G S

Back about 30 years ago I added a tri power on my car. 390/427 Over the years I have lost the original carb now I am looking for the right date code My car was built in Dec 66 what would the date code be? Thanks for any help George

65tripleblack

Carb should be dated prior to engine build date. Within 6 months is acceptable, but about 2 weeks to a month before is best.

Powershift

That should be car build date. Carbs were installed at St Louis.

NCRS allows 6 months, but about 2-6 weeks prior to car build date is the norm.

Larry

Easy Rhino

No dog in this hunt, but how does engine build date, not car final assembly date, tie into engine component manufacturer build date?

Mike67nv

Depends on the component – if the component was installed by the engine plant (manifolds, water pump, etc.), its date should be prior to the engine build date. If the component was installed at St. Louis (carburetor, alternator, etc.), the date code “could” be after engine build date but before final assembly date. With 2-4 weeks being the typical time between a midyear engine assembly date and the car’s final assembly date, the point is moot in most cases.

G S

Thanks but I didn't make my question clear what I need to no is how to decipher the date code? Would a 6 be the year and so on I think one number is the year and one for the month and is one for the day? My car was built 12/16/66 what would a good code be? Thanks George

Powershift

Original Holly carburetors during this time had a 3 digit date code as follows:

First position = year. You want a "6"

Second position = month of the year, with A and B for November and December. You want a "7 or 8 or 9 or 0 or A" in this position. Possibly a "B" could also be used.

Third position = week of the month. You want "1-2-3-4-5" in this position, except if the Second Position above is a "B". Then you will only be able to have a "1 or 2" for that month.

There are instances where the carb was dated just a few days before the car build date. i.e. "just in time delivery".

You do NOT want a four digit date code, since 4 digit codes started around 1972........and also used a different date format.

Larry

R66

R66 was built mid December of 1965. The Holley 3367 is dated 5A4. I guess that is 1965 November 4th week. I believe the carb is original to the car, but you never know.

provette67

Yes the first digit is the year and with your build date you will need one that starts with a 6. From this thread I am guessing that you need a Holley list #3811. Unless your car was from California and came with smog. Either way your search will be a little difficult as these carbs are hard to find.