Best fuel mileage?

john chesnut · #1 (**permalink**) 10-09-2011, 02:21 PM

Yes, I know that owning a Cobra is not about economy or fuel mileage. But, I was shocked when I checked my fuel mileage this weekend. I filled my tank in Grantham, NH Saturday night. My son drove my Cobra to our home in the Adirondacks of NY. He followed me while I drove the truck and car trailer. We were on freeway to Burlington, Vt. Secondary roads from there to our home in Elizabethtown, NY. (Took a ferry, but DIDN'T count those miles).
On Saturday morning my wife and I drove the Cobra to Ticonderoga, NY and meet up with a cool group of VT Cobra owners for a day trip through the Adirondacks. I filled the car in Ticonderoga and it took 5 gallons even. I couldn't squeeze in another drop. That is 190 miles on 5 gallons! 38mpg!

My car has a Shell Valley body. I built the frame. The drivetrain is 2003 Z06 vette. I used the stock 405hp LS6 engine, stock 3:42 diff, and vette suspension narrowed to fit the Cobra. The trans is a double overdrive T56 from a Camaro.

My car is plenty fast for me, handles great, the fuel efficiency is a bonus.

twobjshelbys · #2 (**permalink**) 10-09-2011, 03:33 PM

I get 20+ on the freeway when going in 5th at 75 +/-. Roush 427IR fuel injected. This is mountains around here so it's always going up or down, rarely flat.

Silverback51 · #3 (**permalink**) 10-09-2011, 04:17 PM

Last year on vacation I averaged 8.5 MPG for the trip.

Guess I will not win any awards, but I do get a personal Christmas card from OPEC.

fordracing65 · #4 (**permalink**) 10-09-2011, 05:38 PM

26 mpg, 80 mph, 6th gear, 1700rpm, ford racing t50 cammer

fordracing65 · #5 (**permalink**) 10-09-2011, 05:41 PM

Quote:

Originally Posted by john chesnut

Yes, I know that owning a Cobra is not about economy or fuel mileage. But, I was shocked when I checked my fuel mileage this weekend. I filled my tank in Grantham, NH Saturday night. My son drove my Cobra to our home in the Adirondacks of NY. He followed me while I drove the truck and car trailer. We were on freeway to Burlington, Vt. Secondary roads from there to our home in Elizabethtown, NY. (Took a ferry, but DIDN'T count those miles).
On Saturday morning my wife and I drove the Cobra to Ticonderoga, NY and meet up with a cool group of VT Cobra owners for a day trip through the Adirondacks. I filled the car in Ticonderoga and it took 5 gallons even. I couldn't squeeze in another drop. That is 190 miles on 5 gallons! 38mpg!

My car has a Shell Valley body. I built the frame. The drivetrain is 2003 Z06 vette. I used the stock 405hp LS6 engine, stock 3:42 diff, and vette suspension narrowed to fit the Cobra. The trans is a double overdrive T56 from a Camaro.

My car is plenty fast for me, handles great, the fuel efficiency is a bonus.

Your getting better mpg than a honda civic with 130 stock hp , your gauge is wrong.

twin turbo · #6 (**permalink**) 10-09-2011, 05:43 PM

That is amazing. I know the newer vettes can get high 20's mpg. I would think the lighter weight of the Cobra would be handicapped by the significantly inferior aerodynamics. Just doesn't seem to add up. Cheers.

Cobrajames · #7 (**permalink**) 10-09-2011, 05:51 PM

I am averaging 13 mpg in my SB 427 with TKO600(.82 5th) and 3.46(?) BTR rear end. About half and half street/highway. Not much to brag about.

terry mason · #8 (**permalink**) 10-09-2011, 06:18 PM

Took a trip out old 66 and up the Pacific Coast highway a couple of years ago and averaged 21mph. slab side with a 302 roller motor and t-5 3:5 9" 7500 miles in 31 days.
Great Trip!

terry mason · #9 (**permalink**) 10-09-2011, 06:21 PM

Took a trip out old 66 and up the Pacific Coast highway a couple of years ago and averaged 21mph. slab side with a 302 roller motor and t-5 3:5 9" 7500 miles in 31 days.
Great Trip!

Dwight · #10 (**permalink**) 10-09-2011, 06:39 PM

last June I checked my mileage on the trip to London Cobra Show, 1130 miles. I got a little over 20 mpg.
I have a stroked 302 fuel injected making 400 rear wheel horsepower.

I think I would have got better but I drove 300 miles in the rain to get home, but I saved a little by getting blackballed on Main Street on my first run.

