OK, now i'm baffled - high RPM miss???

[Craig -1965]

High RPM miss

Barry,

Don't forget distributor cap and rotor, cracked distributors do strange things.

Regarding the dislike of electronic ignition, there is a reason all car in the last 15 years are electronic, just think how many times the old points are bouncing around at 6000 RPM's.... on a V-8 that's like 48,000 times

good luck

 

[BarryK]

craig

I put on a new cap and rotor in Jan with all the other engine work. I still had doubt with them so even swapped back to my old known good ones.

sorry, you can't compare the modern electronic computer controlled ignition systems to a simple electronic conversion kit for an older points distributor. That comparing a slingshot to a modern ballistic missle!

 

[Craig -1965]

High RPM miss

Hello Barry,

The only point I'm making is; there are currently 3 way to signal the coil to fire the spark plugs.
1. Is a set contacts that are opened and closed by the means of a phenolic block rubbing against an octagonal cam wheel. The contacts are spring loaded to return the contacts to the original position. (point bounce)
2. A light beam that is parted by means of a perforated wheel, thus signaling the coil to fire the spark plugs.
3. A 8 finger spoke shaft that rotates next to a fixed magnet, thus signaling the coil when to fire the spark plug.

Doesn't seam like rocket science.

I'll be really interested in seeing the root cause of your engine miss.

Good luck....

 

[BarryK]

Craig

see the thread I started yesterday.
it's called "Update on high rpm miss"
It WAS the resistor plugs. As soon as I swapped them out for non-resistor plugs the missing stopped.

 

[Craig -1965]

Engine RPM miss

Hello Barry,

Well now that is interesting, good thing I'm not in LasVegas, would have lost my ass.......... Guess resistor plugs have "resistance".

Have a good one Barry....
:W

 

[Ken Anderson]

Hi speed miss = AC spark plugs, especially R's (plug reading means nothing with these plugs). Also run 44's in the summer & 45's in the winter!
+ add in carbon thread wires and a 40 year old coil, or one of the new GM "replacements" and you're lucky to hit 5 grand. Good luck!

As I said!

 

[JohnZ]

There are lots of variables at work here that need to be considered - my original/stock '69 Z/28 with its (blueprinted) original Delco 480 distributor and Accel 28-32 oz. points, stock-type carbon-core plug wires, stock coil, and R45S plugs will howl to 7000 without complaint or miss any time I nail it, and hasn't had a miss or a fouled plug since I switched from 44's to 45's many years ago. I spend $12.00 once a year for a fresh set of plugs, and don't touch it otherwise other than checking dwell and timing.

 

[BarryK]

John

until a few weeks ago I could always take my car up to redline without a miss either.
Stock distrib, stock coil, heavy duty points, AC R45 plugs and she always ran fine.

over the winter I swapped out from stock (or stock type) wires to the Delco 508N wires, put in new R45 plugs, rebuilt distrib, new distr cap and rotor, rebuilt carb.
Sometime from when I got her running again in the winter until a few weeks ago she developed this miss problem. I honestly don't know the answer WHY the non-resistor plugs worked. Maybe it was my friends theory on the resistor in the plugs with a higher suppression wire causing a voltage drop? maybe it was something completely different? I don't pretend to know the real answer.
all I know is that after putting in the non-resistor plugs the miss went away.
It would be nice to know for sure what the answer is, but for now at least I'm just happy the car runs much better

 

[vnv bro]

Barry:

This may sound wild but the problem might have been the gas. This is about the time the oil companies switch from winter blend to summer blend. So its possible the problem was the winter blend of gas

 

[BarryK]

Hey Mort!

yep, considered that. Went thru two tanks and than I even put in some CAM2 racing fuel while I was at the track last weekend and it made no difference.

I understand you are going to be at Carlisle again this year. Look forward to seeing you again.
Maybe you can keep your little brother in line and behaving........

 

[G Winter]

Barry,
You didn't say if you got as far as changing the coil. If you didn't don't be surprised if that high speed miss comes back. You just might have a coil going south on you. That could be the reason(along with the wires) that the Resistor plugs gave you problems. I wouldn't totally discount the condensor.

Glenn

 

[BarryK]

Glen

been raining off and on the last couple of days here so haven't had much of a chance to drive her more since my test run after the plug swap but I'll be keeping an eye on her during the next number of drives.
IF the miss strats to re-occur the coil is actually the next item on the list to try. A friend already lent me a spare he has that is a known "good" one in case I need it to try.