JeffReed

Took a drive from Central PA to Ocean City, MD this weekend. The drive down was 65-75 mph with some stop and go at a toll both for about 15 minutes. We also got off the highway for about 15 miles to see a relative in Annapolis. Total miles was a little over 220. MPG was just a bit over 24. I have a 68 vette with a 385 fastburn crate motor and a 670 holley carb.

The noise level of course was much less than last year's trip which made the highway trip very enojoyable. Once I reduce some of my heat inside the cabin, it should be a very easy all-day driver.

GTR1999

What rear gears are you running and what tranny?

flynhi

get some koolmat for heat and sound control in one application.

JeffReed

My rear axle ratio is 3.36:1 and my tire size is 245/45-ZR17. The tranny is the Tremec with the .65 over drive. I purchased the kit from Keisler.


[Modified by JeffReed, 11:00 PM 5/23/2004]

JeffReed

Thanks for the tip on the koolmat. I have a bunch things I need to do to address the heat. Its never been at the top of the list, but its getting there...

GrandSportC3

That's some great gas mileage!! :thumbs: :thumbs:

I get around 17 mpg if I go 65 mph with my '68.. However - my '68 is a lot more radical than your engine... BTW - I'm running a TKO with 3.73 rear gears...

ddecart

Cool!
I'm hoping to do a lot better than the 14mpg I got last year going to the cruise in.

Let's see.... 14/.63=22mpg :eek: No way! I'll be happy with 18.

Fevre

But Dave you got to factor in wind resistance at 90 mph instead of 60. :)

burners

Wow, that is just awesome. I'm hoping to get 18-20 mpg on my trip to the Cruise in with the EFI dialed in (this is with 3.73 gears and a T-10).

Pauld

That is great mileage, just wish my 'vette could achieve that. :rolleyes:

joe73vette

That settles it, I'm getting an overdrive tranny! Joe

turtlevette

sorry, i just don't believe it. maybe you are miscalculating. How much gas did you use?

JeffReed

Dude, don't insult me! I know that 5 out of 4 people have a problem with math, but I ain't one of them. Seriously, I did the math on the back of a business card at the gas station, made a mental note that it was slightly higher than 24mpg and then tossed the card. You're welcome to take a 200 mile round trip with me down the PA turnpike and then fill my tank and do your own math. Given the right circumstances (like driving the speed limit), I think I could do better than 24mpg.

Eddie 70

Nice results Jeff. Those are awesome numbers. I have no idea what mine gets with my combo but I have the same tranny and gearing. I will have to give it a shot when I get my car back.

turtlevette

sorry,

i used to have a 283 with leaned out QJ and 3.08s and 700R4 driving to work everyday babying it at 50 mph the best i ever did was 17 MPG.

You would have used just a little over 9 gallons or around 1/2 tank.

As Sotty says, Captain i can't change the laws of physics.

PRNDL

Jeff, not to insult you, but I would like to see you get more data. Were you able to fill the tank right up to the filler neck both times? I never fill my tank all the way up, so I can never really tell how much gas I used between 2 fillups. I know on my 68 I could easily be 2 gallons off between 2 different gas-her-ups. :)

lostpatrolman

woah..... settle down tiger :smash:

ZL1powr

Jeff's numbers are very believable to me. On my last trip to Indiana and back (990 miles) I averaged a little over 19 miles per gallon with my 489 cu in big block. With out the ROD 6 spd I usually averaged no better than 14 on a trip. On short trips around the area traveling with my buddy (1970 lt-1 small blk), I always require less gas at fill ups. An overdrive trans along with a good tune makes a big difference in fuel consumption.

AlwaysWave

I don't doudt the 24 mpg at all. I've hit 22 crusing at a steady 60 twice, and without overdrive. BTW, I'm waiting on my 5 speed from Keisler. Might get that baby in this year yet. :cheers: