Q-Jet Date Codes

[bertfam]

70 = Rochester products division and since it's not really needed, some carbs were produced without it.

Ed

[crobjones2]

Begs the question - if 70 is a rochester plant code, why do the Carter manufactured carbs contain the 70?

[bertfam]

Carter was commissioned to produce the Rochester Q-Jet as a secondary source and therefore they would have the same ID markings.

[Boston14]

Here's a picture of my early 69 carb number.  The car is an RS/SS 350 (L48 w/M38) built in Norwood with an 11D (1968) Fisher body date. The carb was manufactured by Carter under license from Rochester. The date is L8 which translates to NOVEMBER 1968. GM parts with stamped date codes do not use the letter i therefore L is for November (L is December for cast parts).

boston14

[IZRSSS]

Boston14,

Our cars were built around the same time and are both L48's. What is your cars build date? Mine is 12A (Van Nuys). Can you also elaborate on your last two sentences...I don't really follow the L part?

[Boston14]

GM parts with date codes applied after manufacture (carbs, alternators, starters, etc.), if they have a date code using letters for the month, are as follows; JAN = A, FEB = B, MAR = C, APR = D, MAY = E, JUN = F, JUL = G, AUG = H, SEP = J, OCT = K, NOV = L, DEC = M.  The letter I is NOT used.  GM parts with the date codes cast in them at manufacture (engine blocks, heads, intake manifolds, etc.), if they have a date codes using letters for the month, are as follows; JAN = A, FEB = B, MAR = C, APR = D, MAY = E, JUN = F, JUL = G, AUG = H, SEP = I, OCT = J, NOV = K, DEC = L.  Hope this helps.  My build date is 11D (Norwood).

boston14

[JohnZ]

Can you also elaborate on your last two sentences...I don't really follow the L part?

It's discussed here:

http://www.camaros.org/forum/index.php?topic=7276.0

[IZRSSS]

Boston14 & John,
You had lost me with the I. Amazing...why the heck would they leave out the I. Makes no sense at all. You'd think they would have found a better way to distinguish between manufacture and post manufacture. Thanks for going to the trouble of printing it out. Now this senseless method makes sense.

Our cars were only days apart on build...cool.

[Mark]

Its an engineering thing.  Letters I's and O's can be confused with numbers 1 and 0, so they are not typically used when using letters to identify components where letters and numbers are used together.

[IZRSSS]

Now it makes perfect sense.

Thanks Mark

[crobjones2]

Here's a picture of my early 69 carb number.  The car is an RS/SS 350 (L48 w/M38) built in Norwood with an 11D (1968) Fisher body date. The carb was manufactured by Carter under license from Rochester. The date is L8 which translates to NOVEMBER 1968. GM parts with stamped date codes do not use the letter i therefore L is for November (L is December for cast parts).

boston14

Looks just like mine ( except yours seems to be a little more golden in color) made E9