[LT1] Can a hotter coil screw up the Optispark?
11-07-2004, 01:08 AM
#1
Le Mans Master
Thread Starter
[LT1] Can a hotter coil screw up the Optispark?
Something like the MSD Blaster GM coil, or the Moroso Pro Coil F, or Hypertech's GM coil? These coils throw about 50% more peak voltage energy at the opti. Can that hurt it or shorten service life?
Main interest is having a coil that keeps up the energy in the higher rpm range. I hear the stock coil starts to peter out around 4000 rpm?
Main interest is having a coil that keeps up the energy in the higher rpm range. I hear the stock coil starts to peter out around 4000 rpm?
11-07-2004, 02:49 AM
#2
Team Owner
Try the LT4 coil.
To me, it makes sense the hotter coils can do damage to the insides of the cap/rotor... that much juice has to go somewhere, arc welding commences...
To me, it makes sense the hotter coils can do damage to the insides of the cap/rotor... that much juice has to go somewhere, arc welding commences...
11-07-2004, 06:34 AM
#4
Le Mans Master
I have been using the msd for about 2 years now without any problems. IMO what will take out the opti is resistance in the system ie, bad wires etc. At least that is what was told to me 20-25 years ago, in a class (1 day) I took from a electronic ignition manufacture. They claimed that poor grounds, bad ignition wires etc, put extra resistance on the electronics and would shorten their lives.
On the other side of this I want to say that after switching the coil I could tell no difference in the car. This was being measured with my butt-o-meter.
On the other side of this I want to say that after switching the coil I could tell no difference in the car. This was being measured with my butt-o-meter.
Last edited by 93 ragtop; 11-07-2004 at 06:37 AM.
11-07-2004, 09:18 AM
#5
Safety Car
As bogus said, the '96 coil and ignition module are hotter and have an extended rpm range to satisfy the higher rpm capabilities of the LT4.
My opinion is an engine that has more horsepower also has higher cylinder pressure (that is why it has more horsepower). With higher cylinder pressure it takes a higher voltage at the spark plug to cause current to flow. This higher voltage is reflected back into the Opti-Spark causing it to eventiually arc internally, which eventually causes carbon tracks to form.
So, higher horsepower and spark plug gaps too wide will cause spark plug voltage to build to the point that it can cause problems in the Opti-Spark.
That been said, a hotter ignition system will feed the higher voltage required in these situations and may cause Opti-Spark problems. But, it is the higher horsepower and spark plug gaps that are the core of the problem.
Taking the high voltage out of the Opti-Spark (Delteq or LTCC) is a much better solution than a hotter coil or CD ignition system.
Tom Piper
My opinion is an engine that has more horsepower also has higher cylinder pressure (that is why it has more horsepower). With higher cylinder pressure it takes a higher voltage at the spark plug to cause current to flow. This higher voltage is reflected back into the Opti-Spark causing it to eventiually arc internally, which eventually causes carbon tracks to form.
So, higher horsepower and spark plug gaps too wide will cause spark plug voltage to build to the point that it can cause problems in the Opti-Spark.
That been said, a hotter ignition system will feed the higher voltage required in these situations and may cause Opti-Spark problems. But, it is the higher horsepower and spark plug gaps that are the core of the problem.
Taking the high voltage out of the Opti-Spark (Delteq or LTCC) is a much better solution than a hotter coil or CD ignition system.
Tom Piper
11-07-2004, 09:58 AM
#6
Drifting
Member Since: Feb 2004
Location: Champaign, IL
Posts: 1,485
Likes: 0
Received 1 Like
on
1 Post
St. Jude Donor '05
Originally Posted by bogus
Try the LT4 coil.
11-07-2004, 09:59 AM
#7
Le Mans Master
Thread Starter
The conversion sounds complicated because Tom Piper said you have to do something about making your own tachometer wire and patching it into the LT4 coil. I am not sure how I would go about that.
Originally Posted by bogus
Try the LT4 coil.
To me, it makes sense the hotter coils can do damage to the insides of the cap/rotor... that much juice has to go somewhere, arc welding commences...
To me, it makes sense the hotter coils can do damage to the insides of the cap/rotor... that much juice has to go somewhere, arc welding commences...
11-07-2004, 10:10 AM
#8
Le Mans Master
Thread Starter
93 ragtop, what spark plug wires are you using with the MSD Blaster GM coil? If you're using stock wires maybe the resistance is too high in the wires to benefit from the coil.
Originally Posted by 93 ragtop
I have been using the msd for about 2 years now without any problems. IMO what will take out the opti is resistance in the system ie, bad wires etc. At least that is what was told to me 20-25 years ago, in a class (1 day) I took from a electronic ignition manufacture. They claimed that poor grounds, bad ignition wires etc, put extra resistance on the electronics and would shorten their lives.
On the other side of this I want to say that after switching the coil I could tell no difference in the car. This was being measured with my butt-o-meter.
On the other side of this I want to say that after switching the coil I could tell no difference in the car. This was being measured with my butt-o-meter.
