I have a 71 Chevelle Heavy Chevy. 9.5:1 454 bored .030 with a street cam. Mighty Demon 850, Edlebrock Air gap Dual plane, and MSD 6AL with the pro-billit Dist. Now the problem: The driver side is miss-firing. i have straight pipes that are separated so i know it is the driver side. I have adjusted the valves, RE-Jetted the carb, Changed the carb, Reset the idle mixture screws, changed the sp. plugs, checked the firing order, checked compression, tested spark plug wire resistance (they are new wires), and pulled the plug wires one-by-one which didnt change the idle. All the cylinders are firing at some point but not at idle, because all the plugs are being burned. I dont know where to turn! Help Please! any Ideas?

Try and borrow somebodies infrared digital thermometer (gun with lazer) and point it at each header tube. The one that runs colder than the others at idle is your culpret. Then start by changing that spark plug wire with another to see if it changes (Ive had a new set of wires with a bad one). If that doesnt work, change that plug, relash that valve etc...

You can also use a spray bottle full of water to check which header/cylinder is not firing. The water should boil off the header pretty quickly when firing correctly.

I always wanted an infared thermometer.

Mis at idle only?,Take a comp test to make sure you dont have a valve or 2 adj a smidge too tight,that can cause a mis at idle that smoothes out smoewhat above idle.

Also,you could have dirt in the idle circut of carb.

Possibly one of the plug wires is arking off to a header or somewhere else,fire it up at night and pop the hood and see if any wires are arcing to headers,block,v/cover,etc.

Bad/bent valve?

Broken/weak valve spring?

Vacuum leak at carb or intake (Cracked intake?) leaning out idle enough to misfire?

If holley type carb:

Warped or cracked metering block?

Bad metering block gasket?

Clogged idle air bleeds?

These are just a few things that can cause a misfire at idle that could possibly smooth out some as rpms rise above idle.

Scott

You can also use a spray bottle full of water to check which header/cylinder is not firing. The water should boil off the header pretty quickly when firing correctly.

I always wanted an infared thermometer.
Got mine for $60 from Summit.Hand held and up to 990F.Great tuning tool.I quickly found a relay in an (inconveniance center) that caused a parasitic draw on the battery.Works on beer cans also.lol.:beers: