High-Voltage Coil Creates Hole in Pistons?

64bird wrote:
 >
 > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole
 > in stock pistons. The idea is that the engines were not designed to
 > handle more than 30,000 volts. I just want to know if anyone has an
 > opinion about this? Do you agree with this assessment?

I can't see why an arc would prefer to jump a relatively
large distance to a piston top that's not as well grounded
as it would to the small distance to the perfectly grounded
spark plug tip.

JazzMan
--
**********************************************************
Please reply to jsavage"at"airmail.net.
Curse those darned bulk e-mailers!
**********************************************************
"Rats and roaches live by competition under the laws of
supply and demand. It is the privilege of human beings to
live under the laws of justice and mercy." - Wendell Berry
**********************************************************<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

On Sat, 26 Mar 2005, 64bird wrote:

 > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole in
 > stock pistons. The idea is that the engines were not designed to handle
 > more than 30,000 volts. I just want to know if anyone has an opinion
 > about this? Do you agree with this assessment?

Of course not. It is based on gross ignorance of how secondary ignition
voltage is determined. Putting in a "high voltage" coil and changing
nothing else won't change the secondary voltage one bit. Opening the spark
plug gaps will increase the voltage. The spark will NEVER jump to the
piston top unless the spark plug's side electrode is missing (as in
"gone", broken off).

The power (volts x amps) required to jump any given plug gap under any
given conditions is constant. You cannot "force" more volts or more amps
through the gap, for as soon as the power reaches that required to jump
that particular gap, it will jump.

A "high performance" ignition system *can* supply greater voltage and/or
current, but that doesn't mean that it will. The difference isn't what
goes across the gap of the spark plug under ordinary circumstances, it's
what happens under extraordinary circumstances.

Increasing the spark plug gap, increasing the compression, running a dirty
spark plug (either through neglect or because some other thing you've
changed allows the plugs to get dirty, e.g. a "big" camshaft left to
idle).all these things increase the amount of power required to jump the
gap. A stock ignition system may not be able to provide that much power,
with the result being a misfire. A high-performance ignition system has
greater power potential and so will go ahead and fire the plug.

This is very, very commonly misunderstood, thanks in large part to the
marketing tactics used in selling "high performance" (actually high
performance POTENTIAL) ignition components.

DS<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

On 26 Mar 2005 19:39:51 -0800, "64bird" <rbadra.DeleteThis@yahoo.com> wrote:

 >I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 >intake, carb, and cam. I read a post somewhere that adding a
 >high-voltage coil can cause the spark to jump and thus burning a hole
 >in stock pistons. The idea is that the engines were not designed to
 >handle more than 30,000 volts. I just want to know if anyone has an
 >opinion about this? Do you agree with this assessment?

If you replaced your stock coil with something along the lines of an
idustrial arc welder you might have a problem but no ignition coil is
going to burn a hole in your piston.

Steve B.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

Thanks for all the input. I'll install the coil and electonic ignition
tomorrow.
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

64bird wrote:
 > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole
 > in stock pistons. The idea is that the engines were not designed to
 > handle more than 30,000 volts.

Engines have no problems handling 80KV (the highest voltage I've heard
being used intentionally), but some ignition systems can't stand more
than about 35KV-40KV and will leak electricity through the wire
insulation, boots, distributor coil, and rotor (leaks cause those 2 to
crack and require replacement) and sometimes even cause an ion cloud
inside the cap that can shut off the engine temporarily (a reason for
very large diameter caps).

Plugs can typically fire at 5KV-20KV, and high-voltage coils generally
aren't a good way to improve ignition, but solid-state ignition is,
mostly since it lets the voltage turn on much more quickly and makes
the plugs fire before spark energy is drained off by deposits on the
plugs. CD ignition turns on the fastest, but for normal use it's not
an improvement over other solid-state ignition, and if you try it be
sure it's designed to limit its voltage to under 40KV or so.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

"64bird" <rbadra DeleteThis @yahoo.com> wrote in message
news:1111894791.774707.115430@o13g2000cwo.googlegroups.com...
 >I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole
 > in stock pistons. The idea is that the engines were not designed to
 > handle more than 30,000 volts. I just want to know if anyone has an
 > opinion about this? Do you agree with this assessment?
 >


Holes in pistons would not be caused by a "high energy ignition system" but
usually
by a overly lean air/fuel mix in the cylinders, like an intake leak or over
lean carb mixture.

just a bit of common engine performance 101<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

"Daniel J. Stern" wrote:
 >
 > On Sat, 26 Mar 2005, 64bird wrote:
 >
  > > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
  > > intake, carb, and cam. I read a post somewhere that adding a
  > > high-voltage coil can cause the spark to jump and thus burning a hole in
  > > stock pistons. The idea is that the engines were not designed to handle
  > > more than 30,000 volts. I just want to know if anyone has an opinion
  > > about this? Do you agree with this assessment?
 >
 > Of course not. It is based on gross ignorance of how secondary ignition
 > voltage is determined. Putting in a "high voltage" coil and changing
 > nothing else won't change the secondary voltage one bit. Opening the spark
 > plug gaps will increase the voltage. The spark will NEVER jump to the
 > piston top unless the spark plug's side electrode is missing (as in
 > "gone", broken off).

