Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Optimum Speed for Best MPG?

Thread Tools
 
Search this Thread
 
Old Dec 19, 2001 | 09:26 AM
  #1  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Optimum Speed for Best MPG?

I thought that somebody might've done a comparison on similar roadtrips and found that they got better mileage at xx mph than at xx mph. I would think that with our 6th gear, the optimum speed would be higher than on most cars. I wish we had an onboard MPG gauge like Caddy's have just to know...

Just curious what you guys think that speed might be...I've got my own ideas, but wanted to hear from ya'll first...

Later
Reply
Old Dec 19, 2001 | 09:49 AM
  #2  
James1's Avatar
Launching!
 
Joined: Nov 2001
Posts: 225
Likes: 0
From: Ft. Worth, TX
Default Re: Optimum Speed for Best MPG?

90mph at 2k will get you a pretty good gas mileage and where you're going fast. But probably the optimal is about 65.
Reply
Old Dec 19, 2001 | 11:26 AM
  #3  
Nightclaw's Avatar
Launching!
 
Joined: Nov 2001
Posts: 245
Likes: 0
From: Over There!
Default Re: Optimum Speed for Best MPG?

I don't think I've ever sustained 65 long enough to measure fuel mileage at that speed - LOL!! <img src="gr_grin.gif" border="0"> My experience has been that, on a straight highway run (say from San Diego to Las Vegas), my mileage is roughly the same whether I hold 70 MPH or 80 MPH. That's not enough of an RPM/engine load difference to show any significant fuel cost/savings. At most, on my Z28 anyway, the difference is about 2 MPG going from 70 to 80. <img src="gr_stretch.gif" border="0">
Reply
Old Dec 19, 2001 | 11:28 AM
  #4  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by Nightclaw:
<strong>I don't think I've ever sustained 65 long enough to measure fuel mileage at that speed - LOL!! <img src="gr_grin.gif" border="0"> My experience has been that, on a straight highway run (say from San Diego to Las Vegas), my mileage is roughly the same whether I hold 70 MPH or 80 MPH. That's not enough of an RPM/engine load difference to show any significant fuel cost/savings. At most, on my Z28 anyway, the difference is about 2 MPG going from 70 to 80. <img src="gr_stretch.gif" border="0"> </strong><hr></blockquote>

With 70 or 80 being 2 mpg better?
Reply
Old Dec 19, 2001 | 03:40 PM
  #5  
Viper's Avatar
12 Second Club
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (6)
 
Joined: Dec 2001
Posts: 4,909
Likes: 3
From: Cleveland, OH
Default Re: Optimum Speed for Best MPG?

I have tracked it ( tho difficult keeping it at one speed <img src="graemlins/gr_devil.gif" border="0" alt="[devil]" /> ) and found in my M6 anything above 63mph caused the mpg to depreciate quickly. Maintaining that speed, I got 32mpg.
Reply
Old Dec 19, 2001 | 03:45 PM
  #6  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by Viper:
<strong>I have tracked it ( tho difficult keeping it at one speed <img src="graemlins/gr_devil.gif" border="0" alt="[devil]" /> ) and found in my M6 anything above 63mph caused the mpg to depreciate quickly. Maintaining that speed, I got 32mpg.</strong><hr></blockquote>

63 <img src="gr_eek2.gif" border="0"> Don't think I can pull that off! <img src="gr_grin.gif" border="0">
Reply
Old Dec 19, 2001 | 03:49 PM
  #7  
Viper's Avatar
12 Second Club
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (6)
 
Joined: Dec 2001
Posts: 4,909
Likes: 3
From: Cleveland, OH
Default Re: Optimum Speed for Best MPG?

Trust me, I'm no longer worried about mpg! I drive on the highway in 3rd and 4th.
Reply
Old Dec 19, 2001 | 04:10 PM
  #8  
LS1powerN20's Avatar
TECH Enthusiast
 
Joined: Nov 2001
Posts: 670
Likes: 0
From: Houston/Lubbock, Tx.
Default Re: Optimum Speed for Best MPG?

It depends on what gear you have in your car (i.e. 2.73, 3.42, etc.)
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-1

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-2

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-3

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-4

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-5

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-6

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-7

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-8

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-9

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
Old Dec 19, 2001 | 04:13 PM
  #9  
Nightclaw's Avatar
Launching!
 