11-07-2004, 11:07 AM
#9
Team Owner
Member Since: Mar 2001
Location: Cincinnati, Oh USA
Posts: 53,930
Likes: 0
Received 26 Likes
on
23 Posts
It only takes about 5000 volts to jump a plug gap so a coil rated at 100,00 volts only means the coil secondary reaches 100,000 volts if no spark occurs. It is an advertising gimmick for those that do not understand electricity and are impressed with large voltage numbers. The spark energy in a spark coil is 1/2 L x I squared. If you increase L (primary inductance) you will see a decrease in spark energy with increasing rpm. If you increase I (primary current) you will shorten the life of your stock spark control module. GM has made an excellent compromise for maximum spark energy for the full rpm range and a long spark control module life in their high energy ignition system spark coils. Who knows what compromise was made with an aftermarket coil?
I recommend you stick with your stock coil as there isn't a thing wrong with it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!
Oh, and to answer your question, if your wires and plugs are all ok and there are no plug wires that are open circuit, then your optispark will not be harmed by an aftermarket coil. But.....if you have an open circuit, then the coil voltage will rise until a path that can be ionized is found and that might occur inside your optispark and it can cause a carbon track and that will damage your optispark.....and that can happen with EITHER a stock coil OR an aftermarket coil.
I recommend you stick with your stock coil as there isn't a thing wrong with it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!
Oh, and to answer your question, if your wires and plugs are all ok and there are no plug wires that are open circuit, then your optispark will not be harmed by an aftermarket coil. But.....if you have an open circuit, then the coil voltage will rise until a path that can be ionized is found and that might occur inside your optispark and it can cause a carbon track and that will damage your optispark.....and that can happen with EITHER a stock coil OR an aftermarket coil.
Last edited by jfb; 11-07-2004 at 11:13 AM.
11-07-2004, 02:53 PM
#10
Instructor
A hotter coil does not seem to take them out as much as an After market system does.
I get about 14K miles on an Opti in my 95 With MSD 6T. On the other hand my wifes bolt on car with stock ignition got 76k out of the first one and at 126k the second is still going.
MSD show cased a new cap and rotor for the Opti at SEMA. Should work great.
Me? I am stuffing a MSD billet in the back just for spark(opti still used) so I can swap the cap and rotor out with out ripping the front of the motor apart
I get about 14K miles on an Opti in my 95 With MSD 6T. On the other hand my wifes bolt on car with stock ignition got 76k out of the first one and at 126k the second is still going.
MSD show cased a new cap and rotor for the Opti at SEMA. Should work great.
Me? I am stuffing a MSD billet in the back just for spark(opti still used) so I can swap the cap and rotor out with out ripping the front of the motor apart
11-07-2004, 05:46 PM
#11
Le Mans Master
Thread Starter
Where do you learn all this stuff, jfb?
Originally Posted by jfb
It only takes about 5000 volts to jump a plug gap so a coil rated at 100,00 volts only means the coil secondary reaches 100,000 volts if no spark occurs. It is an advertising gimmick for those that do not understand electricity and are impressed with large voltage numbers. The spark energy in a spark coil is 1/2 L x I squared. If you increase L (primary inductance) you will see a decrease in spark energy with increasing rpm. If you increase I (primary current) you will shorten the life of your stock spark control module. GM has made an excellent compromise for maximum spark energy for the full rpm range and a long spark control module life in their high energy ignition system spark coils. Who knows what compromise was made with an aftermarket coil?
I recommend you stick with your stock coil as there isn't a thing wrong with it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!
Oh, and to answer your question, if your wires and plugs are all ok and there are no plug wires that are open circuit, then your optispark will not be harmed by an aftermarket coil. But.....if you have an open circuit, then the coil voltage will rise until a path that can be ionized is found and that might occur inside your optispark and it can cause a carbon track and that will damage your optispark.....and that can happen with EITHER a stock coil OR an aftermarket coil.
I recommend you stick with your stock coil as there isn't a thing wrong with it !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!
Oh, and to answer your question, if your wires and plugs are all ok and there are no plug wires that are open circuit, then your optispark will not be harmed by an aftermarket coil. But.....if you have an open circuit, then the coil voltage will rise until a path that can be ionized is found and that might occur inside your optispark and it can cause a carbon track and that will damage your optispark.....and that can happen with EITHER a stock coil OR an aftermarket coil.
11-09-2004, 06:56 AM
#12
Le Mans Master
Originally Posted by Lone Ranger
93 ragtop, what spark plug wires are you using with the MSD Blaster GM coil? If you're using stock wires maybe the resistance is too high in the wires to benefit from the coil.
11-09-2004, 11:57 AM
#13
Drifting
I don't know if an aftermarket coil will mess anything up but the stock coil (at least in '96) is easily good to 6500rpm.... I know this for a fact.
At least for a stock or close to stock compression ratio. With a slightly smaller plug gap the coil works fine even with a 120RWHP shot of nitrous.
At least for a stock or close to stock compression ratio. With a slightly smaller plug gap the coil works fine even with a 120RWHP shot of nitrous.
11-10-2004, 01:04 AM
#14
Instructor
I have ran my stock system to 7,000 and over 500HP. It sure idles better with a after market system and it makes it more streetable for me Pretty much smooth idle at 900 and a 234/242 cam
Pretty much smooth idle at 900 and a 234/242 cam
