4.0l performance ideas - 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 Grand Cherokee & Commander Forums > WJ Grand Cherokee Forum > 4.0l performance ideas

Engo winches available at www.rockridge4wd.com! Free shippRockridge 4WD IS Taking Zone Offroad Suspension Lift Kits ZONE 4.25" combo lift for TJ available at Rockridge4w

Reply
Unread 12-19-2011, 03:19 PM   #1
rfritz7
Registered User
2004 WJ 
 
Join Date: Sep 2011
Location: York, PA
Posts: 201
4.0l performance ideas

I have a 04 jeep grand Cherokee with the 6cl 4.0l and I was wondering what good performance parts there are out there for it. I have a exhaust already that's a magnaflow and I'm looking at getting a K and N air filter. I also was looking at a throttle body spacer as well. I'm just wondering if there is anything else's out there to do to get better fuel economy. I was looking at the jet stage one and two computer chips but really don't know much about them, and also the bully dog performance meter that looks like a tuner for a jeep. please help me out I'm getting 14.5 miles per gallon now and would like to get better around town.

rfritz7 is offline   Reply With Quote
Unread 12-19-2011, 03:24 PM   #2
Jeepgcl9947
Registered User
 
Join Date: Oct 2011
Posts: 1,041
From what people told me the throttle body spacer is a waster of time and money. They say it don't do anything at all I've already asked. For cheap mods you can port and polish the throttle body. A k&n air intake. A magnaflow high flow catylatic converter.

99' Grand Cherokee Laredo 4.7 quadra dr
Jeepgcl9947 is offline   Reply With Quote
Unread 12-19-2011, 03:26 PM   #3
ExoticFish
Registered User
2004 WJ 
 
Join Date: Mar 2011
Location: Stuarts Draft, VA
Posts: 219
Get a V8 for performance... Get a hybrid for better MPG.
__________________
http://www.VAJeeps.com
ExoticFish is offline   Reply With Quote
Unread 12-19-2011, 03:27 PM   #4
Jeepgcl9947
Registered User
 
Join Date: Oct 2011
Posts: 1,041
Yea, forget the 4.7 though... I wanna see you drop a built 355 in that thing! Haha

99' Grand Cherokee Laredo 4.7 quadra dr
Jeepgcl9947 is offline   Reply With Quote
Unread 12-19-2011, 04:29 PM   #5
nickblack
Registered User
1999 WJ 
 
Join Date: Dec 2010
Location: bridgewater, nj
Posts: 740
All that after market stuff for the 4.0 is nonsense and a waste of money. The only worth while mod is to stroke it.
nickblack is offline   Reply With Quote
Unread 12-19-2011, 04:35 PM   #6
KayCeeJeep
Registered User
2004 WJ 
 
Join Date: Apr 2011
Location: Kansas City, Missouri
Posts: 1,103
The K & N will probably cost you mpg, not improve it. More air = More gas.

Plugs and a new fuel filter can help. I also use Marvel in my gas, the 4.0 loves it and I get much better mpg with it.
KayCeeJeep is offline   Reply With Quote
Unread 12-19-2011, 04:54 PM   #7
jfazio5188
Registered User
2002 WJ 
 
Join Date: Jul 2011
Location: warwick, rhode island
Posts: 70
K & N on the 4.0I6 will actually bring the same if not warmer air. The only place the cone can go is where the air box sits. Unlike most other vehicles where the cold air intake can wrap around to below the battery, or some other way to reach outside the engine bay. As far as stroking it, if you feel like it, go for it....or you can just buy a V8
jfazio5188 is offline   Reply With Quote
Unread 12-19-2011, 04:58 PM   #8
Ravie
Registered User
1999 WJ 
 
