Correct distributor vacuum advance unit for a 390 GT

Cougar Community Classic Cougar Maintenance Restoration and Repair
1

Hi everyone,

I am need help in determining the proper distributor vacuum advance unit that should be on a 1968 XR7 390 GT (S Code) that is a CA DSO with an automatic transmission and a/c. Is the dual advance unit correct since this setup is more emissions friendly? I see examples of both single and dual units on the internet but I think CA is always the exception.

I am trying to stay as close to concours as possible so I will be using the C8OF-12127-D distributor.

Thanks,

Steve

2

You want the dual advance for a '68 390 4V with automatic.

3

Thanks for the quick response. That’s what I suspected was the answer.

Steve

4

Dual advance is the simple answer.

There is a shopping list of marked dual advance units. So far I have found A12, B12, C12, & G12.

The A12 was found on a C9OF-Z distributor which is for a 1969 351-4V with FMX.

There are also at least two versions of them too.

HP6 would be for 1968-69 428CJ with 4 speed.
X6 would be for 1970 428CJ.

5

so is the dual advance for all 390 gt s codes w/ automatics

6

All 50 states 1968 “S” code 390GT, if it had automatic transmission it had dual advance. Also Thermactor smog system was standard.

7

Isn’t the one on the left the later (after 70 version) ?

8

I have no idea. Is that gospel?

9

Checked everything I have and that’s the pattern I’m seeing. Feel pretty comfortable with the statement at this point. Allot of the ones I see 9left version) have a large AUTOLITE stamped/cast into the square surface. likely at least on the 71-72 originals

10

Yes, Autolite cast. I would have guessed ‘Motorcraft’ like is stamped on distributors and carburetors for the later parts.