Raising speed limits - Page 4 - Pirate4x4.Com : 4x4 and Off-Road Forum
 
Pirate4x4.Com : 4x4 and Off-Road Forum  

Go Back   Pirate4x4.Com : 4x4 and Off-Road Forum > Miscellaneous > General Chit-Chat
Notices

Reply
 
Share LinkBack Thread Tools Display Modes
Old 05-16-2019, 06:55 AM   #76 (permalink)
Registered User
 
Join Date: Feb 2007
Member # 86724
Posts: 29,676
Quote:
Originally Posted by [486] View Post
start changing things, it's real easy to set up the maps wrong in spots, end up with little islands of just barely lean enough to run (8-9:1 afrs)
it's a factory BMW set of parameters

I changed the intake manifold to a 330 piece and put factory BMW 130 software in the DME. The only difference between a 325/328/330 in this generation is the manifold and the software. I wanted that extra 40 HP. They never offered a 330 in a wagon chassis in north america, only 325s and 328s.
__________________
Electricity is really just organized lightning.
87manche is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 08:22 AM   #77 (permalink)
Registered User
 
Join Date: Jan 2007
Member # 85483
Posts: 23,312
Quote:
Originally Posted by [email protected] View Post
There's something wrong with your car unless it's a truck. I don't know what car you have, if the engine is heavily modified, or what the coast down curve looks like, but if it's getting 8mpg at 65mph you'd better be grossing 20,000lbs, even on e85. I'd start there.

There's no getting around physics, it's going to take around twice the power to push a vehicle at 85mph as 65mph. Google some typical SI engine bsfc maps (or better yet pick up a copy of heywood) and look at how implausible it would be for an engine to use 20% less fuel to make twice the horsepower anywhere near road load conditions. Unless of course it was tuned really badly or the gearing was way off for street use. Could also be fuel leaking out onto the ground at a constant rate, making your MPG look better with higher ground speeds.
There is such thing as optimum rpm for engine efficiency...that could be 55mph with a 3 speed automatic with the certain differential gearing/tire size and it maybe 70 with a 6 speed.

I know for a fact that setting the cruise at 70 mph in my old 92 F150 I got 15 mpg and at 55 it got 13. And no, there wasn't a damn thing wrong with it.
__________________
Today, truth has been forced to take a back seat to political correctness
thumping is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 09:15 AM   #78 (permalink)
Registered User
 
Join Date: Sep 2010
Member # 168716
Location: Louisville-Southern Indiana
Posts: 170
Quote:
Originally Posted by 87manche View Post
did yo ubother reading the article?


and my car gets better fuel mileage at 70 than it does at 55.

because double OD 6 speed.
Agreed my DD hates running 55. 70-80 is its sweet spot for mileage and trans not hunting for gears. IN just recently raised the limits from 55 to 60 65 70 around metro Louisville which basically made it legal to drive the speeds everyone was already driving. Traffic flows noticeably better in a few spots though.
scottmk5 is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 09:18 AM   #79 (permalink)
Change is good.
 
Roc Doc's Avatar
 
Join Date: Jun 2003
Member # 20631
Location: Desert Hills, AZ
Posts: 35,093
Quote:
Originally Posted by Overbear View Post
Since we used my car as the example, lets go with that...

So, Same road, same drive, same lack of traffic, start with same full tank, no change in tune, same % of E85. 65mph I get exactly 8mpg, run it up and keep it at 85, and I now get 10mpg.

I will wait while you try to explain that.
We'll make this a multiple choice test, since you obviously can't prove your work.

A. You don't know how to accurately calculate fuel usage.
B. You're a liar.
C. All of the above.
__________________
Quote:
I get adds for ghey cruises.....
Anyone else????
Roc Doc is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 09:29 AM   #80 (permalink)
Non-Lemming
 
SanDiegoCJ's Avatar
 
Join Date: May 2000
Member # 840
Location: Ramona, SoCal
Posts: 78,476
Quote:
Originally Posted by Roc Doc View Post
We'll make this a multiple choice test, since you obviously can't prove your work.

A. You don't know how to accurately calculate fuel usage.
B. You're a liar.
C. All of the above.
Yup.
__________________
One of the great achievements of science has been, if not to make it impossible for intelligent people to be religious, then at least to make it possible for them not to be religious. We should not retreat from this accomplishment.

Quote:
Salesmen and women. God sells to the ignorant.
SanDiegoCJ is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 09:46 AM   #81 (permalink)
Change is good.
 
