CarburetorsCarb discussion and questions. Upgrading your Third Gen's carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
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How to tell the difference between 650 and 750 double pumper?
I was wondering how to tell the difference between a Holley 650 and 750 double pumper? I need a 750 double pumper and my cousin down the road has a holley carb and he's not to sure what it is. How can I differentiate the carb?
Zach
__________________ 91 Firebird Formula 355 small block, 4 bolt main, Forged Wiesco Pistons, Stage II connecting rods, Stock re-ground crank, Dart Iron Eagle 215cc/64cc Cylinder heads, 246/246 @ .050 .532/.531 Solid lifter Camshaft, Holley 650 DP, Edelbrock Performer RPM Intake, T-56 Trans w/ Centerforce DF clutch, 3.73 Richmond gears w/ Zexel posi unit. UMI SFC's, Lakewood RLCA's, new front suspension. Hooker Super comp's, Custom 3" Y-pipe, Custom 4" exhaust over axle, Dynomax Bullet muffler.
(I think) There should be some numbers on or around the choke horn. Get thease numbers and do a search online.Or, If you knew what size throttle bores a 750 dp has you could flip the carb upside down and measure the diameter of the throttle plate bores with calipers. I wish I could help you more.
750 is a 4-corner idle carb, and a 650 is not. IIRC, that means that the 750 will have idle mixture screws on the rear metering block, and the 650 (like mine) will not.
On the choke horn, it will also have the PN that will identify the carb. 650 is 4777, and a 750 is 4779.
750 is a 4-corner idle carb, and a 650 is not. IIRC, that means that the 750 will have idle mixture screws on the rear metering block, and the 650 (like mine) will not.
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