Who hypermiles their sports car?
 

I just got a C5 Corvette and I have a 530 mile road trip coming up in 2 weeks.

I've done this same road trip with my 6.5 Diesel pickup. I got 21+ MPG going 60 the wholeway so it was really slow. Easily made the trip without refueling because it had a 33 gallon tank.

I've done this trip with my Supercharged Regal and did anywhere from 55-65MPH no WOT runs and got 31+MPG. Couldnt make it without refueling because it has a 17 gallon tank and I chickened out at 450 miles and refueled because the gas light came on.

Im going to do my best to restrain myself in the C5.Its a manual so in 6th gear its doing 1500 RPM at 65 MPH. Im going for 30 MPG so maybe I can make it without refueling. 19 Gal tank.

Anyone hypermile a sports car? What kind of results have you gotten? So its ok to coast downhill in Nuetral on a manual correct?

1,500 rpm at 65? Wow! My car does 3,000 @ 60! It's OK for the car to coast in neutral, but it's illegal in some states. I wouldn't lose any sleep over it.

Yeah when I got the car I was shocked how low its turning in 6th gear at 65.

At 80 MPH its at 2000 RPM in 6th gear.

I really want to go for 30+ though so I'll restrain myself and stay at 65. I use this site as a game. Im a stat freak and my Vette is currently under the EPA rating right now so I have to bring that # up :p

The Durango turns 1750 at 60 :thumbup:

Corvettes actually get pretty decent highway mileage. If you scope out the vette forums you'll see that people regularly get in the low 30s while cruising past 80.

It's the combination of low frontal area and a nice low overdrive.

My truck does 1600-1700 RPM @ 65 MPH.

Hey I had a 1999 Durango and for the life of me it couldnt break 12 MPG no matter how I drove it.

I saw you had a nice 16 mpg run averaging 80 mph.

You ever going to restrain yourself and try a long trip at 65 or slower? I think you can hit 20 :)

I had to drive my 6.5 diesel at 55 MPH to stay under 2000
RPM in order to see 21.7 mpg. It was painful but the stat freak in me wanted to bump my stats up :D

Is it a manual? 5.7 Vortec? My Chevrolet Pick up is a 6.5 Diesel with a 4 speed auto and the only way I can stay under 2000 RPM is to stay at around 55MPH

This year I'll probably be swinging by San Antonio on my way home to visit family this year so I can pick up a dog around Christmas time. Maybe then as it would normally take me nearly 3 tanks of gas to do that trip and being able to do it with 2 would be nice. I have been very curious about what easy driving and a normal highway pace would get me.

Unfortunately, I-10 serves me with a good 200-300 miles out of 1,100(one way) with 80mph speed limit area so that tank won't get treated well both ways.

Its a 98 GMC K1500 with a 4L60E 4 speed overdrive automatic. The engine is a classic 5.7 Liter "350"

-Jay

I noticed you dont have anymods yet. To tide yourself over why not gut the air box? Take a Jigsaw to it or a better tool if you have one and just cut open the biggest opening possible. Im sure your airbox has 1 small hole sucking air out of the fender. Might pick up an extra mile there. Everybit counts :)

I just took the lid off my airbox, but depending on your filter configuration that may not be possible.

-Jay

You should have the vortec motor so basically your airbox is a cone with a box built around it right?

Yeah, The air filter is a huge cylinder that is pressed onto the air intake, and a box around that. I simply took the lid off the box and duct taped the original air intake shut.

Set your goal higher. Plenty of speed freaks report 30mpg+ in their Corvettes without any attempt to save gas at all.

Neutral coasting is fine in most automatics, too. It's shutting the engine off that's not ok in automatics, but is ok in manuals.

You might be able to increase your tire pressure. That will help if it doesn't make the ride unbearable or make the car handle badly. On common economy cars and trucks/SUVs it's easy to pump up the pressure, but it might not be so pleasant on the Corvette. Don't exceed the maximum stamped on the tire sidewall.

And regarding intake modifications...I'm highly skeptical that anyone trying to save gas can improve their fuel economy with a less restrictive intake. If it can flow enough for making maximum power, it should flow totally freely at low RPM/low throttle conditions used by people trying to save gas. The same goes for exhaust.

Additionally, studies have shown that even using a clogged air filter doesn't reduce fuel economy, it just reduces power...

Its an experiment worth trying I think. Its free so why not try?The factory usually has it sucking air through the fender with a small *** hole. If you cut that side off completly you have more surface area to suck in air and you'll suck in a little hot air in as well. Doesnt hot air =better fuel economy?

In my Regal I averaged better Fuel economy with a an open air intake but I was losing time at the track so I built a Fenderwell intake.

Yeah, LS/1 Corvettes and Camaros have a .5:1 overdrive ratio 6th gear, which with the 3.42 they put on a lot of those cars makes it super tall in top gear. Actually, I'm surprised it's 1500rpm at 60, I had thought it was 1400? At least, that's what I read. In any case, I had also heard from a friend of mine with a 35th Anniversary SS Camaro that 75-80 seems to be the sweet spot for fuel economy in these cars with that tall gear.

Anyhow, not really a sports car but I did have an SVT Focus, I got about a 6mpg gain from the mildest of techniques. Despite turning over 2800rpm at 65mph, it was always good for a solid 34mpg on the open road with just a little care. I have a '67 Mustang which is awaiting its new jets and metering rods before I really try in ernest to wring any kind of FE from it.

I tried the air box mod. It let much warmer air in but it started pinging under load and my mileage actually dropped.

I think it had more to do with the iron block and heads and worn out ignition components than anything else.

Im trying to hypermile my camaro. Its an auto so you have a lot taller final drive then I do. And I have a 3000 stall so in town taht causes some issues but I can do better then epa and am getting better.

You should be able to do 30.

Jay ,
I have the same trans bolted to the GM 3.8 90 degree V6 so the thing should last forever !

Highway running is 1750 RPM @ 60 MPH and fuel is around 7.5 lt/100 klms (about 31 US MPG)

Pete.

I know the 3.8 V-6 extremely well. That's the engine that's in my 1981 Buick.

I have a 455 in my Buick, and I have a 2.56 rearend ratio. I wish it could be even taller.

Someday I'm going to figure out how much fuel it takes to spin the engine at 2000 RPM, because I bet that is at least 1/2 of my fuel consumption at 60 MPH.