anyone understand the date code on these carb.
3878261-eh thats a chevy number
0394 is the date code
getting ready to clean choke horn off if carb is not rare
thank you joe

The part number you cite is for a 1965 Chevelle with big block (396). I believe that it is a factory service replacement, i.e., a carb that was not originally installed on a car from the factory, but one bought over the Chevy parts counter at some later date. I think the “0” that prefaces the date code is an indication of this.

Normally, Holley date codes on engines installed in Chevrolet cars are decoded like this:

First number is year, second number is month, and third number is week of month. The date code on my ’67 Holley (list 3810) is 743, meaning it was manufactured in the third week of April 1967. Hope this helps.

Holley made their great old 3310-1 for the new back then 375hp/396 engine and it and the 3310-2, etc's are great carb's for engines from 302 to 496 or so, imho!! As long as they are tuned for the particular engine/use rpm combination!!

I have a 3310-2 tuned to my mild 496" engine only b/c I am not going to rpm her above 5700 or so..

It was built for grunt. That said, on a 302, it is one high rpm carb!!

pdq67

I have an original run 3310 (a 3310-0 if you will) and I love this thing on my 350. I can tell its one of the first run ones because only the original ones came with secondary metering blocks AND down leg boosters. It had a manual choke though, not a hot air or electric choke, so it was probably not a factory carb off of any car, but an off the shelf part.

This carb is great on my 350 though, its the smoothest-operating carb I've had on this engine, and I've had two Qjets, this 3310 and a 4777 double pumper. It idles smoother than the other three - although I never really discovered why, it accelerates smoother, and it pulls REALLY hard once the engine gets up to around 4500 or so. Its also given me the fastest and most consistent ETs of the two Holleys, even though I have a manual trans car. Never tried the Qjet at the track though.

Its a great carb, I love it :)