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Discussion Starter · #1 ·
My car has a miss at about 6000 rpm. It has a msd 6al box, and a dual point Accel dizzy. The points are less than 1000 miles old. The car is really running good right now up to the 6k mark. I don't really want to start the quessing game and make a lot of changes to it. So how do I determine what is wrong and why it is missing at the higher rpm's. Should I replace the points, I believe the timing is correct and the dizzy has been set to bring in 38 degrees of timing.
 

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I'd look for a dyno tune place and 'scope it - There are numerous possibilities and there's no sense trying to replace parts until you find the problem. Possibilities are:

Point bounce
ignition wires
rotor cap leakage or cross-tracking
lean A/F ratio at high RPM's
valve bounce (from weak springs)
sticky valves - not seen too often these days
plug gap too loose

There are others too -
 

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To add to cosmo's helpful list, it could be something as simple as "less than perfect" points, or dwell setting. Those points must be in perfect shape and setting for high RPM operation. I would inspect them, file down as needed, and use a dwell meter to set.
 

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Which RPM pill do you have in your MSD box? You might be hitting the rev limiter. My MSD box came with the 6000 RPM pill installed.
 

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Discussion Starter · #6 ·
If I remember correctly, I am using the 6800 rpm chip. I know I have had up to 6500 rpm without any problems before.
 
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