Gear placement: 302 ford dimensions from bottom of distributor housing mounting flange to bottom of gear for all 289/302 distributors:   4.031"-4.038"

Gear placement: Y-BLOCK - from bottom of distributor housing mounting flange to bottom of gear for all y-block distributors: 4.991"-4.996"

This measurement can only be taken accurately with the distributor shaft pushed to the bottom and some type of straight edge clamped to the bottom of the distributor gear. Use a high-quality digital caliper.

A 302 distributor (SBF) housing fits the Y-BLOCK without a problem, but the shaft is .958" too short. If an attempt is made, the gear will not fit tightly. The Y-BLOCK shaft can be used to replace the 302 shaft if it is in good shape. The gear must run on the pad in the block with .008"to .012" end play or it will not live very long.

____________________________

The 57-58 Style Distributors like the One I have can be changed as far as the amount of Centrifugal Advance. Greenbird56 has done a lot of  experimentation with Ford Distributors. The Slots that control the amount of Advance can be brazed up to shorten them and filed out to to adjust them. Its a little more trial and error than the later Ones where there are usually 2 different choices on the advance cam. Usually either 10L or 13L which is 20 Advance or 26 Advance at Crankshaft..I like the 57-58 Ones because of the Ball Bearing Advance Plate. I haven't changed anything on the Distributor I have. I just bumped the Initial Timing to 12 because its a stock Engine. Starts fine even Hot which will usually indicate Timing is too much if it has trouble starting.

  

How hard is it to find a good 57-58 distributor?


~DJ~ AKA "Bleach"
1956 Ford Fairlane Town Sedan 30K original miles

With the ball bearing type advance plate? Slim to none, and Slim just left town.

I had to scour the intertubes to scrape up a distributor cam, that cost 50 bucks alone, and I was glad to find it. New weights were $12 per, new shaft $30, gear, bushing $10, $10 etc. The ball bearing plate is about unobtanium near as I can tell.

I have a 1957 ball bearing type distributor.  I plan to change it to a Pertronix unit. I ordered a new vacuum canister from NPD and it came today.  When I installed it, I noticed the advance plate moves without vacuum. I can advance the plate with my finger.  It moves back and forth freely when I put air in it with my mouth.  It's this right?  The original 1957 and the later one is pretty stiff.

Never mind.  I figured out the problem.  I missed some parts.  There is a spring and washers under the vacuum inlet fitting.  Mind fart....

'I have a 1957 ball bearing type distributor.  I plan to change it to a Pertronix unit."

Do you mean just the IGNITOR II module or complete distributor? I don't believe PERTRONIX offers a module kit for the 57/59 ball bearing breaker plate design.

The shim pack/spring you are describing is the early way of calibrating/varying the vacuum advance curve -

____________________________

The Kit from Pertronix fits all 57-74 Distributors. I just installed One in the 57 Distributor I have in mine. Takes the same Points and Condensors from 57 on. Not the same as 54-56 Points. Pertronix 1 (not recommended)/ # 1281, Pertronix 2/ 71281, Pertronix 3/ 91281.

  

The Spacers (the long Tube) controls the amount of Vacuum Advance. The Spring can be shimmed (with the Washers) or changed to control how fast the Vacuum Advance comes in.

  

There is One NOS Ball Bearing Plate on Ebay.  Listing  322869667327. Part # B7A-12151-A or DB-2 newer Part #. There were 2 but I just bought the other One to have on Hand for future use. They do develop flat Spots from moving the same small movement for Years. Mine has flat Spots but by shifting the lower Part it moves like it should. Parts for this type Distributor are going to be even harder to find down the Road so I put Parts and Distributors away if I find good Ones for sale. 

  

"The Kit from Pertronix fits all 57-74 Distributors. I just installed One in the 57 Distributor I have in mine."

I stand corrected. I had read somewhere where that the module interfered with the straight vacuum advance arm on the 57/59 DIST.

My sincere apologizes for not verifying before posting ...

____________________________