Mileage question
 

Probably a stupid question, but, I have a 1978 K10 with a 1992 350cid, 700r4 trans, np241c, Rochester 4bbl (just rebuilt) just tuned up and oil change. I'm running 33's but not sure of the gearing. my question is, I'm getting about 3-5 mpg city! is this normal??? (it may also have a mild cam)

Re: Mileage question
 

should be getting better than that!!

Re: Mileage question
 

You got a few unknown variables to your mileage equation. Gearing? Is the speedo/odometer accurate? Without accurate mileage, you can't correctly calculate your MPG's. Given that you have a 241 and 700r4 swapped into a 78 it may not have the correct speedo gear for your combination.

So to answer your question, 3-5 mpg city does seem low. But not far from what might be going on. 33" tires with highway gears causes more effort to be made to get rolling, that equals more fuel being used to get up to speed. You need to fill in the blanks to get an accurate mileage reading.

Re: Mileage question
 

use a GPS to determ'n if your speedometer is correct and go from there, my call is the speedo is way off.