Hey guys i'm currently running a mild 350 with a q-jet 800. Ive had this set up for approx 4 years and havent had any issues until recently. Now it seems everytime I run it hard, ill turn about 5000rpms in 2nd gear and the engine will bog down. I ran some carb cleaner through it and it seemed to work for a short period of time. I'm at the point of switching carbs...any suggestions?

 

Sounds like your running out of air or fuel to get the high Rpm Bog. What is your carb off of? most Q - jets are rated at 750 cfm. if the carb is off a 305 motor, it probably will not be supplying enough fuel. Do you know what primary rod size, jets and secondary rods the carb has? I'm currently tuning my 83' q-jet of my LG4 305 to work well on my 355 sbc as well.

 

Mine is off an '80s truck. My dads friend rebuilt it he swears by them. For the metering rods and such I have no clue. I just dont understand why it ran great for so long and all the sudden like garbage.

 

If it ran OK before, have you made any changes recently? How is your ignition? is it HEI ? plug wires OK? has the timing moved? Maybe the float/ needle seat/ fuel filter is screwed up inside the carb restricting fuel flow? All good places to start. I agree the q- jet can be a great carb if you set them up correctly.

 

check the filters. Or pump could be weak

 

X2