NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > Land Use / Off Topic and other Forums > Non-Tech / Off Topic
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

Non-Tech / Off Topic The popular Non-Tech Forum. NO SPAM at all. Period.

Thread Tools Rate Thread Display Modes
Old September 17th, 2012, 17:09
AIbandit's Avatar
AIbandit AIbandit is offline
NAXJA Member
Join Date: Nov 2005
Location: Chico, CA
Posts: 5,762
uphill gas mileage and engine displacement

So we all know small engine's struggle more up hill, but is there a point where a v8(20mpg ish) is more efficient than a 4cyl(40mpg ish).
87 XJ 2door, 4.6L, aw4, Atlas 2, D60 ARB , 10.5 Detroit, 5.38's, 41" Iroks, 14" swayaway CO
88 MJ Chief, 4.0 Ax15, Fulltraction long arm, D30, D44, 33's
Reply With Quote
Old September 18th, 2012, 08:33
JohnX's Avatar
JohnX JohnX is offline
Sarge <3 Ben
Join Date: Nov 2004
Location: Rancho Cucamonga CA
Posts: 9,642
Re: uphill gas mileage and engine displacement

I don't believe there is that point on the highway. Someone can feel free to correct me, but it takes a defined amount of power to move a defined amount of weight up a hill. So for any given situation in like vehicles, the four cylinder is likely to have enough power to move the truck up the hill, where as the v8 will likely always have an excess amount of power. Even if the 4 banger doesn't have enough power, the truck slows down, changes gears, or whatever.

That would be for highway type driving of course, the power required to accelrate the vehicle to a given speed could easily be more than the 4 cylinder can handle, so it would be working at peak output for much longer than the v8 to achieve the same speed. Depending on the number of stop and go's in a given trip, the overworked four cylinder can get worse mileage.

This is all my 20 seconds of thought, so who knows?
Praise Marty Moose!
Reply With Quote
Old September 19th, 2012, 16:05
alex22's Avatar
alex22 alex22 is offline
NAXJA Forum User
Join Date: Oct 2007
Location: CT: waterbury area
Posts: 1,432
Re: uphill gas mileage and engine displacement

I think you will need to find the specific fuel consumptions of the v8 at X RPM needed to maintain a given speed and the 4 cyl at Y RPM needed to maintain the same speed.

I see what you're getting at, the MPG of a v8 at 2000 RPM vs a 4 cyl at 3500 RPM (random made up numbers.)

Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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 Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
replacement for discontinued Valvoline High Mileage engine oil the_bandit87 OEM Tech Discussion 11 June 25th, 2008 06:58
High mileage engine replacement? Muddy Beast OEM Tech Discussion 10 May 22nd, 2008 17:31
Extreme displacement OBA RCP Phx Modified Tech Discussion 2 April 30th, 2008 03:19
WTB VW/Small Displacement Diesel BBeach NAC Classifieds 2 December 4th, 2007 19:45
Sanden A/C compressor displacement Capt. Nemo OEM Tech Discussion 4 May 1st, 2005 20:28

All times are GMT -7. The time now is 10:25.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014