Brought to you in part by:

.

Shop Eastwood for your Auto Restoration Needs!


  Mustangsandmore Forums
  '64 1/2 to '73 -- The Classic Mustang
  Gas mileage

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Gas mileage
FASTFORD
Gearhead

Posts: 105
From: USA
Registered: Aug 2002

posted 09-16-2002 05:12 PM     Click Here to See the Profile for FASTFORD   Click Here to Email FASTFORD     Edit/Delete Message   Reply w/Quote
I have a '67 coupe with a 4bbl 289. First off, what kind of gas mileage should I be getting now?
My second question is how much gas mileage will I lose if I install GT40 cylinder heads...and how much hp gain will I get?
Please Reply...Thanks

IP: Logged

Fastymz
Moderator

Posts: 12015
From: Reno Nv USA MEM#1240
Registered: Apr 2001

posted 09-16-2002 05:40 PM     Click Here to See the Profile for Fastymz   Click Here to Email Fastymz     Edit/Delete Message   Reply w/Quote
What trans are you using and what rear gears do have.What shape is the motor in,and what carb do you have.

SCOOP

------------------

2.634 60's
[email protected] 1/8 mile

65 coupe,351w,C4,Big Boss 429 hood scoop,8"3.40 TracLoc,Cragar SS,Black Suede.

https://mustangsandmore.com/ubb/Fastymz.html

IP: Logged

FASTFORD
Gearhead

Posts: 105
From: USA
Registered: Aug 2002

posted 09-16-2002 05:47 PM     Click Here to See the Profile for FASTFORD   Click Here to Email FASTFORD     Edit/Delete Message   Reply w/Quote
I have a c-4 with 2.79:1 gears (soon to be 3.27:1), recently rebuilt engine, and 600 cfm holley

IP: Logged

Fastymz
Moderator

Posts: 12015
From: Reno Nv USA MEM#1240
Registered: Apr 2001

posted 09-16-2002 05:52 PM     Click Here to See the Profile for Fastymz   Click Here to Email Fastymz     Edit/Delete Message   Reply w/Quote
I'd say you should get 15-18mpg if you keep your foot out of it.
And for the GT heads I've read they are good for 20-30hp.And they should hurt milage at all.

SCOOP

------------------

2.634 60's
[email protected] 1/8 mile

65 coupe,351w,C4,Big Boss 429 hood scoop,8"3.40 TracLoc,Cragar SS,Black Suede.

https://mustangsandmore.com/ubb/Fastymz.html

IP: Logged

mustangs68
Moderator

Posts: 18183
From: Hampton,Virginia,USA MCA#39406 M&M #12
Registered: May 99

posted 09-16-2002 06:00 PM     Click Here to See the Profile for mustangs68   Click Here to Email mustangs68     Edit/Delete Message   Reply w/Quote
I measure my gas milage by the year
sam

IP: Logged

indyphil
Gearhead

Posts: 877
From: Lafayette, IN, USA
Registered: Jul 2002

posted 09-17-2002 08:35 AM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
I have a 68 289 with 2 barrel carb, 2.79 rear end and c-4. I got about 22-25 mpg at 70mph highway cruising. Since then I have richened the carb up a little so Maybe I get 20-22 now. I would guess if everything is running sweetly that you should get 18mpg on the highway with that 4 barrel depending on how rich you run it.

You shouldnt hurt gas mileage with heads, sometimes headers and other perf mods can actually help gas mileage if you leave the carb alone.

The 3.27 rear will hurt gas mileage a lot more than the heads

IP: Logged

V8 Thumper
Gearhead

Posts: 3529
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 09-17-2002 08:58 AM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
My '289' gets 9-10 mpg

IP: Logged

Pierre
Gearhead

Posts: 366
From: France
Registered: Apr 2002

posted 09-17-2002 09:05 AM     Click Here to See the Profile for Pierre   Click Here to Email Pierre     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by V8 Thumper:
My '289' gets 9-10 mpg

Did you forget your drain plug or do you floor it at every light ?

I would be curious (if this is not classified info ) to see your engine set-up

IP: Logged

V8 Thumper
Gearhead

Posts: 3529
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 09-17-2002 09:49 AM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Pierre:
Did you forget your drain plug or do you floor it at every light ?


LOL No, and yes

Pierre, here I am goofing around, and I'm late for work , I gotta go I'll post some specs and pics soon. Hint: not exactally two hundred eighty nine cubic inches any more

[This message has been edited by V8 Thumper (edited 09-17-2002).]

IP: Logged

mustangs68
Moderator

Posts: 18183
From: Hampton,Virginia,USA MCA#39406 M&M #12
Registered: May 99

posted 09-17-2002 12:54 PM     Click Here to See the Profile for mustangs68   Click Here to Email mustangs68     Edit/Delete Message   Reply w/Quote
seriously mine get about 10-12
sam

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2003, Steve LaRiviere. All Rights Reserved.


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Build a free Mustangsandmore.ws Home Page!]

[About M&M][Acronyms][Calendar][Chat][Classifieds] [Members' Pics] [M&M Mug Shots]

[ Mustangsandmore.com Bookstore] [Mustangsandmore.com T-Shirts][Tech Articles]