Supercharged 99 4.7 WJ?? - 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 Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Supercharged 99 4.7 WJ??

Rampage Bowless Soft Top Oconee offroadAlloy USA Still AvailableAdvance Adapters SYE Kits

Reply
Unread 10-03-2009, 06:25 PM   #16
WiCkeDuDe
Web Wheeler
 
WiCkeDuDe's Avatar
2002 WJ 
 
Join Date: Dec 2007
Location: Utah
Posts: 3,121
Quote:
Originally Posted by the88thpianoman View Post
It needs premium because of the upgrade internals being designed to run on it. But with the stock 4.7 computer, you don't have the feature in the HO computer that detects the usage of lower octane gas to retard the timing. It uses multiple knock sensors that don't exist on the regular 4.7 and thus there is no input on the computer. So you just have to default to premium gas.
Saw this info on wjjeeps just now.

So if the HO could be run on pump on non premium gas I still dont see why it matters. If it is to prevent detonation again I dont see how it could matter as the compression ratio is lower. The PCM isnt trying to advance the timing either if no changes are made to it.

Anyone done this swap?

__________________
I Have WJ Stuff for Sale

99 - 04 Grand Cherokee Mopar Trackbar
NP 242HD Transfer Case


Last edited by WiCkeDuDe; 10-03-2009 at 06:52 PM..
WiCkeDuDe is offline   Reply With Quote Quick reply to this message
Unread 10-03-2009, 07:07 PM   #17
488TJ
Registered User
1988 YJ Wrangler 
 
Join Date: Mar 2009
Location: Nashua NH
Posts: 157
^ sorry thought it was just speedfreaks.net and it didnt work ill take a look

do u have a build thread rm2001wj
488TJ is offline   Reply With Quote Quick reply to this message
Unread 10-03-2009, 07:42 PM   #18
the88thpianoman
Registered User
2003 WJ 
 
Join Date: Apr 2008
Location: Tampa, FL
Posts: 5,252
Quote:
Originally Posted by WiCkeDuDe View Post
Saw this info on wjjeeps just now.

So if the HO could be run on pump on non premium gas I still dont see why it matters. If it is to prevent detonation again I dont see how it could matter as the compression ratio is lower. The PCM isnt trying to advance the timing either if no changes are made to it.

Anyone done this swap?
I could be wrong, but I think it relates to the cam and the timing. Normally it is slightly advanced and defaults to requiring premium, but the knock sensors on the HO allow you to run regular.
__________________
2003 WJ in Jeep Green Metallic, 4.0/242/4.10's. 4" Teraflex springs w/ RE monotube shocks and IRO short arms, cheap intake w/ amsoil filter, 2.5" hi flow cat and back exhaust, lots of lights and other misc crap.

Check out my build thread here: Life lessons and budget build
the88thpianoman is offline   Reply With Quote Quick reply to this message
Unread 10-04-2009, 09:07 AM   #19
vansskaterfreek
Registered User
1998 ZJ 
 
Join Date: Jul 2008
Location: ocean city, nj
Posts: 486
chrysler had no issues with their 4.7's or 2.7's its the owners fault 99% of the time.... either not changing the oil and building up sludge ( 2.7, 3.7, 4,7, and even the 5.7) or overheating it by letting their water pump leak forever.. they are good motors, its just the owners fault for not taking care of it
__________________
1998 ZJ 5.9L 122k miles - DD, 242 swap, 3.5" RE, 32" BFG M/T, safari rack, roof-mounted lights, custom steel front bumper with hitch reciever, 10k winch :)
2004 WJ 4.7L 107k miles - her daily driver, 2" daystar BB with scorpion shocks.. not too bad! stuffed 265/65/17 General Grabber AT2'S
vansskaterfreek is offline   Reply With Quote Quick reply to this message
Unread 10-04-2009, 09:23 AM   #20
JrMechanic
Registered User
 
JrMechanic's Avatar
1993 ZJ 
 
Join Date: Oct 2008
Location: Lima, Ohio
Posts: 3,368
Quote:
Originally Posted by vansskaterfreek View Post
chrysler had no issues with their 4.7's or 2.7's its the owners fault 99% of the time.... either not changing the oil and building up sludge ( 2.7, 3.7, 4,7, and even the 5.7) or overheating it by letting their water pump leak forever.. they are good motors, its just the owners fault for not taking care of it

I'll agree with you on the V8's, but fact of the matter is the 3.7 WAS a POS.

