flathead 53
Well-known member
Changed my 53 f-100 to twelve volts , also bought A pertronix distributor. , with the new distributor will the vacuum line go to the carb like the loadamatic, or to manifold vacuum? thank you
pertronix distributor
- Thread starter flathead 53
- Start date
cadillac512
Well-known member
Were there instructions? If not, what's the part number of the distributor you bought?
19Fordy
Well-known member
paul2748
Well-known member
The stock 53 carb vacuum source will not work with the Pertronix. The stock vacuum is very low while the Pertronic will require a stronger vacuum "pull" and is usually connected to a source below the throttle plates.
Manifold vacuum is really not the proper source for distributor vacuum but I have heard of others using it. I think it must be metered.
Best is to not use the vacuum advance. You can run w/o it although you may notice a small decrease in fuel economy
Call Pertronix and discuss it with them
Manifold vacuum is really not the proper source for distributor vacuum but I have heard of others using it. I think it must be metered.
Best is to not use the vacuum advance. You can run w/o it although you may notice a small decrease in fuel economy
Call Pertronix and discuss it with them
petehoovie
Well-known member
Gene1949
Well-known member
absolutely use manifold vacuum. Much improved cooling at low/cruising speeds and drivability at any speed. And yes a measurable increase in fuel mileage. Every manufacturer used a vacuum advance of some sort before the advent of computers.
My curve;
total Mechanical including initial: 16 degrees at 1800 RPM. max 22 degrees at 2300rpms. Credit due to one of the wiser heads here (Gramps I think) who developed this curve after much testing
vacuum: 14 degrees @ 15". I used the vacuum level at 70 mph as a setpoint. You may have to change that a bit as that works with my car at this elevation.
My curve;
total Mechanical including initial: 16 degrees at 1800 RPM. max 22 degrees at 2300rpms. Credit due to one of the wiser heads here (Gramps I think) who developed this curve after much testing
vacuum: 14 degrees @ 15". I used the vacuum level at 70 mph as a setpoint. You may have to change that a bit as that works with my car at this elevation.
Ol' Ron
Well-known member
Gene has it. The ignition system is governed by the engine load, and thus the "load a matic"/ his systen uses a special carb to supply the vacuum signel to the distributor and works well on a STOCK engine
The vast majority of the engine manufactures use the vacuum from the engine t determine the "advance curve". The advance curve provides the proper amount of ignition timing to the engine under ALL driving conditions. Such as puling aload up a hile or fuel mileage when crusing down the interstate.
When you modify an engine YOU have to consider what this curve must look like and is dun when TUNING the engine. This requires Knowledge as well as a AF metter for the carb and a timing light with a degree wheel on the crank ( apiece of tape with numbers onit). Starting with the factory numbers you can make adjustments for power and economy. And this requires Knowledge.
Gramps
The vast majority of the engine manufactures use the vacuum from the engine t determine the "advance curve". The advance curve provides the proper amount of ignition timing to the engine under ALL driving conditions. Such as puling aload up a hile or fuel mileage when crusing down the interstate.
When you modify an engine YOU have to consider what this curve must look like and is dun when TUNING the engine. This requires Knowledge as well as a AF metter for the carb and a timing light with a degree wheel on the crank ( apiece of tape with numbers onit). Starting with the factory numbers you can make adjustments for power and economy. And this requires Knowledge.
Gramps