Does anyone have any experience with an engine missing under load? my 81 misses at about 1500-1800 rpm in second and third gear. the plugs (correct gap) new MSD wires and coil,cap and rotor. I am trying to fix this problem by thursday so that i can make the trip to carlisle ( i dont want to have to get a baby sitter)

run 2 cans of good injector cleaner, usually a miss under load is plugs or wire cross firing but you have new wires just make sure they havent hit a manifold and melted.. also look for carbon tracks on the inside of the dist.cap. give it a good cleaning as this will also cause a miss. i have run bosch platinum plugs in all my cars for 15 years and they are good for 100,000 miles

the cap is new and i have pulled the wires and have checked them for burn marks -nothing there either. thanks for the feedback.

Sounds more like a fuel problem to me. If the wires, plugs and cap/rotor are good...

i have changed the fuel filter at the carb.

a buddy of mine sugjested changing the carb to an earlier carb. and get rid of all of the emission sht then change the distributor and get rid of the air pump.

even with he carb and air pump it still shouldn't miss
you could try another carb from another car just to see if your carb needs rebuilding

Just for laughs,pull the dist cap off and the rotor,check to make sure the centrifugal advance is working.my 78 was doing the same thing come to find out it wasn't advancing right because there was rust and gunk on the collar and the shaft that kept the advance assembly from moving back and forth on the shaft.take off the weights and springs make sure that collar can move easily on the shaft so the weights can move and swing in & out the way their supposed to.a lot of wd40 and patients I did it without removing the dist.from the car just make sure you dont drop the screws or springs down in or you'll be pulling it out

also check the vacuum advance, put a long hose on the vacuum advance diaphram and suck a little on the hose, you should see the dist. advance and return back when the pressure is let off,

If you still have the stock dist. & carb they are controlled by the computer (ECM). '81 was the 1st year for "CCC" engine management system.
So, there will be no vacuum advance and no weights. It has a 4 wire EST. (Electronic Spark Timing) module in the Dist.
The carb is an Electronic Feedback type.
Try this...open hood, remove air cleaner housing, reach in the car and turn the key to on and listen for a rapid clicking noise from the carb. If you hear nothing then chances are the MC(Metering Control)Solenoid is dead. This controls the position of the primary metering rods in the carb. If the metering rods aren't moving according to engine speed this may pose a problem.
Let us know what you find out.
Sarge