Thread: Low RPM miss

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I have an 89 camaro with a professionally built 383 stroker. Everything under the hood is new, I mean everything!
I recently changed out the Holley 750 secondary vacuum carb over to a 750 Holley mechanical double pumper and went up 2 sizes on the primary jets. Huge increase in power!!
I also set timing at 33 degrees at 3000rpm according to the builder's advice.
I also changed the ignition module to a Mallory Hyfire 6al. (The distributor is an HEI Mallory).
Since changing these three things I get a low RPM miss, up to around 1600 rpm's, that seems to get worse the longer I drive. Also, my plugs are almost blue in color and i'm assuming this is running much to hot or lean. (Accel shorty header plugs)
Which of these three changes should I look at first and what can I do to correct the problem.
I was told that a low RPM miss is electrical and a high RPM miss is fuel. True?
I contacted Mallory tech and they told me to check all grounds in the ignition module and braid all the wires together, change plugs to standard non resistors and make sure I have solid core plug wires. Did all this and it didn't make a difference.
Any suggestions or past experiences with this problem? I'm afraid of burning a hole in a piston or something.
Thanks

sounds to me like a vacume leak. start it up (I'm assuming it misses at Idle ?)
Take your a hand held propane torch turn the gas valve on (don't light it)
and hold it over top of the carb and see if it smooths out. If it does you have a vacume leak somewhere or you are extremely lean....