Also, I had my door open while recording the engine hot video and the interior lights were flickering with the fluctuating voltage.

 

Hook your volt meter to the ign terminal in the fuse box.

 

I do not see a terminal labeled "ignition" on my fuse box. Which one is it?

 

Never mind, brain fart. If that is where your meter is connected and its fluctuating you may have a voltage regulator going south. Unrelated but I would also clean all those fuse holder contacts.

 

So I gave up and sought professional help. I took it to Thornton Auto (10 mins away). It turned out to be excessive heat. I installed the gauge set with the intake swap. At idle, the temp was climbing up to as high as 230 deg. He installed a 7 bladed fan, new clutch, and a fan shroud (modified '70). It gets no higher than 185 now and the stumble is gone. The simplest things...I don't feel too bad because he said he would done all the things I did.

Thanks to everyone for the help.

-Tim

 

Great that you have it all figured out. Heat is the enemy to almost everything automotive.

 

Great to have guys who know Olds so well, so close. Yeah 230 was probably boiling the fuel and causing a lean stumble. Glad it is fixed.