what cd box to use-is permatune junk?
#17
Instructor
#18
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Maybe some people on this thread can explain to us all why other ignition
units will out perform the original Bosch CD unit.
Rouxzy comments that the Bosch technology is thirty 30 years old and thus implies
that it must be inferior to the newer units. Ask him why ALL OEM car manufacturers
use 100 year old technology on 2003 vehicles, a coil and a switch. And to the others
who make claims about newer technology, let's hear about the REAL facts from
dyno tests and gas analzers versus hyperbole.
First, there's a minimum requirement for an ignition system beyond which the
voltage and energy is a waste, (60 millijoules and about 350 volts on the primary
is more the enough). Second, the multiple sparks are a marketing gimmick and
provide no additional real ignition benefit. If it were as simple as adding multiple
sparks, all OEMs would buy the patent and use it. The key is multiple points of
ignition via twin plugs and NOT delayed sparks at a SINGLE point in the combustion
chamber.
The simple part of the ignition system is developing the spark. The most diifficult
and critical part is the when to spark, the ignition timing map. Check out this
website (www.systemsc.com) on the Technical page (Ignition Systems) for some additional info.
Avoid wasting money on marketing claims which are not supported by REAL facts
and data.
Have Fun
Loren
'88 3.2
units will out perform the original Bosch CD unit.
Rouxzy comments that the Bosch technology is thirty 30 years old and thus implies
that it must be inferior to the newer units. Ask him why ALL OEM car manufacturers
use 100 year old technology on 2003 vehicles, a coil and a switch. And to the others
who make claims about newer technology, let's hear about the REAL facts from
dyno tests and gas analzers versus hyperbole.
First, there's a minimum requirement for an ignition system beyond which the
voltage and energy is a waste, (60 millijoules and about 350 volts on the primary
is more the enough). Second, the multiple sparks are a marketing gimmick and
provide no additional real ignition benefit. If it were as simple as adding multiple
sparks, all OEMs would buy the patent and use it. The key is multiple points of
ignition via twin plugs and NOT delayed sparks at a SINGLE point in the combustion
chamber.
The simple part of the ignition system is developing the spark. The most diifficult
and critical part is the when to spark, the ignition timing map. Check out this
website (www.systemsc.com) on the Technical page (Ignition Systems) for some additional info.
Avoid wasting money on marketing claims which are not supported by REAL facts
and data.
Have Fun
Loren
'88 3.2
#19
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Additional Note;
With regard to m42Racer's comment about the 959 going thru US emission
testing because of the MSD, any good ignition would have been adequate.
If this is one of the 959s mentioned in the Excellence article, the cars were
mickey moused by removing the Bosch Motronic system. The Bosch 959 Motronic
was wired for emissions control and needed a simple EPROM change to have
a fully functional emissions system to pass the EPA emissions test.
Those guys ruined good original 959s because of incompetence. Other shops
have had the cars passed without "ripping" the race 959 Bosch system off and
adding a junk aftermarket system. There are a lot "butchers" out there that
ruin good classic cars, and this is a perfect example.
Have Fun
Loren
'88 3.2
With regard to m42Racer's comment about the 959 going thru US emission
testing because of the MSD, any good ignition would have been adequate.
If this is one of the 959s mentioned in the Excellence article, the cars were
mickey moused by removing the Bosch Motronic system. The Bosch 959 Motronic
was wired for emissions control and needed a simple EPROM change to have
a fully functional emissions system to pass the EPA emissions test.
Those guys ruined good original 959s because of incompetence. Other shops
have had the cars passed without "ripping" the race 959 Bosch system off and
adding a junk aftermarket system. There are a lot "butchers" out there that
ruin good classic cars, and this is a perfect example.
Have Fun
Loren
'88 3.2
#20
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CamB,
That is the unit I bought.
I don't know about other years, but on my '75 it is not a bolt in. It IS a plug in, but the size of the unit makes it interfere physically.
Art
That is the unit I bought.
I don't know about other years, but on my '75 it is not a bolt in. It IS a plug in, but the size of the unit makes it interfere physically.
Art
#21
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Thanks CamB for that link. I couldn't seem to find the page.
EDIT: Cam, I see the unit is made by a company (M&W) in Australia. Do you have a link to that company?
EDIT: Cam, I see the unit is made by a company (M&W) in Australia. Do you have a link to that company?
#22
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Comments about the Performance Developments ignition:
This unit uses "old" technology, inductive discharge (TCI - transistor
controlled ignition), to use the words of others on this thread. As a result,
the ignition pulse width tends to be much shorter than the Bosch CDI.
Also, the rise time of the spark pulse tends to be a lot longer causing
problems for firing fouled plugs which is why Porsche used the CDI
technology.
The Performance Technology unit is basically just a high current ignition
points replacement which is the case for all TCI type units. The energy
being quoted is 100mj and 450 volts. The Bosch CDI has 160mj and
about 400 volts with a spark rise time of less that 100ns and a duration
of 150us. The TCI unit from Performance does not spec either the
rise time or the the spark duration.
Additionally, the Performance unit draws high currents (8 amps) which
may be problem for older Porsches because the ignition current comes
from the ignition switch, since there is no ignition relay.
Have Fun
Loren
'88 3.2
This unit uses "old" technology, inductive discharge (TCI - transistor
controlled ignition), to use the words of others on this thread. As a result,
the ignition pulse width tends to be much shorter than the Bosch CDI.
Also, the rise time of the spark pulse tends to be a lot longer causing
problems for firing fouled plugs which is why Porsche used the CDI
technology.
The Performance Technology unit is basically just a high current ignition
points replacement which is the case for all TCI type units. The energy
being quoted is 100mj and 450 volts. The Bosch CDI has 160mj and
about 400 volts with a spark rise time of less that 100ns and a duration
of 150us. The TCI unit from Performance does not spec either the
rise time or the the spark duration.
Additionally, the Performance unit draws high currents (8 amps) which
may be problem for older Porsches because the ignition current comes
from the ignition switch, since there is no ignition relay.
Have Fun
Loren
'88 3.2
#24
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Lorenfb,
Not sure what you looked at. The unit sold by PD is a CDI unit, not inductive. You may have looked at the Inductive Ignitors they also sell. The CDI unit they sell outperforms the factory Bosch unit, and the Permatune. They also sell 1 CDI for twin plug applications where only one unit is required to drive 2 coils. Maybe take another look.
Not sure what you looked at. The unit sold by PD is a CDI unit, not inductive. You may have looked at the Inductive Ignitors they also sell. The CDI unit they sell outperforms the factory Bosch unit, and the Permatune. They also sell 1 CDI for twin plug applications where only one unit is required to drive 2 coils. Maybe take another look.
#26
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Went to this website:
http://www.performancedevelopments....gnition_cdi.php
The website does not display, maybe, all their products, a little confusing.
The only unit is the PRO10 which is defined as an inductive discharge unit.
You say that it out-performs the Bosch unit. Where is the data? Who says?
Have Fun
Loren
'88 3.2
http://www.performancedevelopments....gnition_cdi.php
The website does not display, maybe, all their products, a little confusing.
The only unit is the PRO10 which is defined as an inductive discharge unit.
You say that it out-performs the Bosch unit. Where is the data? Who says?
Have Fun
Loren
'88 3.2