Highest MPG V8?

[bobc455]

I know that the V8s are generally not known for their fuel economy, but I though I remembered that the Corvettes were rated about 32 MPG highway. I couldn't confirm this, though, since the Chevrolet website only claims 26 MPG highway (still not a bad number).

I also saw the recent article on the Oldsmobile that got good mileage, I think it was about 19 MPG highway.

What other "high" MPG V8s exist?

Anyone (besides myself) have any gas-saving V8 projects in the works?

-Bob C.

[VetteOwner]

even the ol 350 carbed boats of the past got very high teens to mid 20's highways...

we had a Chevy caprice that would get about 19-22 mpg on highway if you drove it right...

[dkjones96]

The Corvette constantly gets mentioned on fuel economy top 20 lists and such.

The Ford Crown Victoria platform 23 freeway on the new rating system. Mustang GT gets 22-23. From personal experience the Crown Vic actually gets closer to 26-28mpg on a constant freeway cruise tho.

Lexus GS 460 gets 24 freeway on the 4.6L V8 as do most of their other V8 cars.

Cadillac STS with 4.6L gets 24 and the Infiniti M45 gets 21

There aren't a whole heck of a lot of V8 cars out there anymore as most companies have gone to 6 cylinder engines. Regardless of that fact though, having V8 cars that are getting int he 20's on the new testing the EPA does is pretty good.

[fumesucker]

'97 Expedition, SOHC 4.6 with a towing package ... 22 mpg actual at 65 mph.

I'm sure with some aerodynamic mods that could be taken to 25 mpg and maybe even higher.

Virtual boattail anyone?

[fumesucker]

95 Mustang 5.0 , 27 mpg actual at 70 mph cruise..

[mjswan]

Check out my "88 Mustang (http://www.gassavers.org/garage/view/1408). With the 5.0 liter V8, 5-speed and 2:73 gearing, I am getting close to 30 mpg regularly on my commute. The torquey V8, manual transmission and high gearing combine for good economy if you drive carefully. The newer cars with more efficient electronics than my 20 year old car should do better.

[GasSavers_RoadWarrior]

I've heard of crown vics pushing into the 30s on the highway, that might have been with some mods though.

[dkjones96]

Originally Posted by RoadWarrior

I've heard of crown vics pushing into the 30s on the highway, that might have been with some mods though.

I should have probably said, that's about an 85mph highway cruise. At 65-70 we actually got around 31-32.

[GasSavers_JoeBob]

I can get around 25-26 mpg out of my '83 Eldorado with the 4.1 liter engine. On one trip I did get about 32 mpg with a lot of drafting...

[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...