If anyone does start a dialog w/MSD re: these issues, add some questions about
the wear delivered to components like plugs, rotor, cap, etc. in a street-driven
type environment. What is their recommended change intervals for all these
components after installing a hotter ignition box and/or coil for example. The
extra wear that everyone has witnessed kinda contradicts some of that last
rebuttal - unless they come from the multi-spark below 3000rpm. I wouldn't
expect that much tho. Since they sell components to upgrade part of the system
- do they have any heavy-duty or longer-lasting recommendations to round out the
secondary setup?
Thanks,
Shane
Ronald Wong wrote:
> This would be great to present to MSD to see what kind of rebuttal we would
> get. Would you mind, Chris?
>
> Ron
> 00 PB SLT QC 4X2 5.9 46RE 3.92 LSD
> For modifications see my DML Profile (URL follows)
> http://www.twistedbits.net/WWWProfile/dakota/Kw9pV1EkFeOYY
>
> -----Original Message-----
> From: owner-dakota-truck@buffnet.net
> [mailto:owner-dakota-truck@buffnet.net]On Behalf Of chris@slowcar.net
> Sent: Saturday, June 30, 2001 1:03 AM
> To: dakota-truck@buffnet.net
> Subject: Re: DML: Re: MSD
>
> This is one of the things I never agreed with - 48k vs. 28k going farther,
> etc.
> Here's why:
>
> There are 2 steps to "spark"
>
> - First enough voltage must be developed across the spark plug gap to form a
> plasma.
> The voltage required to induce a plasma is not set by the spark module but
> instead by
> the external conditions of the spark gap. Specifically they are the
> air/fuel ratio, amount
> of H20 vapor and the cylinder pressure. The more humidity the lower the
> plasma inducing
> voltage. The higher the compression ratio (and thereby the pressure) the
> higher the voltage.
> I am unsure of the effect of varying air/fuel mixture, I assume it tracks
> humidity
> (dry gas = higher voltage)
>
> - Second, after the plasma is formed, any excess voltage serves to breakdown
> the plasma and
> arcing occurs (the spark).
>
> 2.) The highest plasma inducing voltage required for motors operating with
> 14:1 compression
> is less than 30kV. And no module can force the gap voltage to a higher
> level. Once the plasma
> breakdown voltage is exceeded the spark gap voltage drops by a factor of
> ~50x and the coil is
> discharged with arcing across the gap.
>
> 3.) After the plasma breakdown, arcing (or spark) occurs. But the voltage at
> which sustained
> arcing occurs is about 1/50 the plasma inducing voltage.
>
> Okay, so what does this mean?
> Aftermarket ignition suppliers refer to the spark module's output voltage.
> This is really meaningless.
> The independent variable is not output voltage. Rather the independent
> variable is the voltage
> required to arc the plasma. Even if they say they can deliver 45kV, in a
> 11:0 compression motor,
> 25kV is all the module will ever deliver.
>
> Chris Bennight
> http://www.slowcar.net
> 66 Charger For Sale
> http://www.slowcar.net/charger
>
> ----- Original Message -----
> From: "Ronald Wong" <ron-wong@home.com>
> To: <dakota-truck@BUFFNET.NET>
> Sent: Saturday, June 30, 2001 2:18 AM
> Subject: RE: DML: Re: MSD
>
> | The difference between a standard MSD box and your standard ignition is a
> | boost in primary voltage. Instead of 12-volts primary power being
> | introduced to the coil, the MSD box boosts the voltage to 270-volts. On
> an
> | MSD Blaster SS coil I believe the 270 gets boosted to 48K-volts secondary.
> | Std ignition and MSD Blaster coil nets about 28K-volts at the plugs. What
> | does all this buy you? Better ignition and more complete combustion.
> | That's why your gap can be opened up with an MSD box. 48K-volts can jump
> | farther than 28K-volts.
