horsepower - Page 2 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Liberty Forums > KK Liberty Forum > horsepower

Engo LED Flush Mount Lights *PAIR* Flood or Spot 1,600 LumYukon Ultimate 35 axle kit for c/clip axles with Yukon ZipRockridge 4WD IS Taking Zone Offroad Suspension Lift Kits

Reply
Unread 12-09-2012, 09:57 AM   #16
jonrjen
Registered User
2011 KK Liberty 
 
Join Date: Apr 2010
Location: Texas
Posts: 1,077
[quote=az16339;14578384]
Quote:
Originally Posted by jonrjen;13603275)Now for the exhaust, I have always believed that the only thing the aftermarket exhaust will do is add noise. And that an aftermarket exhaust offers no real benifit other than to free up the flow of pressure. However, I did install the JBA exhaust and my only expectations were more noise and a bright stainless exhaust tip. But for some reason my in town mileage has gone up 3 MPG and acceleration has improved both from a dead standstill and in on line acceleration IE: passing. The MPG increase is based off of readings from my ScanGauge, the acceleration is a pure "Seat of the Pants" feel. Even my wife has noticed the acceleration difference. So for $149 the exhaust was the best bang for the buck I have ever purchased for any vehicle./QUOTE

What does installation of the JBA exhaust do to a Chrysler extended warranty?
All my 2011 Liberty has is the standard warranty, no extended policy. the only change should be that the warranty will no longer cover the exhaust from the cat back. All it basicly did was free up the exhaust and do away with the rear resonator making it a little louder.
Personally I like the big stainless exhaust tip, the improved mpg is a bonus to me.

__________________
"If you have a difficult job to do....Give it to a lazy man....He'll find the easy way to do it."
jonrjen is offline   Reply With Quote Quick reply to this message
Unread 12-09-2012, 01:57 PM   #17
Wearyman
Registered User
2008 KK Liberty 
 
Join Date: Sep 2011
Location: Buffalo, New York
Posts: 141
The only way to reliably improve the fuel efficiency of your Liberty is to shell out the big bucks to have the gasoline engine removed and replaced with CRD. That will get you huge mileage improvements. Of course, you'll burn all the money you would save in fuel costs by replacing the engine, but hey, at least you can say you have a more efficient engine!

In all seriousness, I do wonder if anyone has looked into a dual-fuel LPG/Gas conversion? Compared to a full engine replacement an LPG conversion is MUCH less expensive, around $1500, vs 5-10 grand for an engine replacement. I just don't know if there are any "50 state legal" kits for fuel injected vehicles yet. I KNOW there are "Farm vehicle" kits that would work on the Liberty engine, but I don't know about street legal ones.

The only reason I ask is that LPG only slightly less efficient to run than gasoline (around 15% less) but costs MUCH less per gallon (about half at current rates). Since it isn't pressurized like CNG it is much safer to use in an offroad vehicle. If you rip open the tank on a rock you just cut off the engine and allow 10 min or so for the vapor to dissipate, then swap back to gasoline for the rest of your trip. Even better, they can use "toroidal" tanks that fit in the spare slot, so they could be permanently mounted in a hidden location without giving up cabin storage. Assuming you can find another spot for your spare, of course.

Has anyone tried this or know anyone that has tried it?
Wearyman is offline   Reply With Quote Quick reply to this message
Unread 12-09-2012, 02:15 PM   #18
jonrjen
Registered User
2011 KK Liberty 
 
Join Date: Apr 2010
Location: Texas
Posts: 1,077
If I recall, when running on LP you also loose HP/TQ. Then add in the weight of the LP tank and LP and the HP you were looking for is now a total loss. And I'm not sure the extended fill up range or cost of the conversion would be worth the investment.

I know that when I purchsed my Liberty I wasn't expecting HP, TQ or MPG and it hasn't let me down yet. I was expecting a vehicle I could tow back of the motorhome, room for the grandkids, handle snow/ice/mud when needed, be safe for the family and it hasn't let me down yet.
__________________
"If you have a difficult job to do....Give it to a lazy man....He'll find the easy way to do it."
jonrjen is offline   Reply With Quote Quick reply to this message
Unread 12-09-2012, 03:22 PM   #19
Wearyman
Registered User
2008 KK Liberty 
 
Join Date: Sep 2011
Location: Buffalo, New York
Posts: 141
Quote:
Originally Posted by jonrjen View Post
If I recall, when running on LP you also loose HP/TQ. Then add in the weight of the LP tank and LP and the HP you were looking for is now a total loss. And I'm not sure the extended fill up range or cost of the conversion would be worth the investment.

I know that when I purchsed my Liberty I wasn't expecting HP, TQ or MPG and it hasn't let me down yet. I was expecting a vehicle I could tow back of the motorhome, room for the grandkids, handle snow/ice/mud when needed, be safe for the family and it hasn't let me down yet.
I'm not aware of any significant loss of horsepower or torque when using LPG. I know you lose some efficiency, but that's about it. Horsepower and Torque is derived from the engine and gearing, not strictly the fuel the engine burns.

Diesels have more torque not because of the diesel fuel itself, but because of the manner in which it must be burned (high compression ratio that requires heavier components with more inertia). Due to this, diesel engines naturally produce much more power and torque than gasoline ones of comparable size.

LPG doesn't change the fundamentals of a gasoline engine, it just needs to be mixed slightly differently than gasoline, thus the special fuel injection module or carburetor. Other than that, the available torque and power should be roughly the same per stroke. You just need to burn a bit more LPG than gasoline to get to the same point, thus the efficiency loss.

At least, that's my understanding of it anyway.
Wearyman is offline   Reply With Quote Quick reply to this message
Unread 12-09-2012, 05:36 PM   #20
tjkj2002
Registered User
2002 KJ Liberty 
 
Join Date: Dec 2009
Location: Colorado
Posts: 8,114
Quote:
Originally Posted by Wearyman View Post
Diesels have more torque not because of the diesel fuel itself,.
Actually the majority is from the fuel burned.Diesel has more BTU's then gas,meaning it has more potential energy(or stored energy) then gas.

The added compression needed to ignite the diesel is where the heavier contruction comes into play,does add some low end torque but not as much as you think.More low end torque can be achieved in any engine by increasing the stroke.There are 3 basic engine types for where you want to make your torque and they are "squared engine","under squared",and "over squared".A squared engine means the bore and stroke are identical(or very close) and is a good power producer in both the low and high rpm's.Under squared engines have a larger bore then stroke and are high rpm engines,and of course over squared means the stroke is much greater then the bore to produce more low end power.All diesels are over squared engines.
__________________
'02 Liberty sitting on 35" tires,HP44,RockJock60,and AtlasII t-case
tjkj2002 is offline   Reply With Quote Quick reply to this message
Unread 12-09-2012, 07:35 PM   #21
streetglideok
Registered User
2005 KJ Liberty 
 
Join Date: Jul 2011
Location: Colorado Springs, Colorado
Posts: 2,415
Yep, longer stroked engines give the pistons more leverage against the crankshaft, plus the greater BTU of diesel fuel vs gas, and the direct injection, it makes more power. Though on the other side of the coin, the newer DI gas engines do see very nice increases in torque, and horsepower, and better fuel mileage to boot, and just like diesels, they really like forced induction. Regardless, diesels have an edge in making power. Only issue is, they make their power at a much lower RPM band than gas engines do, and that affects the horsepower numbers. That, in itself really confuses people, because the majority of people do not understand what horsepower really is, and that it is a unit of measurement of power output over time and RPMs. Torque is the actual power measurement of the engine.
streetglideok 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 JeepForum.com 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 e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.