Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
Sign in using an external account
Register Forgot Password?


1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 09-22-2010, 03:17 PM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Gas mileage difference C6 vs 4-speed

Can anyone who has done a C6 to 4-speed manual trans conversion, tell me the gas mileage difference they got after the swap? Any engine but particularly 351w.
Thanks
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #2  
Old 09-22-2010, 05:57 PM
bashby's Avatar
bashby bashby is offline
Post Fiend
 
Join Date: Nov 2005
Location: Charles Town, W bygod Va
Posts: 6,084
bashby has a great reputation on FTE.bashby has a great reputation on FTE.bashby has a great reputation on FTE.bashby has a great reputation on FTE.bashby has a great reputation on FTE.
Are you talking about an OD 4 speed? I've heard a C6 uses about 30 hp so you should see some improvement, even without OD.
__________________
92 F250 4x4 7.3idi zf5 3.55's Meyer plow
86 F350 2wd C&C Dump 351w C6 4.10s Meyer plow
The rest of my signature changed as to not offend some liberal crybaby.
Reply With Quote
  #3  
Old 09-23-2010, 01:53 AM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
No, not an OD 4-spd - just a straight 1:1 top gear trans......T18, NP435 etc.

I've read a few times, somewhere, that a C6 uses up to 65hp.

But I'd like to hear of the experience on both mileage & power, of anyone who had done a C6/4spd swap, in either direction.
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #4  
Old 09-25-2010, 02:15 PM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Anyone able to help?
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #5  
Old 09-25-2010, 02:53 PM
Franklin2's Avatar
Franklin2 Franklin2 is online now
Moderator
 
Join Date: Jan 2001
Location: Staunton VA
Posts: 33,043
Franklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant future
I don't have any experience with swapping a c6 with a 4 speed. I did swap a c6 for a zf 5 speed(which has overdrive) and gained 3mpg. So I would assume the 4 speed would be something less than 3mpg.

I find it hard to believe that the c6 would soak up 65hp, since most of these old v8's didn't make much over 150hp(302, 351w) and that would be almost half the power output of the engine.

I would guess you might see 1-2mpg increase. If you look at all the old car and truck EPA specs, the auto loses about 1-2mpg to the manual correct?
__________________
Dave F

1989 F250 XLT Diesel
Reply With Quote
  #6  
Old 09-25-2010, 03:00 PM
PaulzF150 PaulzF150 is offline
Senior User
 
Join Date: Jun 2002
Location: Chandler,Arizona - USA
Posts: 330
PaulzF150 is starting off with a positive reputation.
I've had 2 of these trucks, both with the I-6. The first one, an '83, had a 2.47 rear and a 3 on the tree. The one I have now, an '85, has the C6 and a 3.55 rear. The '83 used to get as much as 22 mpg on the highway. My '85 gets about 13. At 65-70, the '85 is churning at 3000 rpms. Generally, especially with these older trucks, you get better gas mileage from a standard shift that you would an automatic. Also keep in mind that your 351 will probably not rev as high as an I6 at 70 mph, due to the extra power. Frankly, I would go with the standard shift. Hope this helps.
Reply With Quote
  #7  
Old 09-25-2010, 09:47 PM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Thanks for the replies.

I don't know exactly how the hp usage is worked out - it can't be a constant, so maybe the highest loss isn't until full-on at 5-6000 rpm?
The more I dig, the more the 60ish hp figure comes up. And around 15hp for the 4 speed transmissions.
And yet one guy with 302 in an older F1, swapped from a 4spd to a C6, & said he couldn't notice any power loss driving..........he wasn't sure on his mileage.
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #8  
Old 09-25-2010, 11:46 PM
fordsgofaster's Avatar
fordsgofaster fordsgofaster is offline
Senior User
 
Join Date: Jul 2009
Location: Australia
Posts: 100
fordsgofaster is starting off with a positive reputation.
I can't help much either but I'm fairly confident that the 55 - 60 hp loss is from drag racing guys comparisons & their most likely pulling down 500- 700hp or so on the dyno. I doubt the drag at cruise would be as hugely significant.

