I am having some issues with the carb on my '77 400 big block in my duster.
The carb is a 750 cfm Holley 3310 4 bbl with vacuum secondaries.
-main jets are #72
-6.5 power valve
-green accelerator pump cam
-.025 accelerator pump nozzle
-Quick Fuel Technologies secondary diaphragm housing
I got it used and rebuilt it when I rebuilt my engine ~5 or 6 years ago. Rebuilt everyting back to the factory specs listed in my holley carb manual, except for the aftermarket diaphragm housing. The problem is a lack of torque off-the-line with this carburetor and a very slight "flat spot" when applying very light throttle from cruise. When heavier throttle is applied from cruise, there is no hesitiation.
It does NOT bog off the line, although bottom end torque is not spectacular. I had chalked this up to the engine combination UNTIL I installed an older, used 600cfm edelbrock performer carb on the car to see if that affected the slight hesitiation from cruise. When I installed the Edelbrock carb, this thing suddenly turned into a tire-burning torque monster, much to my surprise.
This tells me that there is definitely something wrong with my Holley, but I don't know where to look. I would like to fix the holley and put it back on since it provides noticeably better midrange and top-end power over the smaller edelbrock carb. Does anyone know what might cause such a problem? Thanks!
The carb is a 750 cfm Holley 3310 4 bbl with vacuum secondaries.
-main jets are #72
-6.5 power valve
-green accelerator pump cam
-.025 accelerator pump nozzle
-Quick Fuel Technologies secondary diaphragm housing
I got it used and rebuilt it when I rebuilt my engine ~5 or 6 years ago. Rebuilt everyting back to the factory specs listed in my holley carb manual, except for the aftermarket diaphragm housing. The problem is a lack of torque off-the-line with this carburetor and a very slight "flat spot" when applying very light throttle from cruise. When heavier throttle is applied from cruise, there is no hesitiation.
It does NOT bog off the line, although bottom end torque is not spectacular. I had chalked this up to the engine combination UNTIL I installed an older, used 600cfm edelbrock performer carb on the car to see if that affected the slight hesitiation from cruise. When I installed the Edelbrock carb, this thing suddenly turned into a tire-burning torque monster, much to my surprise.
This tells me that there is definitely something wrong with my Holley, but I don't know where to look. I would like to fix the holley and put it back on since it provides noticeably better midrange and top-end power over the smaller edelbrock carb. Does anyone know what might cause such a problem? Thanks!