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Unread 04-01-2013, 11:29 AM   #16
flea1987
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2001 TJ Wrangler 
 
Join Date: Mar 2013
Location: temple, tx
Posts: 143
Quote:
Originally Posted by Siva283 View Post
Going to MPFI gives you about 30 more horsepower. Not just 3. Que89yj is getting ready to do it. I just sent him the parts from my old engine. He wouldnt do it just for 3 horsepower. Also with MPFI and 33x12.5 tires I am still getting about 17mpg on stock gears.
Ok, that's what I'll look into then, because if it'll run 33's with decent mileage I could keep my wife off my back about fuel economy and throw some 31's on her

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Unread 04-01-2013, 03:54 PM   #17
Xpress
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Quote:
Originally Posted by Siva283 View Post
Going to MPFI gives you about 30 more horsepower. Not just 3. Que89yj is getting ready to do it. I just sent him the parts from my old engine. He wouldnt do it just for 3 horsepower. Also with MPFI and 33x12.5 tires I am still getting about 17mpg on stock gears.
For a 4 cylinder?

Sorry, no, hate to burst your bubble but there's just no way you're going to get 30hp going from TBI to MPFI, otherwise everyone would be swapping to MPFI in the first place. The difference in HP output between the TBI and MPFI 2.5L engines is negligible.

http://en.wikipedia.org/wiki/AMC_straight-4_engine

http://www.jeepforum.com/forum/f12/y...-specs-563403/

http://www.allpar.com/mopar/amc-25.html

http://www.ehow.com/facts_7403148_je...fications.html

etc etc

The difference between the 2 different injection methods is maybe 10hp if you wind them out, otherwise the actual HP outputs in the RPM range the 2.5L engine is normally driven (between 2500 and 3500rpm) is between 3-5hp difference, not the 30 you claim it to be. As much as I hate to say it, but Que is wasting his time and money if he is expecting a 30hp gain just going to MPFI. This isn't a 4.2, it's already a pretty open flowing engine as is, that's why you can't get more HP out of it from bolting on a cold air intake, or an exhaust system. MPFI just adds in a bit of fuel efficiency (1-2mpg on a good day) and easier cold starts.
__________________
[URL="http://www.jeepforum.com/forum/f12/another-5-2l-yj-thread-1503048/"]My 5.2L Build thread[/URL]

-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
[QUOTE=mudsweatNgearz;21162729]Leave em off and weld an I beam on. Bumperetts just scream homo.[/QUOTE]
"A well regulated Militia, being necessary to the security of a free State, the [B][I]RIGHT[/I][/B] of the people to keep and bear Arms, [B][I]SHALL NOT BE INFRINGED[/I][/B]."
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Unread 04-02-2013, 05:56 AM   #18
Siva283
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Location: Falling Waters, WV
Posts: 3,698
Quote:
Originally Posted by Xpress View Post
For a 4 cylinder?

Sorry, no, hate to burst your bubble but there's just no way you're going to get 30hp going from TBI to MPFI, otherwise everyone would be swapping to MPFI in the first place. The difference in HP output between the TBI and MPFI 2.5L engines is negligible.

http://en.wikipedia.org/wiki/AMC_straight-4_engine

http://www.jeepforum.com/forum/f12/y...-specs-563403/

http://www.allpar.com/mopar/amc-25.html

http://www.ehow.com/facts_7403148_je...fications.html

etc etc

The difference between the 2 different injection methods is maybe 10hp if you wind them out, otherwise the actual HP outputs in the RPM range the 2.5L engine is normally driven (between 2500 and 3500rpm) is between 3-5hp difference, not the 30 you claim it to be. As much as I hate to say it, but Que is wasting his time and money if he is expecting a 30hp gain just going to MPFI. This isn't a 4.2, it's already a pretty open flowing engine as is, that's why you can't get more HP out of it from bolting on a cold air intake, or an exhaust system. MPFI just adds in a bit of fuel efficiency (1-2mpg on a good day) and easier cold starts.
I think you should go on a fact finding mission Mr. Self proclaimed Genuis. Its kinda like when you told that guy that our cooling systems have thermostats because they are so over engineered. Also since the wiring has to be redone and a new computer added unless you enjoy this type of thing even 30 horspower might not be worth it since for a little more work you could jump to the 4.0. With MPFI you get better fuel atomization and the cylinders tend to get the same amount of air fuel where this can vary widly in TBI. The power difference is very very noticable. 3 horsepower not so noticable.
__________________
1995 YJ. 2 inch BDS Spring lift. 1 inch shackle lift. 1.25 inch JKS Body Lift 33x12.5x15's. Engo 10,000 pound winch.