I have no doubt it probably does take some more turning at cruise than a t18 have no idea how much but my truck has a c6 & its not like you can feel it pulling the motor down at cruise or anything I average 11.7MPG absolutely loaded to the hilt. don't know what it dose unloaded it nearly never is.
__________________
----------------------------------------------------
Ford Australia spec 1982 F100 4X4

351 cleveland, C6, NP208, dana44/9" 3.5:1.
Carter Thermoquad, bosh eletrics, RHD
Reply With Quote
  #9  
Old 09-26-2010, 04:14 AM
PaulzF150 PaulzF150 is offline
Senior User
 
Join Date: Jun 2002
Location: Chandler,Arizona - USA
Posts: 330
PaulzF150 is starting off with a positive reputation.
Ken, A little off topic....but I really like the picture of your truck. I am looking to repaint mine, which is the same color, but different 2-tone style than yours. I like the two tone style of your truck better. Would you be able to create an album of your truck. I want to see how your tailgate is painted. Thanks.
Reply With Quote
  #10  
Old 09-26-2010, 04:45 AM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
No trouble, Paul - just might take a couple of days
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #11  
Old 09-26-2010, 02:19 PM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Thanks, fordsgofaster - is that imperial gallons?
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #12  
Old 09-26-2010, 02:26 PM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Paul,
I've added some photos showing the tailgate to my existing album '83 F250 XLT' (via my public profile), that were sent to me by the trucks previous owner when I was looking at buying it.
Let me know, I can take some better quality ones if you would like.
Ken
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #13  
Old 09-26-2010, 03:22 PM
Diesel_Brad's Avatar
Diesel_Brad Diesel_Brad is offline
Post Fiend
 
Join Date: May 2009
Location: Gilbert, PA
Posts: 13,853
Diesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud of
The C6 has no lock up torque convertor so it will be spinning a couple hundered RPMs more than the 4 speed manual in top gear. Other than that i really cant see milage loss while cruising
__________________
Looking for Blue 40-20-40 seats. PM me !!!
Reply With Quote
  #14  
Old 09-27-2010, 03:15 AM
Ken Blythen's Avatar
Ken Blythen Ken Blythen is offline
Posting Guru
 
Join Date: Aug 2007
Location: New Zealand
Posts: 1,810
Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.Ken Blythen has a good reputation on FTE.
Quote:
Originally Posted by Franklin2 View Post
I don't have any experience with swapping a c6 with a 4 speed. I did swap a c6 for a zf 5 speed(which has overdrive) and gained 3mpg
Dave - was that in your diesel, or a gas-engine truck?
__________________
1983 F250 XLT 2WD, 351W, T19, 3.54 D60
1942 GMC 6x4
Reply With Quote
  #15  
Old 09-27-2010, 05:59 PM
fordsgofaster's Avatar
fordsgofaster fordsgofaster is offline
Senior User
 
Join Date: Jul 2009
Location: Australia
Posts: 100
fordsgofaster is starting off with a positive reputation.
Quote:
Originally Posted by Ken Blythen View Post
Thanks, fordsgofaster - is that imperial gallons?
To be honest I'm not sure, I used a conversion calculator on the net to convert it & I don't remember which one.

Our speed zones & such are in metric here so we also talk metric figures for fuel consumption. It uses 1liter per 5 kilometers, what we call 5 kays per liter. I forgot to I run 3:5 diff gears for economy reasons, acts like an overdrive so my figures won't be comparable anyways.
__________________
----------------------------------------------------
Ford Australia spec 1982 F100 4X4

351 cleveland, C6, NP208, dana44/9" 3.5:1.
Carter Thermoquad, bosh eletrics, RHD
Reply With Quote
Old 09-27-2010, 05:59 PM
 
 
 
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
C6 vs manual 4 spd gas mileage Ken Blythen 1973 - 1979 F-100 & Larger F-Series Trucks 7 09-27-2010 04:17 PM
C6 vs manual 4 spd gas mileage Ken Blythen Clutch, Transmission, Differential, Axle & Transfer Case 4 09-27-2010 03:05 AM
gas mileage difference np203 to np205 havi Clutch, Transmission, Differential, Axle & Transfer Case 2 09-09-2007 01:00 PM
Gas Mileage and Trannys WillyB Ford Inline Six, 200, 250, 4.9L / 300 27 07-10-2006 12:33 PM
6 cylinder vs V-8 dantheman1963 1987 - 1996 F150 & Larger F-Series Trucks 36 05-17-2004 07:21 PM


Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks

Tags
1988, 400, 4speed, c6, convert, converting, deisel, f250, ford, gas, manual, mileage, mpg, np435, speed

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump



All times are GMT -5. The time now is 10:59 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup