tuning; timing & VE tables
12-19-2012, 01:00 PM
#1
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
tuning; timing & VE tables
93 vett, hot cam, 1.6rr's, LT headers, TF 185 heads, 10.8 comp ratio, no cats, LT1 6 spd, rebuilt 355.
When I got my tune from a mail order tuner the car bucked like a mule in any gear except 6 when below 2000 rpm. He did 3 free retunes and said I was maxing out my stock Bosch 3 injectors. I installed a wide band and data logged too. I am running lean anywhere below 2000rpm, around 15 a/f ratio on average.
I have since adjusted the timing way down (see here for timing tables; mainsparktables_zpsd2e33ef9.png photo by photobam | Photobucket) and bucking is much better. But car still runs lean at idle and below 2000 rpm. At WOT it is super rich, around 9 - 10 a/f ration and has a terrible bog for a split second. Any help would be appreciated.
I can post datamaster logs, or anything else for you too look at.
When I got my tune from a mail order tuner the car bucked like a mule in any gear except 6 when below 2000 rpm. He did 3 free retunes and said I was maxing out my stock Bosch 3 injectors. I installed a wide band and data logged too. I am running lean anywhere below 2000rpm, around 15 a/f ratio on average.
I have since adjusted the timing way down (see here for timing tables; mainsparktables_zpsd2e33ef9.png photo by photobam | Photobucket) and bucking is much better. But car still runs lean at idle and below 2000 rpm. At WOT it is super rich, around 9 - 10 a/f ration and has a terrible bog for a split second. Any help would be appreciated.
I can post datamaster logs, or anything else for you too look at.
12-20-2012, 01:17 PM
#2
Registered User
Join Date: Nov 2007
Posts: 910
Re: tuning; timing & VE tables
What injectors are you running ?? If your log is .csv or a Datamaster "DA" .uni I can take a look. Send log to ' datalogs@comcast.net) . Please put your ID in the subject line.
12-21-2012, 11:46 AM
#4
Registered User
Join Date: Nov 2007
Posts: 910
Re: tuning; timing & VE tables
here is a link to your log for others to access.. https://www.dropbox.com/s/qpr2cetyde...018%202012.uni DataMaster 'DA' is needed for a '93 ECM... Download is free..
It's a long log and not any big obvious thing that sticks out that would cause bucking at low loads. Unfortunately OBD1 does not record any high voltage, ICM/coil/rotor/plug wire/or plug failures. So that has to be looked at using old school methods. Burnt wires, corrosion, sparks in the dark, cracked plugs, etc
As far as the log... noticed it took 7 mins to get into closed loop, does vett have single wire O2's like F-Body, what about headers ?? .
1- You injectors are maxing out, you punched it in 1st around record #8343 and you injector duty cycle (DC) hit 96% at 5600 RPM, 85% is considered pushing an injector to it's limit. Assuming you FP is supplying enough fuel & pressure you need bigger injectors..However they would not cause low end lean problem. They are down well below 20% DC at normal operation.
2 - About timing, I have a HotCam w/1.6rr's, but my intake and heads are stock, not modified like yours. I run 34* closed TPS timing at 800-1200 RPM, you are only running 29*. You main timing table is also low, you are averaging 11-13* below what I run in the 25-85 Kpa ranges and actually you are running 7-9* below stock settings.
3- Your idle is a little fast set at 888 RPM, MAP is good at 43, but you have a 10% split BLM problem at idle and low engine loads. The left is adding 3.7% fuel and right is pulling 6.5% at idle and it stays that way till you pass into high end. But is is there at mild cruising. Do you have an aftermarket TB ?. At idle your TPS voltage is good at .53 volts, however your IAC is around 20, so you're not getting a lot of idle air from the idle plenums. That will cause splits.
I would concentrate on getting a smooth idle at 750-800 RPM, try timing at 32-34* in the 600, 800, 1200 closed TPS ranges, Maybe close TB a little, you can go to 4.5 volts and that would get the IAC counts up. Aftermarket Tb may require slotting the mounts to get voltage in spec and IAC up in the 40's.
Then see what the IDle BLm's look like. If split disappears then start looking at VE tables, and getting your main & ectended timing back up.
