I had the 57’s distributor centrifugal curve changed. It now starts at 1550 rpm and is all in at 2500 rpm (22 degrees). Hopefully this is close to optimal.

Glad to hear the Load O Matic is working correctly.  As far as the 57 strib, if it is still set to start advancing at 2100, I think you may have somewhat of what you had with the bad vacuum canister on your LOM. That is, no advance until 2100. With no advance until 2100, I would think the manifold vacuum will be very low under load with retarded timing while trying to gain speed. Just my thoughts................

64F100 57FAIRLANE500

Installed the replacement VC yesterday. Completely transformed the car. The engine now accelerates smoothly and cruses at freeway speeds with steady vigor. The coolant temperature gauge hovers one click above the centerline instead of being dead-pegged against the H stop. Couldn't be happier!

Or could I? Now I'm left wondering whether I should proceed with swapping this working 2140 Teapot carb+matching distributer combination (VC only) for the '57 Dizzy (VC & centrifugal) + 500cfm Edelbrock AVS2. How much better will the engine perform in terms of power and efficiency with the latter? Only one way to find out huh? Here we go!

Anyone have thoughts on how this will turn out? Will newer combination make a noticeable improvement or just be gilding the lily?

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A great Thanksgiving to you and every one else here..........      Good luck, we'll be watching.

64F100 57FAIRLANE500

Great article, thank you!

I'll bump this thread with the initial results once I have the 317ci Lincoln back on the road with a new VC (next week).

The VC I finally found is P/N B5S 12370-A

Meanwhile, Happy Thanksgiving!

What you have had done may well be OK. If the guy had a DIST MACHINE he had to have basic knowledge.

You will not know for certain until you plug it in and fire it. If she rattles (under load), back initial off. If she keeps rattling, you will have to most likely re-curve.

There are curves for a stock application, a warmed up engine, hot street, hot street/strip and full competition. You have to know what you have and where you want to go. And don't forget the DUAL ADVANCE DIST vacuum advance canister is adjustable also.

Here is a BASIC TECH ARTICLE that may help explain -
- https://www.fordmuscle.com/archives/2000/03/timing/index.php

You have a 317 (?) dragging a heavy car with limited carburetion CFM and engine breathing caoacity.

Best of luck to you and the LINCOLN.

All of the above is IMO. Your mileage may vary.

____________________________

I reside in CA. There's a big welcome sign on Interstate 80 when entering Northern CA . It declares:

    Welcome to California
The Land of Fruits and Nuts      

Humm, back to Ys. All of the numbers I've listed are indeed crankshaft degrees (multiply cam degrees by 2). I asked the man who rebuilt my '57 dizzy to change the original centrifugal spring for a "new and slightly stiffer" one. Upon testing it on his old Sun machine the new spring turned out to be heck-bunch stiffer. It doesn't budge one click until 2,100 rpm. So you did read the numbers correctly. We briefly deliberated replacing the spring right away but my curiosity got in the way and I volunteered stab it in "as-is" and see what happens (besides wrenching my back playing dizzy inny-outty). There's also a chance the Sun machine's instrumentation was off. Best case outcome ----only my back goes out. Worse case - I must reach into my back pocket for another hour of labor while my back is out.              

It still appears we're mixing distributor specs with crank specs.  The above posted specs are in distributor degrees and rpm's. Just double those figures and that will be what you will get at the carankshaf. The B7A-12127-D spec states the advance starts 1* at 450 rpm. Therefore, at 900 engine rpm's there should be 2* advance at the crankshaft and this is typical.  But when you say "begins at 2100rpm" is not logical.    As far as 42-44* while cruising and not detonating may require gaining some experience with your setup. There are many variables that come into this equasion.   Maybe I missed it but where about are you located?  

64F100 57FAIRLANE500

Your comments make sense and thanks for including the detailed data specs.

The spec states centrifugal all in by 2000 rpm. So mine is way off then. Unfortunately I didn't get a curve ---the mechanic gave me a few data points he wrote down ---Begins at 2100rpm, all in 22 degrees/4,400rpm, 10 degrees/ 2800rpm, 18 degrees/3600. At least I can extrapolate the curve.

Since this car will primarily frequent freeways at 2800 rpm, my total timing should hopefully be 12 initial  + 14 vacuum + 10 centrifugal = 36 degrees. I suspected this new curve would not be optimal but decided to roll with it and see what happened (yes it's my first Y block rodeo). From what I'm reading above I'll leave a lot of performance on the table and money at CA tax (gas?) pumps.  

How much advance can a 317 accept when cruising at light load? For lean fuel economy can it take 42-44 degrees without detonating?