requirements" are. Don't forget to include what the spark voltage requirement is to jump the gap under operating conditions. You will see why there is no need to concern yourself with dwell settings in an NA application and why it only matters at 300g/sec + from 4200 RPM until 6800 RPM.
Fundamental misunderstanding in how the coils fire.
Fundamental misunderstanding in what the Yukon coils "need" for dwell time.
There is so much FUBAR info in this thread I can't even look at it without my head hurting, hence my post here.
Try actually scoping the output before you make such drastic assumptions about how all of this works.
Also, do the math on what the dwell "requirements" are. Don't forget to include what the spark voltage requirement is to jump the gap under operating conditions. You will see why there is no need to concern yourself with dwell settings in an NA application and why it only matters at 300g/sec + from 4200 RPM until 6800 RPM.
04-26-2009, 02:16 PM
#36
Fundamental misunderstanding in how the dwell table works here.
Fundamental misunderstanding in how the coils fire.
Fundamental misunderstanding in what the Yukon coils "need" for dwell time.
There is so much FUBAR info in this thread I can't even look at it without my head hurting, hence my post here.
Try actually scoping the output before you make such drastic assumptions about how all of this works.
Also, do the math on what the dwell "requirements" are. Don't forget to include what the spark voltage requirement is to jump the gap under operating conditions. You will see why there is no need to concern yourself with dwell settings in an NA application and why it only matters at 300g/sec + from 4200 RPM until 6800 RPM.
Fundamental misunderstanding in how the coils fire.
Fundamental misunderstanding in what the Yukon coils "need" for dwell time.
There is so much FUBAR info in this thread I can't even look at it without my head hurting, hence my post here.
Try actually scoping the output before you make such drastic assumptions about how all of this works.
Also, do the math on what the dwell "requirements" are. Don't forget to include what the spark voltage requirement is to jump the gap under operating conditions. You will see why there is no need to concern yourself with dwell settings in an NA application and why it only matters at 300g/sec + from 4200 RPM until 6800 RPM.
04-26-2009, 02:39 PM
#37
A whole bunch of crap has been pushed out onto this board about how this thing works and when it doesn't.
Much of this is based on a fundamental misunderstanding of what the BHR kit is supposed to do and how.
As designed (and for the application for which it was designed), it works exactly as advertised.
If you lack the proper tools to modify the system and the tuning to suit a purpose beyond that which the system was designed to address, than you are **** out of luck.
04-26-2009, 02:48 PM
#39
Look -
A whole bunch of crap has been pushed out onto this board about how this thing works and when it doesn't.
Much of this is based on a fundamental misunderstanding of what the BHR kit is supposed to do and how.
As designed (and for the application for which it was designed), it works exactly as advertised.
If you lack the proper tools to modify the system and the tuning to suit a purpose beyond that which the system was designed to address, than you are **** out of luck.
A whole bunch of crap has been pushed out onto this board about how this thing works and when it doesn't.
Much of this is based on a fundamental misunderstanding of what the BHR kit is supposed to do and how.
As designed (and for the application for which it was designed), it works exactly as advertised.
If you lack the proper tools to modify the system and the tuning to suit a purpose beyond that which the system was designed to address, than you are **** out of luck.
04-26-2009, 03:33 PM
#43
That is what the FSM tells you to do - set the DIV to 10 MS and height DIV to 2 volts - then with the car at idle look for the PCM pulse to the coil and it should be at or about 4-5 ms for the whole charge and discharge.
This plus Jeff's earlier posts about ignition dwell is what led me to my widly inaccurate theory I guess...
The short version is that I have ZERO desire to learn to tune ignition dwell - I just don't really give a **** - I just want to get it to work; the dwell table I posted does work well for the application it was tuned on; so take that for what it is worth I guess.
This plus Jeff's earlier posts about ignition dwell is what led me to my widly inaccurate theory I guess...
The short version is that I have ZERO desire to learn to tune ignition dwell - I just don't really give a **** - I just want to get it to work; the dwell table I posted does work well for the application it was tuned on; so take that for what it is worth I guess.