Dwight

YerDugliness · #11 (**permalink**) 10-09-2011, 08:17 PM

Last time I checked I was getting around 24 mpg. My Cobra has what I THINK is a box-stock '89 5.0HO/WC T-5 from an '89 Mustang GT, 9" 3.70 gears with posi. I actually like the way it sounds at about 65 mph in that 5th gear (.63 OD, I think) with earmuffs on, smooth, a low pitched rumble with enough "snarl" to make it interesting, so I probably spend most of my time around 65 mph on the highway. In town I drive it like a wimp, don't like the way the red car attracts the attention of every lawman within sight, but once I turn onto the highway, I drive it like I suspect most of us drive....in what I would call "...a spirited manner

".

Cheers, Dugly

Zoom This · #12 (**permalink**) 10-09-2011, 08:29 PM

Drove my SPF on a 3k mile, 8-day road trip last year from Washington state to Canada, Wyoming, Montana etc., etc. I averaged 16 mpg for the whole trip. Montana highway speeds were 90-100 mph. Car has a 418W, 550 hp, Tremec 5 speed OD. Car has gotten 18-20 mpg on the freeway at 70 mph. Around town?....8-10 mpg.

Dirty Harry · #13 (**permalink**) 10-09-2011, 08:52 PM

13-16 in mixed driving, 22 on the interstate, fairly mild 358 with 3.25 gears

Jimeg · #14 (**permalink**) 10-10-2011, 07:53 AM

Gentlemen, nothing wrong with getting good fuel economy, I envy you guys. I have clocked 2,200 mi on my Roush 427SR/TW 515hp. and the best I get on all all highway trips is 12.6 mpg. Around town I'm getting around 8 mpg.

Jerry Clayton · #15 (**permalink**) 10-10-2011, 08:00 AM

So John is the only one that drafted a truck and trailer close and used a ferry???

jbmatth · #16 (**permalink**) 10-10-2011, 09:02 AM

I took mine on about a 1000 mile trip last summer mostly on I-44 to St. Louis and got 18-19 for the whole trip, I don't check it in town. But it does do better than my 4 cyl truck on the highway, and way more fun too.

john chesnut · #17 (**permalink**) 10-10-2011, 09:47 AM

I know the number sounds ridiculously high. I had never actually checked the fuel mileage but always thought that it was around 30mpg.

My car was designed so that all of the air going through the radiator exits the side of the car. It can not get into the engine compartment. My frame comes to a vee in the front and diverts the air out the side. I have an extra set of side vents and because of the frame design I do not have inner fender liners. My radiator sits straight up and down and is only 12 inches high and 18 inches wide. It has never overheated, even racing, so I know that my air flow is pretty good.

My son did follow behind my trailer, The trailer was loaded so I was going 60-62 on the freeway. I didn't count the 3 mile ferry ride.

I have a custom made racing fuel cell. I do not use the the Cobra fill cap to fill the car. I can see the fuel when filling and quit filling when it touches the lower edge of the recessed cap locking prongs.

Got to go. Taking the Cobra for an afternoon drive while the fall colors are still good and it's warm.

john chesnut · #18 (**permalink**) 10-10-2011, 09:58 AM

Sorry, double post.

ha_pe_1968 · #19 (**permalink**) 10-10-2011, 10:48 AM

Hi!

Wow really impressed about some mpg's!!!!

I am far away from it...the best i ever had was on a long
highway drive in the rain... 16 mpg

Normally i am at 9-10 mpg...most driving on small mountain roads.

Its a Roush 427R with a 870 Holley and a dual intake - 450 RWHP

Glad that this car is only a toy...if i would use this car everyday it would make
me to a poor man with our petrol prices.

My old 1970 454 Auto Corvette needs 14 mpg at the same montain streets at more or less the same speed ...less HP and more weight

But the Cobra makes more fun on small montain roads as the Corvette...seems fun has nothing to do with economic

(in my case)

Peter

Jerry Clayton · #20 (**permalink**) 10-10-2011, 11:04 AM

Last night I was fueling up my F350 diesel and next to me was a guy and gal with a pair of Harleys--I asked him if he wanted to switch fuel bills with me----then got into a discussion of the milage that he gets---aprox 35 mpg!!!!then he asked me and I told him the 19 that we average---he says"Boy, sure glad they got 35 because they couldn't afford to travel at my fuel cost"" I didn't botter to tell him that the math when I went to school would have my fuel costs less because he had TWO at 35 mpg which equates to 17.5 !!!!!!