Roc Doc's Avatar
 
Join Date: Jun 2003
Member # 20631
Location: Desert Hills, AZ
Posts: 35,093
Oh, and in before Butchbear claims everyone is the stupidist mutherfucker on PBB, and his magic Lesbaroo cheats the laws of physics.
__________________
Quote:
I get adds for ghey cruises.....
Anyone else????
Roc Doc is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 11:12 AM   #82 (permalink)
Registered User
 
Join Date: Oct 2001
Member # 7772
Posts: 68
Quote:
Originally Posted by 87manche View Post
I do what I want. You should try it some time.
Where is this magical world where you do what you want? That world doesn't exist for me, Poncho. My world is other people thinking I have something to prove to them. You should try it sometime.

Quote:
Originally Posted by 87manche View Post

I am not aggressive. Far from it actually. I am courteous, I let people zipper merge, I don't tailgate, I always use my signals.


That doesn't work for me. People decided ramming me with cars was a good motivational tool. Obviously, as you can tell from my attitude, that wasn't an effective strategy.

Life's unfair, suck it up.
EverNoob is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 11:17 AM   #83 (permalink)
Registered User
 
Join Date: Dec 2004
Member # 40417
Location: Surprise, AZ
Posts: 12,452
Some funny shit up in here
__________________
Better to be a racer for a moment, than a spectator for a lifetime. Looking for a clean LX Foxbody.
FlexyTJ is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 11:21 AM   #84 (permalink)
Registered User
 
Join Date: Feb 2007
Member # 86724
Posts: 29,676
Quote:
Originally Posted by EverNoob View Post
Where is this magical world where you do what you want? That world doesn't exist for me, Poncho. My world is other people thinking I have something to prove to them. You should try it sometime.





That doesn't work for me. People decided ramming me with cars was a good motivational tool. Obviously, as you can tell from my attitude, that wasn't an effective strategy.

Life's unfair, suck it up.
I'm not sure why you think I think life is unfair?

you're the one that engaged me, not the other way round.

I guess you'll just go back on the ignore list since you continue to make absolutely no fucking sense.
__________________
Electricity is really just organized lightning.
87manche is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 12:59 PM   #85 (permalink)
Oh Jesus Tits....
 
Join Date: Mar 2003
Member # 17554
Location: Mesa, AZ
Posts: 2,656
Quote:
Originally Posted by EverNoob View Post


I love people complaining about truckers as they rush to the mall to buy stuff.
My consumer habits have nothing to do with some non English speaking trucker driving like a douche. If they stay in the right lane on hills I'll still get all the made in china shit I'll ever need.

__________________
1977 Ford F150 4x4 Shorty 351M/NP435
2007 Ram 2500 Quad Cab 4x4 5.9 Cummins
D-RAT is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 04:07 PM   #86 (permalink)
Registered User
 
Join Date: Sep 2000
Member # 1792
Location: Parachute,CO
Posts: 4,098
Quote:
Originally Posted by arse_sidewards View Post
Screw off grandpa. Nobody is forcing you to go that fast. The people that want to go that fast on a rural highway should be able to.
I grew up in the U.P. I know the roads. I have driven them as fast as I could. I also had many a close call. I probably should have died back then. Dumb luck saved me I guess. Most idiots can't drive the current speed limits as it is. NO ONE pays the fuck attention.
My uncle owned a junkyard on US 41. The nasty accidents he had to go recieve would make anyone think twice. Like the pick up that we had to bring out of the woods piece by piece, along with parts of the guy. That was on M95 a 55mph hiway.
__________________
CJJuggy.FI406/465/205/D60/14bolt FF on 39.5 Swampers.Kid's '70 Jeepster D44/14bolt FF.
Cheepin is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 06:16 PM   #87 (permalink)
Registered User
 
Join Date: Mar 2011
Member # 184924
Location: Downey, Id
Posts: 80
Quote:
Originally Posted by Cheepin View Post
I grew up in the U.P. I know the roads. I have driven them as fast as I could. I also had many a close call. I probably should have died back then. Dumb luck saved me I guess. Most idiots can't drive the current speed limits as it is. NO ONE pays the fuck attention.
My uncle owned a junkyard on US 41. The nasty accidents he had to go recieve would make anyone think twice. Like the pick up that we had to bring out of the woods piece by piece, along with parts of the guy. That was on M95 a 55mph hiway.
Never mind most of those accidents were drunks or tired people or people swerving to avoid slow people like you right? I hate old fuckers and thier "listen here sonny I know because blank bullshit..."
__________________
69 SS/RS Camaro 396 450 hp, 2007 Ram 3500 4x4,
mikenike is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 07:06 PM   #88 (permalink)
Registered User
 
Join Date: Feb 2007
Member # 86724
Posts: 29,676
Quote:
Originally Posted by Cheepin View Post
I grew up in the U.P. I know the roads. I have driven them as fast as I could. I also had many a close call. I probably should have died back then. Dumb luck saved me I guess. Most idiots can't drive the current speed limits as it is. NO ONE pays the fuck attention.
My uncle owned a junkyard on US 41. The nasty accidents he had to go recieve would make anyone think twice. Like the pick up that we had to bring out of the woods piece by piece, along with parts of the guy. That was on M95 a 55mph hiway.
was it a single car accident?
was only the driver of the truck killed?