[QUOTE=Magnum;14117863] I gave the Jeep the required offering of $$, sweat, and blood, and everything works fine now. -- Jim[/QUOTE]

[QUOTE=ldso;16498409]. It started with a $200 axle, and a few thousand dollars later I was done :)[/QUOTE]

[QUOTE=Luuca;16122017]diagnose the real issue before you start going all Obama on it - spending mad cash you'll need for other important things.

Ask me how I know...[/QUOTE]

[QUOTE=Overhead;17658665]this is also my second set of RC springs this year. I'd rather spend the money again and get something that will last.[/QUOTE]
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Unread 04-02-2013, 06:08 AM   #19
Siva283
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According to your allpar link. The one from the manufacturer its at a 7 horsepower difference at 5000 and 5250 respectfully. I would much prefer a dyno sheet though as even numbers from the manufacturer are not always accurate. You can really feel the difference so I am inclined to believe the guy that works for Chrystler that has told me this over you.
__________________
1995 YJ. 2 inch BDS Spring lift. 1 inch shackle lift. 1.25 inch JKS Body Lift 33x12.5x15's. Engo 10,000 pound winch.

[QUOTE=Magnum;14117863] I gave the Jeep the required offering of $$, sweat, and blood, and everything works fine now. -- Jim[/QUOTE]

[QUOTE=ldso;16498409]. It started with a $200 axle, and a few thousand dollars later I was done :)[/QUOTE]

[QUOTE=Luuca;16122017]diagnose the real issue before you start going all Obama on it - spending mad cash you'll need for other important things.

Ask me how I know...[/QUOTE]

[QUOTE=Overhead;17658665]this is also my second set of RC springs this year. I'd rather spend the money again and get something that will last.[/QUOTE]
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Unread 04-02-2013, 10:18 AM   #20
Xpress
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You really in all honestly think the MPFI setup gives you 30hp over the TBI? Good luck with getting people to believe that one. You did not read what I wrote, you skimmed over it, hell bent on trying to get your point across:

Where we drive our 2.5L engines (lets be honest, who in their right mind winds a 2.5L out to 5200rpm? Nobody does, it doesn't make any more torque over 3200rpm), in the 2500-3500rpm range, the HP difference between the 2 engines is ~3-5hp, depending on the condition of your system. If the 2.5L MPFI was putting out 160hp there would be a LOT more people going to the 2.5L MPFI setup.

So why aren't people converting to 2.5L MPFI setups?

I'll save you the time.

It doesn't give you 30hp over TBI.

If you did your research, like I did, you would see that. But since you refuse to do it, and now you're looking like a fool, you're just going to sit there and try to get your invalidated point across.

Right from 4BangerJeep:

1984- 02 2.5L AMC

Applications: 1984- 88 CJ- 7, 1984- 00 XJ, 1987- 95 YJ, 1997- 03 TJ
Displacement: 151 cubic inches
Power Output: 105-125 hp (at) 4,000- 5,400 rpm
Torque Output: 125-150 lb- ft (at) 2,600- 3,200 rpm
Bore and Stroke: 3.88 x 3.19 inches
Compression Ratio: 9.2:1
Comments: 1984- 86 engines used a single-carburator (CJ-7 only).
1984- 90, TBI was available. Then in 1991, Multi-point Fuel Injection was introduced.
XJ's always had slightly higher performance numbers then the YJ.
1997, Jeep went with a different cam profile and new ECM.
This dropped the performance numbers but gave it a flat powerband.
Mopar Perfromance made many parts for the XJ and YJ, most can be used with later engines.
Since the last parts were made 10 years ago, there are no new ones to be had.
Many of the camshafts were dumped onto the eBay.com a few years ago.

Again, the power output between the 2 injection methods is negligible.

What we can summarize from all of this info is that:

TBI Gives you between 117-125hp at 5200rpm.

MPFI gives you 120-132hp at 5200rpm.

Not the 30hp difference you claim. The modern 2.4L I4 gives you around 150hp, but it is designed a lot better and more efficiently than the 2.5L.
__________________
[URL="http://www.jeepforum.com/forum/f12/another-5-2l-yj-thread-1503048/"]My 5.2L Build thread[/URL]

-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
[QUOTE=mudsweatNgearz;21162729]Leave em off and weld an I beam on. Bumperetts just scream homo.[/QUOTE]
"A well regulated Militia, being necessary to the security of a free State, the [B][I]RIGHT[/I][/B] of the people to keep and bear Arms, [B][I]SHALL NOT BE INFRINGED[/I][/B]."
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Unread 04-02-2013, 10:26 AM   #21
Siva283
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Posts: 3,698
I wind mine out when I am hung up in mud. I bet alot of others do also. I read the allpar one. The others are prone to to much error. I can easily see a 300 horsepower difference being possible. Plus like I said a will take a chrysler engineers word over yours anyday. Anyone that self proclaims they are a genus is not a reliable person in my experience. I also remember why I ignored you before. I guess I will place you back there.
__________________
1995 YJ. 2 inch BDS Spring lift. 1 inch shackle lift. 1.25 inch JKS Body Lift 33x12.5x15's. Engo 10,000 pound winch.

