MPG check out run.

Welp, I got the opportunity to drive a 420 mile loop today. had to deliver a buddy to Ft. Lauderdale airport.

Thought it would be a good chance to get a base line for gas mileage on the "new to me" '89 Buick Boxie, AKA the Way Cool Wagon.(Old's 307 Y motor/THM 200 4R)

Rolled out of Venice at 5:30 AM held 78 MPH (very light traffic) all the way to the Airport. A/C off, Averaged 16.5 MPG. (~62 deg. clear/dry.)

The speed limit on that stretch of I-75 is 70 MPH. It's known as Aligator alley and anything under 80 is pretty well tolerated by the FHP, with reasonable lane discipline. (in the wee hours, it's not unusual to be passed by South Beach screamers at 160+MPH)

On the return trip, I held a steady 65 MPH. A/C off, Averaged 18.8 MPG. (73 deg., clear, calm)

The WCW is averaging ~ 13.5 to 14.0 MPG with mostly careful in town driving.

Seems a little low, for a baseline, but it's a place to start.  Wadda ya'll think?

Any input as far as tuning handles, tip's and tricks would be greatly appreciated.

As usual, smart azzed remarks and sarcasm will be cheerfully read and  graded for content.

Thanks, Paul

seems about right. maybe 1-2mpgs out?

We did an average with the OCC of 17 mpg however, i replaced the Rochedster and have an Edelbrock 600 4 barrel on top of it with vacuum secondairies. (same 307, 20k miles ago rebuild and the 200-4R)
Best we had was 21mpg, doing 65mph on cruise (and tail wind) Our A/C doesn't work anymore.
Your data seems about right.
Pete

Those numbers are spot on. On the BABE Rally back in 2011 we did a MPG challenge for about a hundred miles and Firefly got 19 MPG. That was when it was stock, carried three guys with luggage, no rear shocks, and running the A/C through Alabama. I find the 307's cruising sweet spot is 65-70.

City...ugh...10-12 when you live in NYC. And like to "launch" at a red light.

"launch" a 307?

"launch" = quickly accelerate to 10 mph, then slowly make your way to 25.

Least the true duals make it sound like its powerful.
One day it'll be 3.42s and a 455. Until then...I can dream.

great

I'll be rolling in the Way Back Machine Thursday morning down to Orange, CA. - 1800 mile round trip. I'd be real pleased with 17.5 mpg on the highway. We'll see.........