Re: 1967 Z28 Fan
 

A lot of fans have the H and FRONT stamped on them. I think the H may be a manufacturers mark. The 3" bolt pattern fan is a popular fan used throughout the Chevrolet lineup. The base of the clutch usually has a date stamped on it. Check yours, its probably a late 60's date.
The above fan is the 67 z/28 fan and has those same markings, but the bolt pattern is 3.25 inches and 4 rivets per blade. I have seen 3" bolt pattern fans same as yours with 5 rivets. That style seems to be later like 1970 and on.

Re: 1967 Z28 Fan
 

I believe the fan Dan has was used on lower performance applications in the mid 60s like a 63 or 64 327/300hp, etc.

Jason

Re: 1967 Z28 Fan
 

I think it's an RPO K02 fan that could even have been ordered on a 327 2-bbl, if desired.

Re: 1967 Z28 Fan
 

The 3" 5 blade 4 rivet fans were used on all cars with K02 and also any SB or BB car that had air conditioning. I believe the 5 rivet blade was used 1965 and earlier, and I can't recall ever seeing a 66 or later car that didn't have a 4 rivet. They are pretty common. I have sold decent units in the past for $100-150.

Re: 1967 Z28 Fan
 

I believe the 'H' was for the manufacturer, Hayes-Albion.
Excellent article on fans and clutches at CRG here: http://www.camaros.org/coolingsystems.shtml#fan