[QUOTE=Magnum;14117863] I gave the Jeep the required offering of $$, sweat, and blood, and everything works fine now. -- Jim[/QUOTE]

[QUOTE=ldso;16498409]. It started with a $200 axle, and a few thousand dollars later I was done :)[/QUOTE]

[QUOTE=Luuca;16122017]diagnose the real issue before you start going all Obama on it - spending mad cash you'll need for other important things.

Ask me how I know...[/QUOTE]

[QUOTE=Overhead;17658665]this is also my second set of RC springs this year. I'd rather spend the money again and get something that will last.[/QUOTE]
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Unread 04-02-2013, 10:28 AM   #22
Siva283
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Join Date: May 2011
Location: Falling Waters, WV
Posts: 3,698
Quote:
Originally Posted by Xpress View Post
You really in all honestly think the MPFI setup gives you 30hp over the TBI? Good luck with getting people to believe that one. You did not read what I wrote, you skimmed over it, hell bent on trying to get your point across:

Where we drive our 2.5L engines (lets be honest, who in their right mind winds a 2.5L out to 5200rpm? Nobody does, it doesn't make any more torque over 3200rpm), in the 2500-3500rpm range, the HP difference between the 2 engines is ~3-5hp, depending on the condition of your system. If the 2.5L MPFI was putting out 160hp there would be a LOT more people going to the 2.5L MPFI setup.

So why aren't people converting to 2.5L MPFI setups?

I'll save you the time.

It doesn't give you 30hp over TBI.

If you did your research, like I did, you would see that. But since you refuse to do it, and now you're looking like a fool, you're just going to sit there and try to get your invalidated point across.

Right from 4BangerJeep:

1984- 02 2.5L AMC

Applications: 1984- 88 CJ- 7, 1984- 00 XJ, 1987- 95 YJ, 1997- 03 TJ
Displacement: 151 cubic inches
Power Output: 105-125 hp (at) 4,000- 5,400 rpm
Torque Output: 125-150 lb- ft (at) 2,600- 3,200 rpm
Bore and Stroke: 3.88 x 3.19 inches
Compression Ratio: 9.2:1
Comments: 1984- 86 engines used a single-carburator (CJ-7 only).
1984- 90, TBI was available. Then in 1991, Multi-point Fuel Injection was introduced.
XJ's always had slightly higher performance numbers then the YJ.
1997, Jeep went with a different cam profile and new ECM.
This dropped the performance numbers but gave it a flat powerband.
Mopar Perfromance made many parts for the XJ and YJ, most can be used with later engines.
Since the last parts were made 10 years ago, there are no new ones to be had.
Many of the camshafts were dumped onto the eBay.com a few years ago.

Again, the power output between the 2 injection methods is negligible.

What we can summarize from all of this info is that:

TBI Gives you between 117-125hp at 5200rpm.

MPFI gives you 120-132hp at 5200rpm.

Not the 30hp difference you claim. The modern 2.4L I4 gives you around 150hp, but it is designed a lot better and more efficiently than the 2.5L.
Besides you lost the credibility you never had with me when you claimed our cooling systems were so over engineered they need a thermostat.
__________________
1995 YJ. 2 inch BDS Spring lift. 1 inch shackle lift. 1.25 inch JKS Body Lift 33x12.5x15's. Engo 10,000 pound winch.

[QUOTE=Magnum;14117863] I gave the Jeep the required offering of $$, sweat, and blood, and everything works fine now. -- Jim[/QUOTE]

[QUOTE=ldso;16498409]. It started with a $200 axle, and a few thousand dollars later I was done :)[/QUOTE]

[QUOTE=Luuca;16122017]diagnose the real issue before you start going all Obama on it - spending mad cash you'll need for other important things.

Ask me how I know...[/QUOTE]

[QUOTE=Overhead;17658665]this is also my second set of RC springs this year. I'd rather spend the money again and get something that will last.[/QUOTE]
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Unread 04-02-2013, 10:29 AM   #23
Xpress
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Join Date: Dec 2010
Location: The Great Big Box, California
Posts: 5,807
Fine, see ya. I don't have a single **** in the world to give. I have more important matters than proving someone wrong (once again) about 2.5L power output.

