If you need a high performance carb for your C3, I highly recommend this Ebay seller. He's been rebuilding and selling carbs on Ebay for nearly fifteen years (Top Rated Seller too!). I put this carb on, only having to adjust the rear float and idle screws and the engine started instantly and idled cold! The carb came with all brand new hardware, screws and even the springs. No bog, no hesitation, no 'flat spot'. Just a hard hitting little beast. He's got six of them on Ebay in varying sizes from 600 cfm on up. All tested, tuned and ready to go. Worth saving this seller.

https://www.ebay.com/itm/Holley-4150...r/264489789543



Holley 4150/600cfm, competition drag racing double pumper carburetor
Holley, 4150/600cfm competition drag racing carburetor, mechanical secondary, 4 corner idle, jet extensions with notched secondary nitrophyl float for hard rapid acceleration, tygon seals on the idle mixture screws, choke horn milled to increase airflow to 650+ cfm and have great low end throttle response, was totally disassembled, vibratory cleaned and polished in a filtered soap and water solution, top and bottom of the base plate is resurfaced, thoroughly gone over, new gaskets with new reusable non stick bowl and metering block gaskets, new accelerator pump diaphrams, new power valve with protector, floats are set, tuning calibrations are pre-set, fuel inlets are installed and pressure tested, mounting gasket is included, this carb. is in like new condition and ready to install. all parts are polished or plated, no paint or powder coating, This type of carb. is at home on the street or strip, Ships worldwide, Check out my feedback. This is an actual photo of the carb. listed. #21