I need a light bulb moment here as I'm running out of ideas.

About 5 months ago I purchased a '61 Lincoln that supposedly had 33k on the clock. I had never driven a MEL powered car before so wasn't sure if the slow nature of the car was normal. I knew something wasnt' right when I couldn't get to 65 mph on freeway. So I ran a block test and failed. Also found oil in the coolant.

So $5,600 later I have a newly rebuilt engine, but STILL NO POWER. Supposedly done to correct compression ratio (stepped pistions). I can get to 70 mph if I keep my foot on the floor. Choke is working and throttle plates open up all the way.

This is what I've tried so far:
1. Rebuilt carburator (2bbl Motorcraft).
2. Replaced exhaust system (thinking old exhaust could have collapsed inside)

On the Lincoln forums they tell me to check the timing advance...which I've never done before. I don't even know how, but was going to play with my timing light tonight. The guy who put my engine back together builds racing engines so I assume he set the timing correctly.

Some other thoughts...possibilties?
1. Power steering pump is bad on this car. Well it works, but it whines loudly and leaks. It's on the crank. Maybe it's robbing power? I plan on rebuilding it in a month or so (after I recover financially).
2. I replaced my points with Pertronix ignitor and Flamethrower coil, but damn if it doesn't feel like this engine is not running on all 8 cylinders. It runs smooth though.
3. Friction in the brake system. My car pulls to the right and vibrates on the freeway. Perhaps one of my brake shoes is dragging? I'm putting it on a lift today to find out.

Those all sound like good things to look at. I doubt the power steering pump would rob that much power.
What about the transmission, could it be slipping? Or not going through all the gears? I had that problem on my '59.

The transmission feels correct, but without a tachometer I can't say positively. All I know is at 60 mph my foot is at about 80%. If I go ahead and put it all the way to the floor the transimission will downshift and I will slowly accelerate up to 65 mph and it will upshift and start to slow down again. It's a vicious cycle...especially if there is any up grade in the freeway.

Check your fuel supply to the carb, if you haven't already done so . Check for volume with a hose attached to the fuel line dumping into a container,being careful not to spill. If that checks out, pop the distributor cap . Their are two advances ,a centrifugal which you can preliminary check by seeing if the upper portion of the distributor shaft will rotate slightly by turning the rotor ,and spring back on its own,separate from the lower portion that is driven by the camshaft, if it sticks it won't work. The other part is a vacuum advance which you can check by hooking up a hand vacuum pump , or you can provide the vacuum with your own mouth and a length of clean hose,while observing the point plate in the distributor. It should rotate or pivot a few degrees .If you can't build any vacuum, the advance will need to be replaced. If you build vacuum but it doesn't move, the plate may be stuck or the advance may be at fault . Low output ignition coils can also limit power, but usually are affected by temperature and get worse the longer it is running.

This is excellent advice and exactly what I needed to understand the advance system. I will check this out tonight.

Vacuum diaphragm didn't hold pressure. I put a new one on and also corrected my timing.

Much better, but not 100% yet. Thinking I still have some old gas in my tank so on next fill up with 91 I'm crossing my fingers.

I'm 99% sure I've found the main culprit...the previous owner had put a Motorcraft 2100 carb only rated at 300 cfm. This is supposed to be on a 289 Ford...not a 430. I have a rebuilt Holley 4412 that I'm putting an electric choke on tonight and I'm pretty sure I'll have the power I was looking for. Will update.

Any updates? I'd like to hear how this turned out.