It's a long log and not any big obvious thing that sticks out that would cause bucking at low loads. Unfortunately OBD1 does not record any high voltage, ICM/coil/rotor/plug wire/or plug failures. So that has to be looked at using old school methods. Burnt wires, corrosion, sparks in the dark, cracked plugs, etc
As far as the log... noticed it took 7 mins to get into closed loop, does vett have single wire O2's like F-Body, what about headers ?? .
1- You injectors are maxing out, you punched it in 1st around record #8343 and you injector duty cycle (DC) hit 96% at 5600 RPM, 85% is considered pushing an injector to it's limit. Assuming you FP is supplying enough fuel & pressure you need bigger injectors..However they would not cause low end lean problem. They are down well below 20% DC at normal operation.
2 - About timing, I have a HotCam w/1.6rr's, but my intake and heads are stock, not modified like yours. I run 34* closed TPS timing at 800-1200 RPM, you are only running 29*. You main timing table is also low, you are averaging 11-13* below what I run in the 25-85 Kpa ranges and actually you are running 7-9* below stock settings.
3- Your idle is a little fast set at 888 RPM, MAP is good at 43, but you have a 10% split BLM problem at idle and low engine loads. The left is adding 3.7% fuel and right is pulling 6.5% at idle and it stays that way till you pass into high end. But is is there at mild cruising. Do you have an aftermarket TB ?. At idle your TPS voltage is good at .53 volts, however your IAC is around 20, so you're not getting a lot of idle air from the idle plenums. That will cause splits.
I would concentrate on getting a smooth idle at 750-800 RPM, try timing at 32-34* in the 600, 800, 1200 closed TPS ranges, Maybe close TB a little, you can go to 4.5 volts and that would get the IAC counts up. Aftermarket Tb may require slotting the mounts to get voltage in spec and IAC up in the 40's.
Then see what the IDle BLm's look like. If split disappears then start looking at VE tables, and getting your main & ectended timing back up.
Last edited by bobdec; 12-21-2012 at 11:57 AM.
12-21-2012, 02:10 PM
#5
Administrator
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: tuning; timing & VE tables
Maybe it's just my version of the 93 version of DM, but I see a lot of different results. He has an M6, but the data log appears to be set to "Y-Car A/T", yielding strange indications of what gear it is in.
It took 424 seconds to go into closed loop because that's how long it took the coolant to reach 140*F, one of the three conditions that has to be met for closed loop enable. Check the t'stat to make sure it's working. Fans are not running, so it may be the t'stat. The O2's appear to be active much earlier, so it doesn't look like they are the cause of the delay.
1 - Datamaster seems to overstate fuel injector duty cycle. I see this all the time. It will report in excess of 100% when the engine is not running lean on fuel. In the area you mention with the 90+% DC's, both O2 sensors are reporting 950+ mV. Definitely not running out of fuel. Same story at record 16915..... 98.3% DC, but O2's are 955 and 963 mV. It's running very rich at WOT as reported by his wide band. No real indication the injectors need to be bigger.
3 - Take a look at the Cell 16 BLM's at the end of the data log... left side is 146 (adding 14%, right side is 100 (below the normal 108 programming limit, subtracting 22%). At record 20668, something happens that causes the left O2 sensor to drop like a rock... as low as 36mV and it hangs low. There is evidence of that happening repeatedly when it's idling. Go back to the open loop area (e.g. record 1268) and the left O2 is hanging at ~80mV, and the right O2 is hanging at over 900mV. Yet at record 1512 the left O2 is right up there with the right O2.
There are repeated data errors throughout the log... speed suddenly jumps to 254 MPH, other anomalies, sometimes coupled with false indications of DTC's..
It took 424 seconds to go into closed loop because that's how long it took the coolant to reach 140*F, one of the three conditions that has to be met for closed loop enable. Check the t'stat to make sure it's working. Fans are not running, so it may be the t'stat. The O2's appear to be active much earlier, so it doesn't look like they are the cause of the delay.