Back on topic, you're probably best checking out a Dodge Forum for info on supercharging a 4.7. I know of several cammed and blown 4.7L Rams and Dakotas.
__________________
Want to swap an NP242 or NP231 into your ZJ? Here's how:
http://www.jeepforum.com/forum/f13/n...pdated-685644/
JrMechanic is offline   Reply With Quote Quick reply to this message
Unread 10-05-2009, 01:51 AM   #21
Kramer H
Built and Supercharged 47
 
Kramer H's Avatar
2001 WJ 
 
Join Date: Feb 2008
Location: Everett, Washington.
Posts: 1,952
I, too, am thinking about doing the H/O swap on my 01, but was told different storys by different people. i have a superchips tuner, and was thinking about finding a junkyard donor and pulling the heads off the H/O motor concidering the cams are on national backorder.
__________________
Built Beater 01 WJ MY BUILD THREAD
Swapped, SUPERCHARGED Locked, Lifted and Long Armed.
02 Cummins. It has a smoking problem, And it wont quit.
K8 GSXR 1000- Racefit,Comp Werks,Puig,Woodcraft,B2 Industries,55W HID'S, R&G Engineering, Two brothers, ASV, DDM, "The pantie dropper"
Kramer H is offline   Reply With Quote Quick reply to this message
Unread 10-05-2009, 02:58 AM   #22
kentman
Registered User
2006 XK Commander 
 
Join Date: Jan 2004
Location: Wilmington, NC
Posts: 1,429
The 4.7L is a good motor. It is no worse than any other.

I would not supercharge. The 4.7L is plenty good for the platform. This is coming from someone with a supercharged MX-5 sitting in the garage. Have you hit any situations where the 4.7L is not enough? You are just begging for reliability issues if you modify the motor. Enjoy your ride for what it is, and save that money for your next purchase.

If you must spend money, you would be better served doing wheels and lift. Save the forced induction for RWD track cars with manual transmissions.
__________________
'06 XK Limited, 5.7L, QD II, Black, 125K
'02 WJ Overland, 4.7L HO, QD, Inferno Red, 102K
kentman is offline   Reply With Quote Quick reply to this message
Unread 10-05-2009, 06:20 AM   #23
CanadianZed-J
Registered User
1999 WJ 
 
Join Date: Sep 2005
Location: Sudbury, ON.
Posts: 688
Quote:
Originally Posted by JrMechanic View Post
...probably best checking out a Dodge Forum for info on supercharging a 4.7. I know of several cammed and blown 4.7L Rams and Dakotas.

That's what I was going to suggest. Get on the Ram and Dakota forums. We all use the 4.7 but I'd imagine here at JF we're more interested in offroad ability than street performance (which is why we still drool over Jeeps with $50,000 of upgrades running a bone stock engine).



Yes, I'm also a believer in the 4.7, however, it's no different from any other engine in that when you make it push more power you're going to lose some reliability.


CZJ.
__________________
So I installed the flux capacitor but the Jeep just won't do 88 mph.

-'99 WJ Limited, 4.7, Patriot Blue, 2" BB, 31" Mall-Terrains, Pavement Princess
-'97 TJ, Stone White, 4" Superlift, 33" SSRs, lunchboxed rear, 12K Titan winch, and 2.5 litres of exhillirating performance.
CanadianZed-J 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


Suggested Threads





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.