just curiuos if there are any real differences as far as performance goes between a rochester quadra jet from a big block olds in 1970 as opposed to a 1976 big block olds? .assuming both are stock .

 

Yeah. The 1976 carb will have leaner jetting and more "features" to operate emissions equipment like EGR. Certainly you can change the jets and rods in the later carb to match the early one, however.

 

Sounds good thanks joe

 

and the 76 will be an 800cfm more than likely

 

The later carb will have the better sealing main well plugs, adjuatable part throttle, and more than likely the better needle and seat setup. Once you make the necessary calibration changes it will work just as weel or better than the factory carb.

 

i finally dug out the old quadra jet from my 1970 455 .but i ran the numbers and it came out as a 1973 350 carb .can someone double check for me?carb number is 7043250 ra .im sure it could have been replaced years ago

 

You are correct, 73 Olds 350.

 

FYI, the third digit is the decade (2 = 1960s, 4 = 1970s) and the fourth digit is the year (43 = 1973).

 

Great thanks for the help guys