100% Correct.

 >
 > The power (volts x amps) required to jump any given plug gap under any
 > given conditions is constant. You cannot "force" more volts or more amps
 > through the gap, for as soon as the power reaches that required to jump
 > that particular gap, it will jump.

Actually it is voltage only. The breakdown voltage required to ionize
the path and create the spark is constant, the current passing through
that ionized path and therefore the energy generated in the spark is
variable.

Consult the specs on any constant current welding power source (Stick /
TIG). You can hold a constant arc length which will determine the
voltage potential across the arc, while widely varying the current
flowing which will vary the amount of heat being applied to the weld
(TIG foot pedal).

 >
 > A "high performance" ignition system *can* supply greater voltage and/or
 > current, but that doesn't mean that it will. The difference isn't what
 > goes across the gap of the spark plug under ordinary circumstances, it's
 > what happens under extraordinary circumstances.

One thing that a "high performance" ignition could do is reduce fouling
of plugs by providing a higher current to the spark, increasing the
probability that contaminants will be burned off of the plug electrodes.

 >
 > Increasing the spark plug gap, increasing the compression, running a dirty
 > spark plug (either through neglect or because some other thing you've
 > changed allows the plugs to get dirty, e.g. a "big" camshaft left to
 > idle).all these things increase the amount of power required to jump the
 > gap. A stock ignition system may not be able to provide that much power,
 > with the result being a misfire. A high-performance ignition system has
 > greater power potential and so will go ahead and fire the plug.

Voltage, not power. Contaminants provide insulation increasing the
breakdown voltage. A higher voltage is required to create the spark. A
higher current spark may be able to burn off some of the contaminants.

 >
 > This is very, very commonly misunderstood, thanks in large part to the
 > marketing tactics used in selling "high performance" (actually high
 > performance POTENTIAL) ignition components.
 >
 > DS

Key point - Never trust marketing drivel. The product may well be good,
but try to find true specifications or "white papers" written by
engineers, not marketers.

Pete C.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

64bird wrote:

 > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole
 > in stock pistons. The idea is that the engines were not designed to
 > handle more than 30,000 volts. I just want to know if anyone has an
 > opinion about this? Do you agree with this assessment?
 >

Seems to me there are other things the spark can jump to other than the
piston. The gap should be much less than distance from spark plug
electrode to piston. Why is it not jumping the spark gap? If it jumps
that, it won't go to piston.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

Not possible. And those high-voltage Pep Boys special coils are
nothing more that a way to separate you from your money.
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

64bird wrote:

 > I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 > intake, carb, and cam. I read a post somewhere that adding a
 > high-voltage coil can cause the spark to jump and thus burning a hole
 > in stock pistons. The idea is that the engines were not designed to
 > handle more than 30,000 volts. I just want to know if anyone has an
 > opinion about this? Do you agree with this assessment?
 >

Complete horsefeathers.

However, there's no need for these "super duper monster mega coils!"
that the speed shops like to sell. A number of years ago, we were
looking for an automotive coil to use in a piece of research equipment
(completely non automobile related) and we bought an measured quite a
few to see what the peak voltage they could put out was. The best
performer? A generic stock-looking coil from K-mart. The worst
performer? That gigantic bright yellow plastic cased coil Accel used to
sell.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

In article <1111894791.774707.115430.DeleteThis@o13g2000cwo.googlegroups.com>,
rbadra.DeleteThis@yahoo.com says...
 >
 >I have a 64 Thunderbird with a rebuilt 390 (stock) with aftermarket
 >intake, carb, and cam. I read a post somewhere that adding a
 >high-voltage coil can cause the spark to jump and thus burning a hole
 >in stock pistons. The idea is that the engines were not designed to
 >handle more than 30,000 volts. I just want to know if anyone has an
 >opinion about this? Do you agree with this assessment?
 >

Totally bogus!!!!!!!! The spark will only jump to the gap of
the plug because it is closer, and, there isn't enough spark energy
to do that kind of damage even if you broke off the ground side
of the gap, and it did arc to the piston (Which it still won't)<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons? 

We used auto coils for a ESD torture test box several years ago. We
found that the best thing for our purpose was a double-top-tit round
coil used on Onan stationary engines. One of the guys in the shop had a
homemade air boat with a four cylinder Continental with a homemade
ignition that used four of these. Each cylinder had two plugs, but
instead of one coil per jug, he found that a arrangement using one coil
for two cylinders each,doubled, and fired in pairs (the 'wasted spark')
worked best. The stock magnetoes were almost a thousand dollars
each-his homemade arrangement cost $100.
 >> Stay informed about: High-Voltage Coil Creates Hole in Pistons?