Another finding.

The transmission in the El Camino has always shifted OK but not right. I have tweaked the modulator now and then with scant results. When the temps got lower the trans. really got finicky. Shifting at 2200 rpm and higher when warmed up. I tweaked and tweaked and it shifted higher no matter which way I turned the screw in the modulator. I know it's hooked up right, I got full manifold vacuum to the original metal pipe. I called Richard and he suggested getting a new modulator and to be sure there was enough vacuum. What does he know. I looked on line and the site said no or low vacuum signal causes late hard shifts. Sounds like my problem. I pulled the hose connector off the manifold and tried to blow through it, I removed the hose from the modulator. The metal pipe is plugged or bent closed somehow. I took the pipe off the engine and in the end at the manifold a mud daubber had filled the pipe with mud. The opening is necked down to 1/16" dia., must have been a midget bug. I cleaned the pipe, washed it out and replaced it on the engine with new hose ends. Shifts great now. The rubber connector at the modulator was the one that was on the car when I got it and was cracked badly to boot. But with no vacuum getting through it didn't matter. All good connectors now.