cjperformance wrote:Hi, I have had factory tach's give a similar problem, just dissconnect it and try, nothing to loose!
Try dropping plug gap to .030" just to see if you note a difference.
What valve springs do you run,?, your 292ci is going to rpm harder for a given cam/spring combo than say a 350ci will, if the springs are going a little soft they may be giving a little valve float which can give the popping too.
Troy Patterson wrote:Ya, just disconnect the factory tach and see what happens. Some factory tachs require a converter / adapter for everything to work correctly.
If it's not the factory tach, make sure the MSD is grounded properly (I'm sure it is, just got to say it). Otherwise, it's probably something else.
Troy Patterson TMPCarbs.net TMP Carbs
raynorshine wrote:do you have another coil to try? something compatible with the rest of your ignition system?
i chased a high speed misfire years ago, changed the coil and voila! of course, i changed a lot of other parts first
barnym17 wrote:Does your ignition still have the ballast resistor wire feeding the coil?If so when they go bad these are the symptoms, cuts voltage to the coil down to far causing high speed miss.
Winston Wolf wrote:I just went through the same thing. Was using a Mallory Unilite conversion in a stock points distributor, MSD 6AL and blaster 2 coil.
I put in a MSD E-Curve, new coil, and kept the 6AL. Solved the problem (after a plug change too), but I changed it all at the same time. I would consider getting rid of the Mallory for something else. I ran it for 10+ years and the car always seemed to have a miss I couldn't figure out at the strip on hot days. I also do run a factory tach. Coils are cheap, so I would start there. Then maybe spend the money for a new distributor. The E-Curve has a tach output and a rev limiter built in, plus you don't need a MSD box to run it.
Test the voltage from the cars power wire to your distributor and make sure it reads battery voltage. Also might want to run a ground jumper wire from the alternator bracket to the head, on the same bolt as the negative cable on the bracket from the battery.
Brian B wrote:I have also seen this and it was the battery, it had a dead
cell and would start to mis in the higher rpm range..
volts would check good but if you hydro each cell one was
pretty much dead..
Dakota Parts Warehouse
The Ferrea Valve Guy
Ask about our Fast Setting Silicone
877 235 2832
Baprace wrote:I'm leaning towards spark plugs giving you the high speed miss.