1 - Datamaster seems to overstate fuel injector duty cycle. I see this all the time. It will report in excess of 100% when the engine is not running lean on fuel. In the area you mention with the 90+% DC's, both O2 sensors are reporting 950+ mV. Definitely not running out of fuel. Same story at record 16915..... 98.3% DC, but O2's are 955 and 963 mV. It's running very rich at WOT as reported by his wide band. No real indication the injectors need to be bigger.
3 - Take a look at the Cell 16 BLM's at the end of the data log... left side is 146 (adding 14%, right side is 100 (below the normal 108 programming limit, subtracting 22%). At record 20668, something happens that causes the left O2 sensor to drop like a rock... as low as 36mV and it hangs low. There is evidence of that happening repeatedly when it's idling. Go back to the open loop area (e.g. record 1268) and the left O2 is hanging at ~80mV, and the right O2 is hanging at over 900mV. Yet at record 1512 the left O2 is right up there with the right O2.
There are repeated data errors throughout the log... speed suddenly jumps to 254 MPH, other anomalies, sometimes coupled with false indications of DTC's..
12-21-2012, 03:50 PM
#6
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
Re: tuning; timing & VE tables
Thanks for taking a long look at my data log, both of you.
1. I noticed after the log that I forgot to check the 6 spd tranny for the vett. my bad.
2. That last part of the log is me driving up my long driveway. That is when the car bucks the most, have to let the clutch out several times to keep it from jerking you thru the windshield. The tune from the tuner had all the stock timing tables and I kept bringing the timing down, that has at least made it driveable as to the bucking, it is hardly noticeable now unless below 1000 rpm. I also had knock counts in the 5- 6000range.
3. I know I am rich at WOT I can see it with the wide band and lean at any cruise speed, around 1200 - 2000 rpm, that runs about 15. The wide band never reads below 14.7, it is always above that.
4. My problem is that I really don't know where to start with the fueling, I wish someone would post a VE table that has a hot cam and some head work that runs good, that at least might give me a start.
5. ICM is new, new Taylor wires, new plugs to match the TF heads, I installed heated Delco 02's, Opti is new MSD vented. The day I did the log it was pretty cold out, 25 or so degrees so it's no wonder it took a while to get to closed loop, normally it hardly takes any time at all.
6. I do notice that in open loop, when the wide band reads around 13.5 just after start up that it runs much better than when it goes into closed and starts showing 15 and above on the wide band.
Thanks for the comments guys, where do I go from here?
1. I noticed after the log that I forgot to check the 6 spd tranny for the vett. my bad.
2. That last part of the log is me driving up my long driveway. That is when the car bucks the most, have to let the clutch out several times to keep it from jerking you thru the windshield. The tune from the tuner had all the stock timing tables and I kept bringing the timing down, that has at least made it driveable as to the bucking, it is hardly noticeable now unless below 1000 rpm. I also had knock counts in the 5- 6000range.
3. I know I am rich at WOT I can see it with the wide band and lean at any cruise speed, around 1200 - 2000 rpm, that runs about 15. The wide band never reads below 14.7, it is always above that.
4. My problem is that I really don't know where to start with the fueling, I wish someone would post a VE table that has a hot cam and some head work that runs good, that at least might give me a start.
5. ICM is new, new Taylor wires, new plugs to match the TF heads, I installed heated Delco 02's, Opti is new MSD vented. The day I did the log it was pretty cold out, 25 or so degrees so it's no wonder it took a while to get to closed loop, normally it hardly takes any time at all.
6. I do notice that in open loop, when the wide band reads around 13.5 just after start up that it runs much better than when it goes into closed and starts showing 15 and above on the wide band.
Thanks for the comments guys, where do I go from here?
12-22-2012, 09:30 AM
#7
Administrator
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: tuning; timing & VE tables
You do realize that 15:1 A/F ratio is not rich or lean for "normal" (not WOT) driving? The PCM is hard coded to maintain 14.7:1 at anything other then cold start or power enrichment (PE) mode (WOT, for simplification). 15.0:1 would not indicate a problem and is not lean.
That is within the normal tolerance. The only reason they pick 14.7:1 is because that is the A/F ratio that produces the least TOTAL amount of the pollutants HC, CO and NOx. You could get better fuel mileage at a leaner A/F ratio, but that would cause NOx to increase, while HC and CO would be dropping.
You lean out the WOT target A/F ratio with the PE mode tables, at least in the MAF setups. I would think that the 93's speed-density would work similarly.
That is within the normal tolerance. The only reason they pick 14.7:1 is because that is the A/F ratio that produces the least TOTAL amount of the pollutants HC, CO and NOx. You could get better fuel mileage at a leaner A/F ratio, but that would cause NOx to increase, while HC and CO would be dropping.
You lean out the WOT target A/F ratio with the PE mode tables, at least in the MAF setups. I would think that the 93's speed-density would work similarly.
12-22-2012, 01:43 PM
#8
Registered User
Join Date: Nov 2007
Posts: 910
Re: tuning; timing & VE tables
I was so concentrated on the weird O2 readings at the start up that I never looked at the coolant temp.. Good catch. For the first 7 mins right O2 was pinned around 950 mv and left started reading rich and then went down near 50 Mv w/5 short spikes for that 7 mins. Very strange readings and would indicate crappy running during that time. During that time you are using the stored LT BLM numbers to adjust fueling and your LT BLM numbers stink.. see split BLM stuff down further. Even w/coolant still cold seems like a long time for O2's to start switching. Almost like heaters are not working..but that's something to look at later on, if it really is a problem.
What I would fix first, starting at idle ... Because of the open loop up front I concentrated on the 2 mins of closed loop idle at the end of the trace starting at record 20009. It shows you were idling, shut it down, and then restarted it. It also shows your split BLM's that have to be fixed before you can start tuning the VE tables. At log record #19910 your LT counts are showing PCM is adding 12% fuel to left side and the PCM is pulling 20% of fuel from the right side, that indicates a major problem. With that problem if you change the VE table one side may get better, but the other will get worse. So you need to get the split BLM's in order prior to tuning VE tables. What side is your wideband on, and what is it reading at a warmed up idle ? Mild split BLM's usually mean not enough idle air is flowing through the idle air plenums in the intake manifold. Resulting with incorrect air distribution to all the cylinders, shows up on modded engines w/cams, etc. This air enters through a port on the stock TB that mates w/the air plenum hole in the intake manifold. The air flow is controlled by the IAC, and your IAC counts are low (16-20) at idle. If you search on split BLM's you will get quite a few hits. Aftermarket TB's that don't distribute idle air to the plenum correctly are sometimes to blame, that's why I asked what TB you are running. What bank do you have the WB installed ?? How are you tuning, burning chips or do you have an emulator ??
What I would fix first, starting at idle ... Because of the open loop up front I concentrated on the 2 mins of closed loop idle at the end of the trace starting at record 20009. It shows you were idling, shut it down, and then restarted it. It also shows your split BLM's that have to be fixed before you can start tuning the VE tables. At log record #19910 your LT counts are showing PCM is adding 12% fuel to left side and the PCM is pulling 20% of fuel from the right side, that indicates a major problem. With that problem if you change the VE table one side may get better, but the other will get worse. So you need to get the split BLM's in order prior to tuning VE tables. What side is your wideband on, and what is it reading at a warmed up idle ? Mild split BLM's usually mean not enough idle air is flowing through the idle air plenums in the intake manifold. Resulting with incorrect air distribution to all the cylinders, shows up on modded engines w/cams, etc. This air enters through a port on the stock TB that mates w/the air plenum hole in the intake manifold. The air flow is controlled by the IAC, and your IAC counts are low (16-20) at idle. If you search on split BLM's you will get quite a few hits. Aftermarket TB's that don't distribute idle air to the plenum correctly are sometimes to blame, that's why I asked what TB you are running. What bank do you have the WB installed ?? How are you tuning, burning chips or do you have an emulator ??
12-22-2012, 02:36 PM
#9
Administrator
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: tuning; timing & VE tables
The O2 sensors "switch" because in closed loop the PCM is toggling the A/F ratio back and forth from slightly rich to slightly lean. That is required for the cat(s) to work. You won't see them switching in open loop.
A cold O2 sensor reads about 450mV.... the bias voltage supplied by the PCM. As they start to heat up, they start to generate their own voltage, based on the relative molar concentration of oxygen on the inside (ambient air) and outside (exhaust) of the thimble, that adds to or subtracts from the bias voltage. If an O2 sensor is at 950mV in closed loop, it's hot and it's working, unless there is voltage leaking from the heater circuits, definitely not a possibility with the 93. The fact that the O2 reading suddenly drops has nothing to do with slow switching... it's indicating that the exhaust suddenly went very lean (or the signal wire is intermittently shorting to ground).
I don't see any evidence of anything but the slow coolant heat up causing the extended period to closed loop. It goes closed loop the instant the coolant hits 140.0*F.
A cold O2 sensor reads about 450mV.... the bias voltage supplied by the PCM. As they start to heat up, they start to generate their own voltage, based on the relative molar concentration of oxygen on the inside (ambient air) and outside (exhaust) of the thimble, that adds to or subtracts from the bias voltage. If an O2 sensor is at 950mV in closed loop, it's hot and it's working, unless there is voltage leaking from the heater circuits, definitely not a possibility with the 93. The fact that the O2 reading suddenly drops has nothing to do with slow switching... it's indicating that the exhaust suddenly went very lean (or the signal wire is intermittently shorting to ground).
I don't see any evidence of anything but the slow coolant heat up causing the extended period to closed loop. It goes closed loop the instant the coolant hits 140.0*F.
12-26-2012, 07:12 PM
#10
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
Re: tuning; timing & VE tables
The wide band 02 is on the pass side right after the regular 02. I have a stock TB bored to 52 mm. I may need to open up the IAC hole a little for the hot cam, I have heard of others doing that.
I am burning chips to change the tune.
I know that the motor will run with the A/F ration at 15 and above but it runs much better when it is still in open loop and running around 13.7-14.3, it runs MUCH better. I really don't care that much about gas mileage because I only drive a few thousand miles a year. According to my wide band I never run below 14.7 to one, it is the lowest number and fluctuates above that to 16.0 or so. At WOT it is very rich running in the low 10's. I am thinking I need to lean out the Kpa range of 85 and above and add fuel in the 25 - 65 range, am I right in thinking that?
Has anyone ever tried wiring both right and left 02's togeather? Would that eliminate split BLM's or just cause major problems? Seems like something worth a try.
Thanks for the help guys, keep the info comming, really appreciate it.
I am burning chips to change the tune.
I know that the motor will run with the A/F ration at 15 and above but it runs much better when it is still in open loop and running around 13.7-14.3, it runs MUCH better. I really don't care that much about gas mileage because I only drive a few thousand miles a year. According to my wide band I never run below 14.7 to one, it is the lowest number and fluctuates above that to 16.0 or so. At WOT it is very rich running in the low 10's. I am thinking I need to lean out the Kpa range of 85 and above and add fuel in the 25 - 65 range, am I right in thinking that?
Has anyone ever tried wiring both right and left 02's togeather? Would that eliminate split BLM's or just cause major problems? Seems like something worth a try.
Thanks for the help guys, keep the info comming, really appreciate it.
12-26-2012, 07:35 PM
#11
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
Re: tuning; timing & VE tables
What do you guys think of this, running in open loop all the time?
I got a wideband, switched to an Open Loop tune, and have never looked back.
The car runs much better. No bucking at low RPMs in parking lots and such. It was really easy to dial her in on an open loop tune. Took me maybe 3 reflashes and logs to get her right.
I think with my tight LSA, 108, and it being a big lift cam, .600, .600, a lot of unburned fuel was going through the exhaust. The 02's would try to correct it and lean it out too much. The car just couldn't compensate for it.
When I went to an open loop tune, it instantly ran significantly better. The more I richened the mixture (based on my wideband readings), the better she drives on under normal driving. I think I cruise in the mid 13's AFR (versus 14.7), and WOT at around 12.8-13.0
Bottom line, my 02's were robbing my car of fuel. Open Looped her and it has fantastic driveability.
I got a wideband, switched to an Open Loop tune, and have never looked back.
The car runs much better. No bucking at low RPMs in parking lots and such. It was really easy to dial her in on an open loop tune. Took me maybe 3 reflashes and logs to get her right.
I think with my tight LSA, 108, and it being a big lift cam, .600, .600, a lot of unburned fuel was going through the exhaust. The 02's would try to correct it and lean it out too much. The car just couldn't compensate for it.
