Re: Slight high speed miss sometimes
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Re: Slight high speed miss sometimes




I copied this from the 4 Seconds Flat web site. your using the MP distributor, right?

<http://www.4secondsflat.com/Mission%2520Ignition.html>
<http://www.4secondsflat.com/ Technical_Information_for_Ignition_and_Carburetion.html>

ever heard this "I have a high speed miss I just can't find".....


Cap/Rotor Phasing:

This is another part of the ignition tune-up that is almost never addressed. So called Super Tune shops are aware of this inherent problem with Mopar distributors (and others) and it's one of the first things they check.

Simply this is getting the spark signal to the plug by aligning the rotor and cap contacts so the spark travels to the plug at the instant that the two components are aligned or phased.

The Mopar distributors almost never do this, the rotor is either not yet at the contact or it has long since past it's optimum point. What this does is cause the spark to have to jump or arch to the cap, this causes heat energy. If we go back to basic physics we know that "Energy cannot be created or destroyed it can only change form" so what we do here is convert electrical energy to heat energy and effectively reduce the power of the spark as RPM increases and pressure in the cylinder increases causing a higher resistance for the plugs the spark efficiency is drastically reduced...result....poor performance...lost HP and tork.

The cause of this phasing problem is multiple, the biggest thing we find is the vacuum advance plate on a Mopar distributor is really a poor design allowing it to tip and wobble in the distributor housing....when you get your distributor back from us you'll find that plate welded solid and the advance curve is controlled by the weights and springs. Bad bushings, worn gears, poor factory tolerance, cheap caps and rotors can all contribute to or multiply the phasing problems.

It's very common to find a Mopar distributor with the phasing so far off that at around 5000 RPM and up the rotor will get confused and start arching to either the contact ahead or behind it's position....ever heard this "I have a high speed miss I just can't find".....

I had this problem.. and so I welded my vacuum advance plate and did the Don D. tune-up and all is good. (o:
... relatively

Schuyler 62 Dodge Dart 440 wagon w/ Poly 318
 <http://www.1962to1965mopar.ornocar.org/ml-wrobel62.html>
FYI - I Do the Decal designs for the Poly head 318 and more! email me with your needs -
 <sky62@xxxxxxxxxxxxx>



On May 7, 2009, at 10:02 AM, Rich Kinsley wrote:


Actually I rewired the entire car except the dome light and heater
controls. I don't have it hooked up anyway. I grounded everything I
could think of, even me :-) My new alternator is 90amps and I certainly
have juice now. My gauge shows a steady 14volts almost always. I
certainly will recheck things just for good luck but I really suspect
the ECM. It was abused previously.

Rich Kinsley '64 Dodge Polara 4dr 318poly w/goodies
=====================================================================
Dodger7998@xxxxxxx wrote:


I would like to think that rich has already done most of these seeing as

how he has just finished rewiring the whole front of car, but as you
say,
check  anyway


In a message dated 5/7/2009 10:53:53 A.M. Central Daylight Time,
spigot2039@xxxxxxxxxxx writes:


Some other things besides timing to think about, from a page about MP
Electronic  Ignition:

High speed miss

1. Check for loose  connections or poor grounds.

2. Check for dirty or worn  spark plugs.

3. Check for faulty spark plug wires or poor  connections on new wire
sets.

4. Check the battery voltage  at the ballast resistor. It must be no
lower
than 12.5 volts. This is especially important on cars with alternator cutouts or cars with no alternator. If the vehicle uses an alternator
cutout,
teat the voltage with  the alternator turned off.
http://www.geocities.com/MotorCity/1002/ignitconvts1.html

Thanks,
Gary  H.


-----Original Message-----

Rich Kinsley '64 Dodge  Polara 4dr 318poly w/goodies

I did run my car up to about 5200rpm once and it missed a few times.
I'm
wondering if my ECM has been damaged from the previous bad electrical?
Dodger thinks that it  may just be timing. I'll be going back to the
dyno
in a week or two  and I certainly want it right before then!!!!!!!



----
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[Non-text portions of this message have been removed]




Rich Kinsley '64 Dodge Polara 4dr 318poly w/goodies


----
Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks!

'62 to '65 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html.



----
Please address private mail -- mail of interest to only one person -- directly to that person.  I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic.  Thanks!

'62 to '65 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html.













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