no fucks given then. He didn't hurt anyone else with his decision.

you can die any day on the highways of this country, and it's probably not because someone was speeding.
__________________
Electricity is really just organized lightning.
87manche is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 07:17 PM   #89 (permalink)
Custom User Title
 
Provience's Avatar
 
Join Date: Jul 2009
Member # 138976
Location: Thurston County, WA
Posts: 28,424
Quote:
Originally Posted by Overbear View Post
Since we used my car as the example, lets go with that...

So, Same road, same drive, same lack of traffic, start with same full tank, no change in tune, same % of E85. 65mph I get exactly 8mpg, run it up and keep it at 85, and I now get 10mpg.

I will wait while you try to explain that.
haven't read this whole thread, but that is because you have too much motor for the load.

you would be way more efficient at 55mph with something making half or a third the power
__________________
up is difficult, down is dangerous

freedom of choice is what you have, freedom from choice is what you want

keep your head down, go to sleep to the rhythm of the war drums
Provience is offline   Reply With Quote Quick reply to this message
Old 05-16-2019, 11:28 PM   #90 (permalink)
Registered User
 
Join Date: Dec 2004
Member # 40417
Location: Surprise, AZ
Posts: 12,452
Quote:
Originally Posted by Provience View Post
haven't read this whole thread, but that is because you have too much motor for the load.
wat?

It just means his tune sucks or there is a hole in the gas tank
__________________
Better to be a racer for a moment, than a spectator for a lifetime. Looking for a clean LX Foxbody.
FlexyTJ is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 06:27 AM   #91 (permalink)
Registered User
 
Join Date: Jan 2007
Member # 85483
Posts: 23,312
Quote:
Originally Posted by Provience View Post
haven't read this whole thread, but that is because you have too much motor for the load.

you would be way more efficient at 55mph with something making half or a third the power
Well....I guess we should all be running a 5hp briggs... Just think how efficient we could be.
__________________
Today, truth has been forced to take a back seat to political correctness
thumping is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 06:35 AM   #92 (permalink)
Registered User
 
Join Date: Jun 2011
Member # 192237
Location: St. Paul, MN
Posts: 11,390
Quote:
Originally Posted by Provience View Post
haven't read this whole thread, but that is because you have too much motor for the load.

you would be way more efficient at 55mph with something making half or a third the power
no engine burns less fuel by opening the throttle plate further
[486] is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 09:07 AM   #93 (permalink)
Registered User
 
Join Date: Dec 2004
Member # 40417
Location: Surprise, AZ
Posts: 12,452
Quote:
Originally Posted by [486] View Post
no engine burns less fuel by opening the throttle plate further
^^This. and NO engine burns less fuel with an increased aero load (higher speed). But those two facts seem irrelevant here
__________________
Better to be a racer for a moment, than a spectator for a lifetime. Looking for a clean LX Foxbody.
FlexyTJ is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 09:46 AM   #94 (permalink)
Registered User
 
paragon's Avatar
 
Join Date: Dec 2004
Member # 40266
Location: Jackson, MS USA
Posts: 24,068
Quote:
Originally Posted by [486] View Post
no engine burns less fuel by opening the throttle plate further
Quote:
Originally Posted by FlexyTJ View Post
^^This. and NO engine burns less fuel with an increased aero load (higher speed). But those two facts seem irrelevant here


fuel consumption is not the same thing as fuel economy.
__________________
[COLOR="Black"].

...
[/COLOR]
[CENTER][FONT="Franklin Gothic Medium"][SIZE="4"]"For God and country, Geronimo, Geronimo, Geronimo"[/SIZE][/FONT][/CENTER]
paragon is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 10:01 AM   #95 (permalink)
Custom User Title
 
Provience's Avatar
 
Join Date: Jul 2009
Member # 138976
Location: Thurston County, WA
Posts: 28,424
Quote:
Originally Posted by thumping View Post
Well....I guess we should all be running a 5hp briggs... Just think how efficient we could be.
Quote:
Originally Posted by [486] View Post
no engine burns less fuel by opening the throttle plate further
Quote:
Originally Posted by FlexyTJ View Post
^^This. and NO engine burns less fuel with an increased aero load (higher speed). But those two facts seem irrelevant here
brake specific fuel consumption.

the difference in fuel consumption for a 400hp engine to generate 50 hp to cruise at 55mph and 75 hp at 70 mph is low enough that the gain of 20mph is offset in consideration of gallons per mile used.

the same vehicle with a 75 hp engine operating at 100% open throttle would be, overall, much more efficient in the same package.

