My 1980 Caballero Diablo has a very bad miss under acceleration. Idleing is only very slightly rougher that the engine used to be.

The engine is a 350 SBC with Edelbrock Performer cam and intake, Holley 670 Street Avenger, Flowtech Headers, Mallory HyFire VI-A Ignition Box with a Mallory Promaster Coil. I use the stock HEI magnetic trigger still in the OEM distributor body. The Ignition was installed about four months ago. The carb is about five weeks old. The car ran great until the Miss started about a week or so ago.

I thought that miss was caused by an ignition fault. So I changed the plugs, Cap, and rotor. I cleaned all of the connectors for the Ignition box to make sure that the the HyFire was powered ok. I checked the initial timing and it is set at about 10 degrees BTDC as before when the engine ran well. The plug wires are Accel 8mm and seem to be ok.

I have breifly looked at the carb, the float level for both bowls is about 3/4 up the sight glasses, the carb stud bolts are tight and the electric choke opens properly.

I am thinking that I have blown a power valve or dirt in the secondary bowl or bad fuel pump that cant keep up?

Any suggestions about anything that I am forgeting?

My guess is the wires. Can you isolate the miss to a particular cylinder? If so switch wires with another plug & see if your miss moves to that cylinder.

7d8ss...

I took the carb off and dissassembled the bowls and plates. I found a nice gob of a brownish jelly like goop on the power valve. I think that it is a blob of dried gas from a used fuel pump :oops: that I took off the shelf and installed about a week before the new carb was installed.

I used up a full can of carb cleaner flushing the bowls, venturies fuel passages etc. I removed and reinstalled the jets both primary {#65} and secondary {#68} and replaced the power valve {6.5"Hg.}.

The car runs way better when idleing but under moderate aceleration, the sputtering is still there a bit. I changed the brass Holley filters in both inlets and will buy and install a third filter inline downstream from the fuel pump.

I also poured a bottle of Carb-Medic fuel system cleaner into the gas tank.

I can only wait and see if the Carb-Medic does anything to clear this up. If it does not totally clear up, I may have to tear down the carb again and soak in a carb cleaner.

gilc