Qjet to 2bbl swap?

[Scruffy49]

The factory installed Qjet on my truck is at paperweight status. It basically sweats gas.

Ordered the adapter to run a 2bbl on the stock high rise iron intake.

Pulled the original issue 40 years old distributor yesterday. New distributor, plugs and wires going in today.

Truck has a Th400 and 2.73 gears. Dual pcv valves, breather type oil filler cap, and still has the evap system. So will have to run a Ford style pcv compatible base gasket. 500cfm capable Holley.

Curious as to what drivabilty issues I should expect. Truck is an 85 C10 swb, with a 4.3L V6…

 

[Tank6x2]

Slow off the line but great legs once your up and going with good fuel mileage

 

[fast 99]

A Q-jet has smaller primaries than a 2 V Holley 500. Provided your foot doesn't open the secondaries Q-jets are an economical design.

 

[82sbshortbed]

Yup just keep your foot out of it and it will be a 2 barrel. You can here the back barrels open if you mash to hard.

 

[Scruffy49]

Just put a Qjet back on, throttle everything is incompatible. Holley is going on the 318/727 combo it was initially purchased for. I do have a GM 2bbl I could try, but it is governed.

 

[GTX63]

Speaking from experience and as someone who drove them back in the day like granny with a short leg, I never, ever experienced better gas mileage with a Rochester 2bbl over a Qjet. All things equal, there may be a 20% difference, or less, in mpg between it and a V8.

 

[PrairieDrifter]

I had a secondary problem, tried staying out of the secondaries. Realized how LITTLE I use the secondaries, I'm lifted on 35's too. Hardly ever got into the secondaries with normal driving. I was pretty shocked.

 

[Ricko1966]

I had a secondary problem, tried staying out of the secondaries. Realized how LITTLE I use the secondaries, I'm lifted on 35's too. Hardly ever got into the secondaries with normal driving. I was pretty shocked.

This is why on a qjet you do all your jetting and tuning on the primary first,most of your driving is on the primaries. Don't change secondary hangers,rods or spring windup until you have the primaries dialed in.