holley double pumper. Finding out size and other ?s

[72gsBuick]

I found an old holley double pumper carb in all the parts ive collected over time, and was wondering is there a way of determining the size of the carb, meaning cfms without a chokehorn, i guess the choke horn has been milled off so i dont know what size it really is.. on the other hand assuming its a 600 cfm can you swap the body for a bigger cfm body. its currently going a 455 so i guess i need a 800+ carb for mine. can you tell by the size of the butterflies.. thanks

[sootie007]

Maybe this will help ...butterflies on my newer Holley 850 double pumper are stamped 180....my 750 Barry Grant Double pumpers - Speed Demon are stamped 169. Here is a link to some baseplates and their cfm ranges...scroll about 1/2 way down the page......... . http://www.carburetion.com/holley.asp

[DaWildcat]

I found an old holley double pumper carb in all the parts ive collected over time, and was wondering is there a way of determining the size of the carb, meaning cfms without a chokehorn, i guess the choke horn has been milled off so i dont know what size it really is.. on the other hand assuming its a 600 cfm can you swap the body for a bigger cfm body. its currently going a 455 so i guess i need a 800+ carb for mine. can you tell by the size of the butterflies.. thanks

Give us the diameters of the butterflies, a few pics and we can go from there figuring it out.

Devon

[72gsBuick]

both the front and back butterflies are stamped with the numbers 172...i will try posting pics tomorrow..thanks

[72gsBuick]

This website is pretty good reference site..I noticed that the 3310 baseplate does have the 172 172 butterflies, also that it is a vac secondary, but mines is not a vac secondary, i will try getting a pic tomorrow, as soon as i pick it up.. i also noticed the numbers 4778 numbers on the metering blocks... anyways ill post pics tomorrow.

[RG67BEAST]

If you post the main body number I have a Holley book that has the metering block #s and base plate#, jets, power valve(s) & shooters etc it had when made. If there is no body id # the book also has the size of veturi's and throttle bores, fuel bowl part #'s etc to figure out what you have.
Ray

[Guy Parquette]

The "4778" is the list number which can be found also on the metering blocks.

So a "4778" is a 700 CFM double pumper carb.

[72gsBuick]

i will try to get all the info tomorrow...thanks

[72gsBuick]

sorry guys i had the carb at the machine shop (cleaning) after a while of waiting, it was not cleaned...:eek2: anyways here are the pics..what pics do you need to determine what size this is..even though i bought a quickfuel 830 s/s i still want something to work on and build. thanks

http://i228.photobucket.com/albums/ee107/1972gs1969/DSC01903.jpg

http://i228.photobucket.com/albums/ee107/1972gs1969/DSC01905.jpg

http://i228.photobucket.com/albums/ee107/1972gs1969/DSC01908.jpg
http://i228.photobucket.com/albums/ee107/1972gs1969/DSC01907.jpg