Highest MPG V8?

[jcp123]

The Vette and Camaro both, with the LS/1 V8 had that massive .5:1 6th gear which took revs down to ~1400 @ 65. While they were never actually rated at 32mpg, many owners of both cars have touched 30+ and most can consistently and easily pull better than 27.

LT/1-equipped cars like the Cadillac Fleetwood and Chevy Impala SS, among others, were capable of mid-20's, not bad for a 4000lb+ V8 car. Similarly, the Cadillacs with Northstar V8's are known for getting ~27mpg on the open road with little effort.

Some folks have swapped EFI onto their vintage Mustang small blocks and together with a 5-speed manual swap get 25+, some even claim 30 highway.

My best was 22mpg in my '68 Mustang. It had a 302 and no overdrive, but it had the tallish 2.73:1 rear end and the hardtop body was the lightest bodystyle weighing in at ~2750lbs. I got that on the flats of the Central Valley, CA, doing about 60 on Interstate 5 with freshly aired up tires. It was a bit of a freak tank, I usually got 18-19mpg at that speed. May have been the Flying J pump I got gas at...

[GasSavers_RoadWarrior]

Originally Posted by jcp123

Similarly, the Cadillacs with Northstar V8's are known for getting ~27mpg on the open road with little effort.

I knew there was a good reason to drop a Northstar in my minivan....