When I went to an open loop tune, it instantly ran significantly better. The more I richened the mixture (based on my wideband readings), the better she drives on under normal driving. I think I cruise in the mid 13's AFR (versus 14.7), and WOT at around 12.8-13.0
Bottom line, my 02's were robbing my car of fuel. Open Looped her and it has fantastic driveability.
12-26-2012, 10:34 PM
#12
Administrator
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: tuning; timing & VE tables
If you have a high overlap cam, you will be flowing unburned fuel and air out the exhaust valve during overlap. The O2 sensor can only "see" the air, so it would report lean and the ECM would try and richen it up. The sensor can not measure unburned fuel, only the oxygen in the air.
This is confusing... when you said you have a "hot cam" did you mean the LT4 HOT cam? If not, your posts are very misleading. If you are running a big cam, you have to provide that info up front. That makes a huge difference in solving the problem.
12-27-2012, 09:28 AM
#13
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
Re: tuning; timing & VE tables
Sorry I messed up, the following was a quote from a search on "split BLM's" that I found intersting, just wanted to know what you think of running in open loop all the time?
("The car runs much better. No bucking at low RPMs in parking lots and such. It was really easy to dial her in on an open loop tune. Took me maybe 3 reflashes and logs to get her right.
I think with my tight LSA, 108, and it being a big lift cam, .600, .600, a lot of unburned fuel was going through the exhaust. The 02's would try to correct it and lean it out too much. The car just couldn't compensate for it.
When I went to an open loop tune, it instantly ran significantly better. The more I richened the mixture (based on my wideband readings), the better she drives on under normal driving. I think I cruise in the mid 13's AFR (versus 14.7), and WOT at around 12.8-13.0
Bottom line, my 02's were robbing my car of fuel. Open Looped her and it has fantastic driveabiliy")
All that was a quote. I have the LT4 hot cam, not near as big as the cam the guy is running in the quote. Hope that clears that up, my bad.
("The car runs much better. No bucking at low RPMs in parking lots and such. It was really easy to dial her in on an open loop tune. Took me maybe 3 reflashes and logs to get her right.
I think with my tight LSA, 108, and it being a big lift cam, .600, .600, a lot of unburned fuel was going through the exhaust. The 02's would try to correct it and lean it out too much. The car just couldn't compensate for it.
When I went to an open loop tune, it instantly ran significantly better. The more I richened the mixture (based on my wideband readings), the better she drives on under normal driving. I think I cruise in the mid 13's AFR (versus 14.7), and WOT at around 12.8-13.0
Bottom line, my 02's were robbing my car of fuel. Open Looped her and it has fantastic driveabiliy")
All that was a quote. I have the LT4 hot cam, not near as big as the cam the guy is running in the quote. Hope that clears that up, my bad.
Last edited by chalk; 12-27-2012 at 09:31 AM.
12-27-2012, 09:50 AM
#14
Registered User
Thread Starter
Join Date: Jan 2009
Location: missouri
Posts: 17
Re: tuning; timing & VE tables
The principal I was trying to point out and ask about in the quote is the idea that even though his cam is much bigger than mine and much narrower lobe separation (108 vs 112 for my hot cam) is this; even the hot cam has some unburned fuel flowing out the headers, this would cause the 02's to show a slightly rich condition, the computer would pull fuel when actually I am still running lean. I know that the "ideal" fuel air ratio is 14.7 but that is in the framework of emissions, not performance right? All I know for sure is that my car runs MUCH better at 14.0 to 14.3, the question is how do I get the computer to set that air fuel ratio? Is it the VE talbes or does the computer always come back to 14.7?
12-27-2012, 10:23 AM
#15
Administrator
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 70,646
Re: tuning; timing & VE tables
even the hot cam has some unburned fuel flowing out the headers, this would cause the 02's to show a slightly rich condition, the computer would pull fuel when actually I am still running lean.
I already explained this in the previous post, but it appears you don't want to believe this. There's not much more I can do to help you.
I'm still totally confused.... when you mentioned the 108 LSA, were you talking about someone else's cam..... Confusing as hell.
Good luck.