Joined: Nov 2001
Posts: 245
Likes: 0
From: Over There!
Default Re: Optimum Speed for Best MPG?

[quote]With 70 or 80 being 2 mpg better? <hr></blockquote>
Generally speaking, 70-75 MPH gives me between 1-2 MPG better mileage than 75-80 MPH. <img src="gr_stretch.gif" border="0">
Reply
Old Dec 19, 2001 | 04:13 PM
  #10  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by LS1powerN20:
<strong>It depends on what gear you have in your car (i.e. 2.73, 3.42, etc.)</strong><hr></blockquote>

I'm talking about 6 spd with stock 3.42 gearing...
Reply
Old Dec 20, 2001 | 08:59 AM
  #11  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

Anybody else?
Reply
Old Dec 20, 2001 | 09:11 AM
  #12  
buschman's Avatar
TECH Fanatic
 
Joined: Dec 2001
Posts: 1,220
Likes: 0
From: Germantown, MD
Default Re: Optimum Speed for Best MPG?

I get about 30mpg in 6th gear rhovering around 68-70mph.

Buschman
Reply
Old Dec 20, 2001 | 09:14 AM
  #13  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by buschman:
<strong>I get about 30mpg in 6th gear rhovering around 68-70mph.

Buschman</strong><hr></blockquote>

Can you give so more details as to how you did this? Was it during the day? Flat roads? Did you use cruise control or not? Just curious...
Reply
Old Dec 20, 2001 | 07:37 PM
  #14  
buschman's Avatar
TECH Fanatic
 
Joined: Dec 2001
Posts: 1,220
Likes: 0
From: Germantown, MD
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by hankd:
<strong>

Can you give so more details as to how you did this? Was it during the day? Flat roads? Did you use cruise control or not? Just curious...</strong><hr></blockquote>

It was on a relatively flat road. About a four hour drive. It was a summertime trip to the beach. The first and only long trip I've taken this car on so far. I was thoroughly impressed that a V8 could get that kind of millage. I got over 400 miles out of that tank. Most of the trip was on Cruise but when I went through town with stop lights I was in control. I found that the lower your RPMs the better your gas mileage. Just as long as you aren't so low that you don't have enough power to move along without having to lay on the gas pedal. At 68-70 I'm at about 1500-1600 RPM and can handle any hill or flat surface without dumping a bunch of gas.

Buschman
Reply
Old Dec 20, 2001 | 10:47 PM
  #15  
DriveATransAm's Avatar
TECH Junkie
 
Joined: Nov 2001
Posts: 3,029
Likes: 0
From: Chi-Town
Default Re: Optimum Speed for Best MPG?

i think having the car off netted the best MPG for me. i noticed A4s arent replying much <img src="gr_grin.gif" border="0"> we dont wanna calculate ours, hehe.
Reply
Old Dec 20, 2001 | 10:55 PM
  #16  
Toxic Texan's Avatar
TECH Senior Member
 
Joined: Nov 2001
Posts: 8,423
Likes: 0
From: Friendswood,TX
Default Re: Optimum Speed for Best MPG?

I get 22-24 mpg per tank. That is city and highway. Plus that is with some street action. As for best speed.... I couldn't tell ya, but the state of Texas thinks it is 55mph. <img src="gr_images/icons/mad.gif" border="0">
Reply
Old Dec 21, 2001 | 08:09 AM
  #17  
hankd's Avatar
Thread Starter
Staging Lane
 
Joined: Nov 2001
Posts: 73
Likes: 0
From: Ft Worth, Tx
Default Re: Optimum Speed for Best MPG?

[quote]Originally posted by Blank:
<strong>I get 22-24 mpg per tank. That is city and highway. Plus that is with some street action. As for best speed.... I couldn't tell ya, but the state of Texas thinks it is 55mph. <img src="gr_images/icons/mad.gif" border="0"> </strong><hr></blockquote>

55? Where? Most of the limits around here are 65...which means 75'ish...

Sounds like we're getting similar mileage under similar conditions. I usually get 21-22 during the week, 24 on roadtrips...
Reply




All times are GMT -5. The time now is 06:55 PM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE