The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Putting miles on 67, 402bbc VS 67 V6 305E

geezer#99 · 05-09-2023, 10:30 AM

Here’s a mileage kicker for you!
Bought a 70 chevelle ss454 back in 1978. LS6, m22 and 3.08 gear. Previous owner didn’t like the solid lifter cam so he had a stock bb cam installed. Same basic cam as in your 402.
Highway driving at 65 mph it would get 22 mpg. That’s a Canuck gallon. Same as 18 mpg in US gallons. While it sipped fuel it was a real dawg to drive. Ran out of breath at 4500 rpm.
Drove it like that over the winter. In the spring swapped the cam to a LS6 spec but it was a hydraulic cam.
Took care of that gas sipping dawg. Dropped it back to 15 mpg in Canuck gallons. Awesome power difference. Would light em up all the way thru 3rd even with the 3.08 gear.
And now back to your regular programming.

05-09-2023, 10:30 AM	#26
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,521	Re: Putting miles on 67, 402bbc VS 67 V6 305E Here’s a mileage kicker for you! Bought a 70 chevelle ss454 back in 1978. LS6, m22 and 3.08 gear. Previous owner didn’t like the solid lifter cam so he had a stock bb cam installed. Same basic cam as in your 402. Highway driving at 65 mph it would get 22 mpg. That’s a Canuck gallon. Same as 18 mpg in US gallons. While it sipped fuel it was a real dawg to drive. Ran out of breath at 4500 rpm. Drove it like that over the winter. In the spring swapped the cam to a LS6 spec but it was a hydraulic cam. Took care of that gas sipping dawg. Dropped it back to 15 mpg in Canuck gallons. Awesome power difference. Would light em up all the way thru 3rd even with the 3.08 gear. And now back to your regular programming.