Join Date: Jul 2011
Location: Topeka, KS
Posts: 1,219
K&N filters are a waste of money unless you are driving a race-car. they suck in bigger particles than a good stock filter which wears your engine faster. They may bring power gains in some situations, but at the cost of wearing your bearings and rings out faster. There are better alternatives.
__________________
1999 WJ - Over 10k on the 4.0 rebuild. FB/BDS 2" lift (2.5") w/Bilstein 5125's. General Class Ham...KC0LUA
Burlbook48 sez "Nothing moves a project along faster than cubic dollars." Certified Thread Killer.
Ravie is offline   Reply With Quote
Unread 12-19-2011, 05:09 PM   #9
rfritz7
Registered User
2004 WJ 
 
Join Date: Sep 2011
Location: York, PA
Posts: 201
So what is good to do then buying a v8?
rfritz7 is offline   Reply With Quote
Unread 12-19-2011, 05:14 PM   #10
Ravie
Registered User
1999 WJ 
 
Join Date: Jul 2011
Location: Topeka, KS
Posts: 1,219
having the TB polished, porting and polishing the head, having the ECU flashed with a superchips flashpaq... there's nothing you can just "bolt on" that is going to make a huge difference. there just isn't.
__________________
1999 WJ - Over 10k on the 4.0 rebuild. FB/BDS 2" lift (2.5") w/Bilstein 5125's. General Class Ham...KC0LUA
Burlbook48 sez "Nothing moves a project along faster than cubic dollars." Certified Thread Killer.
Ravie is offline   Reply With Quote
Unread 12-19-2011, 05:23 PM   #11
rfritz7
Registered User
2004 WJ 
 
Join Date: Sep 2011
Location: York, PA
Posts: 201
How do I get all that done?
rfritz7 is offline   Reply With Quote
Unread 12-19-2011, 05:39 PM   #12
Ravie
Registered User
1999 WJ 
 
Join Date: Jul 2011
Location: Topeka, KS
Posts: 1,219
It depends. If it were me, I'd do it all myself. I don't know how mechanically inclined to are but you can't just willy nilly start grinding inside a port. doing it and KNOWING how to do it are two very different things..

Best thing to do is remove the head and bring it to an engine shop and ask them to do a deck skim, a mild port and a 3 angle valve job. The TB...I know there are a couple guys on this forum that can do it...cost is like 110 bucks I think? Not a huge difference, but a difference. If you're going to do them both, you can look for some decent gains. Don't expect miracles, but improvements.
__________________
1999 WJ - Over 10k on the 4.0 rebuild. FB/BDS 2" lift (2.5") w/Bilstein 5125's. General Class Ham...KC0LUA
Burlbook48 sez "Nothing moves a project along faster than cubic dollars." Certified Thread Killer.
Ravie is offline   Reply With Quote
Unread 12-19-2011, 06:06 PM   #13
gphunkplp
Registered User
1999 WJ 
 
Join Date: Jul 2011
Location: , NY
Posts: 344
save your cash and gear it 4. 10 or 4.56s a good tune up port and polish and some rotella oil changes the 4.0 loves that oil. the 4.0 and 4.7 both get about the same mpgs believe it or not. jeeps werent known for there mileage.

Sent from my optimus
gphunkplp is offline   Reply With Quote
Unread 12-19-2011, 06:16 PM   #14
Jeepgcl9947
Registered User
 
Join Date: Oct 2011
Posts: 1,041
[QUOTE=save your cash and gear it 4. 10 or 4.56s a good tune up port and polish and some rotella oil changes the 4.0 loves that oil. the 4.0 and 4.7 both get about the same mpgs believe it or not. jeeps werent known for there mileage.

Sent from my optimus


But I would stick to around 4.10 gears 4.56s could be harsh on the highways with stock tires.

99' Grand Cherokee Laredo 4.7 quadra dr
Jeepgcl9947 is offline   Reply With Quote
Unread 12-19-2011, 06:16 PM   #15
MeanGreenZJ
Web Wheeler
 
Join Date: Apr 2011
Location: Mean Street in a desperate part of town
Posts: 1,710
More performance and better fuel economy all at the same time?
MeanGreenZJ is offline   Reply With Quote




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.