would it drive as well or pull a hill as well? no. Consider how a CVT or a prius hybrid drive is set to function.

lower inlet restriction equates directly to more optimum BSFC for all internal combustion engines and is part of why a diesel engine is inherently efficient compared to a gas engine, always operating at unrestricted air inlet.
__________________
up is difficult, down is dangerous

freedom of choice is what you have, freedom from choice is what you want

keep your head down, go to sleep to the rhythm of the war drums
Provience is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 10:01 AM   #96 (permalink)
Zeus of the Sluice
 
arse_sidewards's Avatar
 
Join Date: Feb 2013
Member # 256962
Location: People's Republic of Taxachusetts
Posts: 3,408
Quote:
Originally Posted by [486] View Post
no engine burns less fuel by opening the throttle plate further
I don't think you understand how EGR influences fuel economy.
arse_sidewards is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 10:10 AM   #97 (permalink)
Registered User
 
Join Date: Aug 2001
Member # 6234
Posts: 3,173
Peak volumetric efficiency is achieved at or near WOT. If it takes 30 HP to cruise at 70 mph and you can generate 30 HP at 2000 RPM at WOT vs. 30 HP at 3000 RPM at 50% throttle, you will use less fuel and therefore have better fuel economy at 2000 RPM.
WillyPete is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 10:17 AM   #98 (permalink)
Change is good.
 
Roc Doc's Avatar
 
Join Date: Jun 2003
Member # 20631
Location: Desert Hills, AZ
Posts: 35,093
Yeah, but will the plane take off or not?
__________________
Quote:
I get adds for ghey cruises.....
Anyone else????
Roc Doc is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 10:57 AM   #99 (permalink)
Registered User
 
Join Date: Dec 2004
Member # 40417
Location: Surprise, AZ
Posts: 12,452
Quote:
Originally Posted by WillyPete View Post
Peak volumetric efficiency is achieved at or near WOT. If it takes 30 HP to cruise at 70 mph and you can generate 30 HP at 2000 RPM at WOT vs. 30 HP at 3000 RPM at 50% throttle, you will use less fuel and therefore have better fuel economy at 2000 RPM.
The load is much higher in the first scenario. Load drives injector duty cycle, just as rpm does. The way a forced inducted vehicle behaves, especially one on E85, is drastically different than a N/A vehicle. We are ignoring too many important variables.

I think there is too much generalization going on to argue this. Everyone should post up a data log or two to prove their point.
__________________
Better to be a racer for a moment, than a spectator for a lifetime. Looking for a clean LX Foxbody.
FlexyTJ is offline   Reply With Quote Quick reply to this message
Old 05-17-2019, 11:00 AM   #100 (permalink)
Registered User
 
larboc@hotmail.com's Avatar
 
Join Date: Mar 2006
Member # 70148
Location: da U.P. of MI eh?
Posts: 6,219
Here is a generic bsfc map for a generic gas car engine with lines of constant power through it (no idea what each color represents, stole it from google images). Anyone here who is interested in what bsfc means should take a look. There is more than just "optimum speed" or "peak torque". BSFC is a measurement of thermal efficiency of the engine. Here, it's how many grams of fuel it takes to make a kWh of shaft energy.




You can see how far away from the middle you'd have to go to make double the power and use half the fuel in a reasonably normal vehicle.

VVT, externally cooled egr, AFM, and other technologies move the shape of the curves and make improvements, but nothing big enough to make some of the claims that have come up here valid.

Here's a generic google image stolen pic of power vs speed of some vehicles, no idea if the data is right but the shapes look plausible.

http://kilowatt-age.com/yahoo_site_a...4149_large.png

A fun experiment that anyone can do with a known vehicle weight and an obd logger is do a coast down curve and you can approximate your vehicle's relative power needs to maintain speeds and generate curve similar to that plot. Find a stretch of road that's flat, log the speed, and pop the trans in neutral. There's probably a phone app using GPS too.
__________________
I don't pay nothing for anything.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
larboc@hotmail.com is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Pirate4x4.Com : 4x4 and Off-Road Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.

** A VERIFICATION EMAIL IS SENT TO THIS ADDRESS TO COMPLETE REGISTRATION!! **

Email Address:
Insurance
Please select your insurance company (Optional)

Log-in


Thread Tools
Display Modes

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
4 speed vs 5 speed mpg ItsaVanMan Ford 18 02-04-2013 06:44 AM
Wanded Good 5 speed Toyota manual trans travelingtao Wanted! 1 01-17-2013 10:29 AM
Buggy: 2 or 4 speed t-case? kidkrawler General 4x4 Discussion 9 11-28-2012 11:05 AM


All times are GMT -7. The time now is 10:08 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 ©2011, Crawlability, Inc.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.