409 dual carbs

[Harry Vanderveen]

Moving along with the with my 409 (1965) build and making sure that what we have for parts is correct, the dual carb set up that came with has the following carb #s 9605S & 9635SA these are the compition series carbs. The build is a stock 65 400HP , going to maintain the same specs for the internals, wanting to verify thet these are the right replacemwent carbs for the original 425HP design. Sorry if this question has been asked a thousand times but my search in the forms did not come up with anything. thanks in advance

 

[La Hot Rods]

The 9605s is a 600 CFM and the 9635sa is a 625 CFM.
I run a pair of 625 CFM on the race car.
What are your plans for an air breather? These carburetors will have a larger air horn than the factory AFBs would have.

 

[63impalass409]

If your building a 65 400hp motor for a 65 the factory never put dual carbs on in 65 but nothing wrong if someone wanted to. My 65 impala convertible is a replica of a 400hp as it would have come frome the factory with a 65 nos fitted block 583 heads 65 aluminum intake and carb and so on only thing I did incorrect was add a factory cruise control as that wasn't possible to get on a 400hp motor.

 

[Harry Vanderveen]

likely going with the Edlebrock open filter

 

[Harry Vanderveen]

If your building a 65 400hp motor for a 65 the factory never put dual carbs on in 65 but nothing wrong if someone wanted to. My 65 impala convertible is a replica of a 400hp as it would have come frome the factory with a 65 nos fitted block 583 heads 65 aluminum intake and carb and so on only thing I did incorrect was add a factory cruise control as that wasn't possible to get on a 400hp motor.

yes i realize the 65 was a single 4BBl but i am keeping the dual quad set up, all other components of the internals will be maintained. thanks

 

[Harry Vanderveen]

3361S Front, 3804 Rear carter afb, from the resource page, are these carb numbers i have a replacement for the originals (500 cfm carbs?) and does it make sense that the carbs are 600 & 625 CFM ? both carbs are in decent shape the front carb looks like new (apparently it was hardly ever opened up ? )

 

[pvs409]

correct 409 2-4 barrel Carter AFB carbs for 1962- 1964 are Carter AFB #3361(front) and Carter AFB #3362 rear and Carter AFB 3804 (GM replacment rear carb ).
These factory Carter AFB 409 carbs are around 500 CFM carbs.
use of the 600 CFM and 625 CFM carbs you mention depend on what was done the engine (compression ratio -factory 409's with 380 HP (1962) and 400 HP (1963-1965)motors was 11 to 1 with solid lifters (this compression will not normally run on todays non premium gas requiring racing gas to aviod pinging),
All my 409's were built with 10.5 or less compression to be able to run them on Unleaded pump gas -My 409 stroker motor has 10/1 to 10/5 compression is 530 HP )
What cubic inches are you running (bored out motor or stroker motor ) and what head work was done to increase flow(do you have the high horsepower 583 heads on your 65 motor?)
Paul

 

[Harry Vanderveen]

PVS i have 583 heads, 7736 cam, new stock bore piston kits going in, and im thinking the builder talked about 10.5 to 1, stock stroke,

 

[425/409ER]

We run 2 of the Eddy 500 AVS carbs on out 409 dual quad setup now. It does run pretty well.