I just changed the clutch on my 83, and after getting it all put back together it has an intermittent loss of power. I took it out for a test drive, and after it warmed up, I could stomp on the accelerator and the RPMs would barely go up. When it was doing this, the sound of the engine changed...it sounded a lot lower in pitch. I'm thinkin, what the hell and it would suddenly go back to normal. It seems like it would start at 4500 RPM but was intermittent. I have checked the plugs, not fouled. The vaccum lines seem to be OK, and the car would do the same with the air cleaner removed in the driveway.

Any Ideas?

 

I should also mention that the 7 would backfire while demonstrating the loss of power, and the low pitched engine noise.

 

I should also mention that the 7 would backfire while demonstrating the loss of power, and the low pitched engine noise.

 

Maybe your secondaries are not opening up, and its ******* out!