04-26-2009, 03:56 PM
#44
the ls2 coils might not need a full 5ms charge time to deliver the required spark but hey are sure not giving everything they are capable of. they were designed to suit a slow reving v8 with plenty of charge time hence 5ms isn't an issue.
the video I posted shows the test where the dwell time is adjusted. not a huge difference between 3.1 and 5ms.
screen shots.
~2.5ms
~3.1
~5ms
the video I posted shows the test where the dwell time is adjusted. not a huge difference between 3.1 and 5ms.
screen shots.
~2.5ms
~3.1
~5ms
04-26-2009, 05:41 PM
#45
yukons can be MADE to work with FI / 300+g/sec in the torque curve. They do have more potential, but maybe they do not have an advantage over the ls2 for our application? Do 10 lbs and less guys need the full capacity of the yukons? LS2 may be more compatible for us monkey mechanics that dont tune?
I can see the advantage of the yukons on the na car.
Untill I can get this sorted out I went back to oem for now. Saw my a/f's get a point tenth richer---sigh.
olddragger
I can see the advantage of the yukons on the na car.
Untill I can get this sorted out I went back to oem for now. Saw my a/f's get a point tenth richer---sigh.
olddragger
04-26-2009, 06:30 PM
#46
04-27-2009, 01:04 AM
#47
What we have experienced in our research when we were developing coils we were running into numerous issues with ls2 coils among others.
There is an issue and those haven't found out what the real solution is. There may be a fix but in the end some will still have issues but not the same type of issues. New ones will surface.
I am sorry for the issues you guys have been having but with my 2 years of exp with different coils and setups you will find the same thing I did; you are on the right track.
I had numerous issues with my car and finding just the right combination to make it work the way it should be.
Now picking up where others left off.
Hence our delay in releasing our coil kits....we are making this in house, no more micro tech and no one can duplicate it. It really is perfect, I am extremely excited to be bringing this to the community, we are waiting becasue we want it to be right and right the first time and not fumble over ourselves with I didn't know that? And I was unaware of those issues...so on and so forth.
Not to mention the fact that you were pushed to the wolves on your own.
I will let you guys find it out for yourself becasue no one seems to believe me anyway, you are on the right track but in the end you will find yourself having another issue when you change the dwell settings.
There is an issue and those haven't found out what the real solution is. There may be a fix but in the end some will still have issues but not the same type of issues. New ones will surface.
I am sorry for the issues you guys have been having but with my 2 years of exp with different coils and setups you will find the same thing I did; you are on the right track.
I had numerous issues with my car and finding just the right combination to make it work the way it should be.
Now picking up where others left off.
Hence our delay in releasing our coil kits....we are making this in house, no more micro tech and no one can duplicate it. It really is perfect, I am extremely excited to be bringing this to the community, we are waiting becasue we want it to be right and right the first time and not fumble over ourselves with I didn't know that? And I was unaware of those issues...so on and so forth.
Not to mention the fact that you were pushed to the wolves on your own.
I will let you guys find it out for yourself becasue no one seems to believe me anyway, you are on the right track but in the end you will find yourself having another issue when you change the dwell settings.
Last edited by Race Roots; 04-27-2009 at 01:07 AM.
04-27-2009, 01:55 AM
#50
3-wheeler
Join Date: Dec 2005
Location: Phoenix
Posts: 2,734
Likes: 0
Received 0 Likes
on
0 Posts
Kane, it will probably be around 24 hours before I can get any information back to you but here's something for you to consider.
At first, I recall that we used a broad 30% increase in the AP values just to see if the issues we were experiencing were in fact dwell related. We kept everything else the same as our control. A 30% increase did seem to correct any spark blow out on the turbo RX8. I have been using an adapted version of those settings with adjustments made to back the dwell off in the lower and upper RPM range where a stronger spark isn't needed.
At first, I recall that we used a broad 30% increase in the AP values just to see if the issues we were experiencing were in fact dwell related. We kept everything else the same as our control. A 30% increase did seem to correct any spark blow out on the turbo RX8. I have been using an adapted version of those settings with adjustments made to back the dwell off in the lower and upper RPM range where a stronger spark isn't needed.