Believe your 30hp theory all you want, it's not true, not in the slightest. NOWHERE does Chrysler claim there to be a 30hp difference between the 2 engines.
__________________
[URL="http://www.jeepforum.com/forum/f12/another-5-2l-yj-thread-1503048/"]My 5.2L Build thread[/URL]

-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
[QUOTE=mudsweatNgearz;21162729]Leave em off and weld an I beam on. Bumperetts just scream homo.[/QUOTE]
"A well regulated Militia, being necessary to the security of a free State, the [B][I]RIGHT[/I][/B] of the people to keep and bear Arms, [B][I]SHALL NOT BE INFRINGED[/I][/B]."
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Unread 04-02-2013, 10:29 AM   #24
Xpress
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Quote:
Originally Posted by Siva283 View Post
Besides you lost the credibility you never had with me when you claimed our cooling systems were so over engineered they need a thermostat.
Let me asks you this:

Why, without a thermostat, do our engines run colder than they should?

And don't just use your heated opinion, use your brain.

Cooling systems are often intentionally over-engineered to provide MORE than enough ample cooling through a variety of climate changes. A thermostat is required to regulate the cooling temperature within a very small range to keep the engine at a specific operating temperature.
__________________
[URL="http://www.jeepforum.com/forum/f12/another-5-2l-yj-thread-1503048/"]My 5.2L Build thread[/URL]

-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
[QUOTE=mudsweatNgearz;21162729]Leave em off and weld an I beam on. Bumperetts just scream homo.[/QUOTE]
"A well regulated Militia, being necessary to the security of a free State, the [B][I]RIGHT[/I][/B] of the people to keep and bear Arms, [B][I]SHALL NOT BE INFRINGED[/I][/B]."
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Unread 04-02-2013, 10:30 AM   #25
Siva283
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Join Date: May 2011
Location: Falling Waters, WV
Posts: 3,698
Xpress
This message is hidden because Xpress is on your ignore list.
__________________
1995 YJ. 2 inch BDS Spring lift. 1 inch shackle lift. 1.25 inch JKS Body Lift 33x12.5x15's. Engo 10,000 pound winch.

[QUOTE=Magnum;14117863] I gave the Jeep the required offering of $$, sweat, and blood, and everything works fine now. -- Jim[/QUOTE]

[QUOTE=ldso;16498409]. It started with a $200 axle, and a few thousand dollars later I was done :)[/QUOTE]

[QUOTE=Luuca;16122017]diagnose the real issue before you start going all Obama on it - spending mad cash you'll need for other important things.

Ask me how I know...[/QUOTE]

[QUOTE=Overhead;17658665]this is also my second set of RC springs this year. I'd rather spend the money again and get something that will last.[/QUOTE]
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Unread 04-02-2013, 10:32 AM   #26
Xpress
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Join Date: Dec 2010
Location: The Great Big Box, California
Posts: 5,807
And now he is resorting to childish games. Guess I won the argument since he couldn't handle the facts being placed in front of him.

Idiots, idiots everywhere. And now I have 2 of them on my block list.

To the OP:

Don't believe anything that is said without facts to support it. The difference between the MPFI and TBI 2.5L engines is negligible. If the 2.5L MPFI engines had 160hp to put out, then people wouldn't be complaining about their inability to pull uphill, or having difficulty to get to highway speeds, even with 31" tires.
__________________
[URL="http://www.jeepforum.com/forum/f12/another-5-2l-yj-thread-1503048/"]My 5.2L Build thread[/URL]

-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
[QUOTE=mudsweatNgearz;21162729]Leave em off and weld an I beam on. Bumperetts just scream homo.[/QUOTE]
"A well regulated Militia, being necessary to the security of a free State, the [B][I]RIGHT[/I][/B] of the people to keep and bear Arms, [B][I]SHALL NOT BE INFRINGED[/I][/B]."
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Unread 04-02-2013, 10:58 AM   #27
Michaelgoesrawr
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Quote:
Originally Posted by Siva283
Xpress
This message is hidden because Xpress is on your ignore list.
Way to go Xpress. You made him mad and now I can't read his post either!
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Unread 04-02-2013, 11:34 AM   #28
flea1987
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How much mods would need to be made to drop in the 2.4? from what you said it's alot better than the 2.5, and I'll dow my own research before dropping in stuff
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Unread 04-02-2013, 11:37 AM   #29
flea1987
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HP difference is minimal between the 2 2.5's

http://www.allpar.com/mopar/amc-25.html

EDIT: Found this article
http://www.jeeparticles.com/reviews/...m#.UVsZf1eJ_IU
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Unread 04-02-2013, 11:45 AM   #30
flea1987
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and the 2.4 kills it in hp and torque

http://www.allpar.com/mopar/24.html
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