> |
> | Ron
> | 00 PB SLT QC 4X2 5.9 46RE 3.92 LSD
> | For modifications see my DML Profile (URL follows)
> | http://www.twistedbits.net/WWWProfile/dakota/Kw9pV1EkFeOYY
> |
> |
> | -----Original Message-----
> | From: owner-dakota-truck@BUFFNET.NET
> | [mailto:owner-dakota-truck@BUFFNET.NET]On Behalf Of Sam South
> | Sent: Friday, June 29, 2001 8:21 PM
> | To: dakota-truck@BUFFNET.NET
> | Subject: Re: DML: Re: MSD
> |
> |
> | > Big difference (that may contribute to this) - '95 was OBD-I, '96+ is
> | OBD-II
> |
> | That's what I'm inclined to believe also, the 98 had the MSD on from
> around
> | 10K until I sold it at 45K and bought the 95, it was on both trucks with
> | fresh Mopar cap/rotors and Mopar/MSD wires, and also on the 95 I've used
> | Accel and Mopar cap and rotor. With all these changes the only real
> | difference I felt was with the MSD box itself. Maybe someone out there
> could
> | verify if there is some contributing factors in the OBD-I vs. the OBD-II
> | systems.
> | Sam South
> | 95 Dak, 5.2L,3.90 LSD,5-speed(Soon to be 360 powered)
> | 14.10@98.05
> | http://www.twistedbits.net/WWWProfile/dakota/Mt5J8FaDfVCv6/
> | http://people.mw.mediaone.net/sawcut64/home.html
> |
> | ----- Original Message -----
> | From: "Andy Levy" <andylevy@yahoo.com>
> | To: <dakota-truck-moderator@bent.twistedbits.net>
> | Sent: Friday, June 29, 2001 10:36 PM
> | Subject: Re: DML: Re: MSD
> |
> |
> | > Sam South wrote on Friday 29 June 2001 09:43 pm:
> | >
> | > > I had one on my 98 3.9 and it "felt" stronger, but when it was
> installed
> | > > on my 95 5.2 it definitely felt like I lost a few ponies. I left it on
> | > > anyway thinking maybe I was wrong about it, but after I saw with my
> own
> | > > eyes the difference it made on Mark Dak(I went with him that day to
> the
> | > > dyno) it's coming off and not going back on. Again I have nothing
> | concrete
> | > > to back this up with on my trucks other then how it "felt".
> | > > Sam South
> | > > 95 Dak, 5.2L,3.90 LSD,5-speed(Soon to be 360 powered)
> | > > 14.10@98.05
> | > > http://www.twistedbits.net/WWWProfile/dakota/Mt5J8FaDfVCv6/
> | > > http://people.mw.mediaone.net/sawcut64/home.html
> | > >
> | > > ----- Original Message -----
> | > > From: <Datstein@aol.com>
> | > > To: <Dakota-truck@buffnet.net>
> | > > Sent: Friday, June 29, 2001 8:29 PM
> | > > Subject: DML: MSD
> | > >
> | > >
> | > >> What gives? I'm saving my sheckles to buy an MSD 6A because of all
> the
> | > > good
> | > >> talk on the DML and now it's robbing horsepower??? There must be
> some
> | > >> correlation between the other mods on the vehicle in question or
> maybe
> | > > it's
> | > >> just the emotional justification that the buyer doesn't want to admit
> | > >> that
> | > >> he/she wasted $150. I for one would like to hear several
> | > >> opinions...especially with dyno results. David
> | > >
> | > >
> | >
> | > --
> | > -andy
> | > andylevy@yahoo.com
> | > http://home.twcny.rr.com/andylevy/dakota/
> | > '99 CC 4x4 318 auto
> |
> |
> |
-- '96 IndyRam-HisIndy-MPI/TB/Pulleys/AccelCoil/MPComp/HookerSuperComps/CompTAs '96 IndyRam-HerIndy-numbered(#142)"Track Truck" '74 Triple-Black Dodge Challenger Rallye 360 home-brew EFI R&D vehicle '68 Black Corvette Convertible 427 (For Sale)
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