[unruhjonny]

I'm venturing outside of the normal sub-forum, because I hope to get max exposure on this from membership.

I have been a "details guy", and since I first lost the chrome filler cap I got with my car back in 1997(?), I have kept my eye open for these... and I don't come by them often.

These are the three that I have right now, and the different one, is my most recent acquisition.

Can anyone tell me what these are period correct for?



I have understood that there are several different chrome filler caps, some are correct for Pontiac's of certain years, others are more or less generic GM replacements...

Thank in advance for any assistance that can be offered.

[OG68]

This was chrome at one time. Original cap from my 68 GTO. Arrows point to the AC logo. Three weld spots on the back side.

[unruhjonny]

Ok - thanks!
So that's like the two I have pictured on the left, is that correct?

[OG68]

I would say so.

The Ames catalog breaks it down as follows;
AC Logo - 67 California cars, 68 - 69 all
AC F65 - 70-71 RA cars, 71 painted
That being said, that is based upon what Ames has observed.

I wonder if the original AC logo is consistently oriented as shown.
I noticed with the reproduction I have, its turned 90*.

[GT182]

Don't use any that say 710 on them.

[unruhjonny]

so what's not mentioned in that Ames quote is that before 1971 chrome dress up (valve covers and air cleaner lid) were a part of the GTO, Firebird 400 & Formula 400 package.
I do not know if the GP had the same chrome package standard.

After 1970 the chrome package was relegated to an over the counter parts kit - untill the 77-79 W72 package was released - which included chrome valve covers (but not the same nice shiney ones as before).

When ever chrome valve covers were included, or sold as a package, a chrome cap would have been included.

As I see it there could be variants of:
- The parts included with the vehicles prior to 1971
- The over the counter kit(s)
- the W72 engine bits

[JimFB400HO]

Like two you have, my original '68 Firebird 400HO:

[77 Canamman]

1977-79 W72 also used the same FC-65 chrome cap as the earlier '70's did.

[unruhjonny]

/\ thanks!

[60sstuff]

From decades of collecting early Survivor GTO’s and their factory parts.

Below samples have come from 1964 - 1967.

First 5 pics are 1964.

‘64 closed cap (Top Hat) with option 614
‘64 open breather cap with smooth rim (no crimps) and trapezoid openings.

[60sstuff]

The first usage of the flat sealed cap with AC and three spot welds was installed on a 1965 with the 614 option.

This cap was again used in ‘67 with the A.I.R. and 68-69, but not 1966.

Last photo shows the one year only ‘66 cap with hose attachment for the 614 / 616 option.

[60sstuff]

The 49 state open oil fill cap used in 1965 - 1967 used the twist in style that was crimped on the lip and had round breather holes.

Last photo is a ‘67 A.I.R. equipped with the correct flat closed AC cap.

[Goatracer1]

The last photo 60sstuff showed is the same cap used on my 1962 Bonneville with California emissions system if anyone cares.

[Joe's Garage]

Now we know where the Pontiac engineers got the caps for the prototype SD455 engines. Off the shelf in the parts room!

[unruhjonny]

Wow!

Thanks everyone who helped me clear this up!

So If I have it straight the AC-triple-tiny-spot-weld caps I have are 1969 & earlier, and the FC-65 is 1970 & later - is this correct?

[Goatracer1]

Joe's garage's picture is the same as my 1962's fill cap with the same hose. Been around for awhile.