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piecesparts · 05-26-2007, 11:06 AM

I take it, that your carb is the factory MESS and the computer in your truck is still involved in your system. The quadrajet is a good carb, but after a number of years is definitely due for a rebuild. If it is one that has computer controls, I never got along with them very well. The timing is very important, but if you still run the computer, that is hurting you. I took my 84 and my Son's 86 to HEI distributors and got better performance and tuning capabilities from that change. I eventually ditched the computers, air pumps, and anything else that would hinder performance in my engines---In Kansas the smopggies are not alive and well.

The discussion on tire size and gearing is important here. My Son's truck had 3.08 gears in the rear and with the 700R4 tranny that we installed, his gas m ileage was around 12 MPG. We changed to 3.73 gears and GAINED 2 MPG just because he was running outside the power curve of the motor. I get 15 MPG with my 84 stroker motor. We are NOT using the factory carbs anymore.

05-26-2007, 11:06 AM	#11
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	Re: Gas mileage/carb question?? I take it, that your carb is the factory MESS and the computer in your truck is still involved in your system. The quadrajet is a good carb, but after a number of years is definitely due for a rebuild. If it is one that has computer controls, I never got along with them very well. The timing is very important, but if you still run the computer, that is hurting you. I took my 84 and my Son's 86 to HEI distributors and got better performance and tuning capabilities from that change. I eventually ditched the computers, air pumps, and anything else that would hinder performance in my engines---In Kansas the smopggies are not alive and well. The discussion on tire size and gearing is important here. My Son's truck had 3.08 gears in the rear and with the 700R4 tranny that we installed, his gas m ileage was around 12 MPG. We changed to 3.73 gears and GAINED 2 MPG just because he was running outside the power curve of the motor. I get 15 MPG with my 84 stroker motor. We are NOT using the factory carbs anymore.