4.0 Head Swap on 4.2L 258 - 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 CJ Forum > 4.0 Head Swap on 4.2L 258

TeraFlex Now at Rockridge 4WD! BEST DEALS around!Alloy usa heavy duty ball joint kitsENGO QUADLUX 6" to 54" LED AMBER AND WHITE MULTI

Reply
Unread 01-03-2011, 11:57 PM   #1
WillyC24
Member
1980 CJ7 
 
Join Date: Aug 2010
Location: Dallas, Texas
Posts: 143
4.0 Head Swap on 4.2L 258

Does anyone have experience/wisdom to share on this particular product?

http://www.4wd.com/productdetails.aspx?partID=40362#

It's the Alabama Cylinder 4.0 head which can be put on the 4.2L. I've read some articles with conflicting advice on whether to use a junkyard head, Clearwater, or Hesco; in addition to specific model years where there are concerns about the heads cracking.

Also, is this a good price? Many thanks.

WillyC24 is offline   Reply With Quote Quick reply to this message
Unread 01-04-2011, 10:13 AM   #2
WillyC24
Member
1980 CJ7 
 
Join Date: Aug 2010
Location: Dallas, Texas
Posts: 143
As a follow-up, from all the reading I've done about the 4.0L head swap, the only actual product that I can find on the internet is the Alabama Cylinder link above. (Well, there's the Hesco aluminum head, too)
WillyC24 is offline   Reply With Quote Quick reply to this message
Unread 01-04-2011, 11:25 AM   #3
VaCJ79
Registered User
1979 CJ7 
 
Join Date: Oct 2006
Location: , ND/VA
Posts: 434
I got mine from clearwater, 7120 out of a 94, they sell through ebay.
__________________
1979 CJ7 258 / 4.0 head / J20 power Steering / T150 Dana 20 / EMU YJ 2" lift / Custom front bumper

Looking for : Please PM, Carter 2 barrel Carb before you through it out
VaCJ79 is offline   Reply With Quote Quick reply to this message
Unread 01-04-2011, 11:28 AM   #4
foggybottombob
Registered User
1984 CJ7 
 
Join Date: May 2008
Location: Monument Colorado
Posts: 5,830
I got one from clearwater also but I will say that I could not tell any difference in seat of the pants power difference. I got a very noticeable power increase from putting in the HEI distributor.
foggybottombob is offline   Reply With Quote Quick reply to this message
Unread 01-04-2011, 05:35 PM   #5
swatson454
Mall-crawlin' Hot Rodder
 
swatson454's Avatar
1983 CJ7 
 
Join Date: May 2009
Location: Dripping Springs, TX (soon)
Posts: 4,913
So what header options does one have when using a 4.0 engine in a CJ? Any long-tube, single-out options?


Shawn

*Edit* And what are the stock valve sizes of said 4.0 7120 head?
__________________
Live in a way that those who know you but don't know God will come to know God because they know you.
swatson454 is offline   Reply With Quote Quick reply to this message
Unread 01-17-2011, 10:22 AM   #6
johnson30
Registered User
1978 CJ5 
 
Join Date: Aug 2009
Location: Richmond, Va
Posts: 74
Hesco

Hesco sells a 4.0 with the water jackets sealed, gives you a 4.0 valve cover, and the gasket for $1100. Pricey, yes, but I didnt want to seal water jacket ports. And I got a pretty sweet looking aluminum valve cover with it (included).

So, depends on if you want the bolt-on product delivered to your door (like me), or you want to do the work yourself.
johnson30 is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 11:40 AM   #7
WillyC24
Member
1980 CJ7 
 
Join Date: Aug 2010
Location: Dallas, Texas
Posts: 143
Can I ask where you found that price? The 4.0 head I've seen on Hesco's website is $1,999. Yikes....

http://www.hesco.us/shop.asp?action=...115&catId=7735
WillyC24 is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 11:48 AM   #8
Ben_88Jeep
Vendor
2010 JK Wrangler 
 
Join Date: May 2008
Location: Delta, B.C.
Posts: 517
I did the 4.0 head swap from a junkyard in my 88 YJ and noticed a really good power gain in the low end. The only downside to going junk yard is that you will have to machine the head and fill in the ports. When you factor in the cost of the head and the machine shop work, you are almost better off to get one that's already done.
Ben_88Jeep is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 01:12 PM   #9
mcmud
Web Wheeler
1983 CJ8 
 
Join Date: May 2008
Location: N.E. Alabama
Posts: 2,650
Quote:
Originally Posted by swatson454 View Post
..... what are the stock valve sizes of said 4.0 7120 head?
While I can't exactly answer the question to that particular head, the "Mopar Performance Parts Jeep Engines" build manual list the 4.0 intake valve head diameter as being 1.782-1.792" and the exhaust as 1.401-1.411"

In speaking with Ron McGinnis @ Alabama Cylinder Head, I'll offer this. He tells me that they cast (iron), mill and installs all new parts while using the #0331 head pattern. That intake valve head diameter is 1.90" and the exhaust head is 1.49".

Alabama Cylinder Head is affiliated (in house) with "Patriot Performance" If the head is walked across the hall then that modification process includes a five angle hardened seat insert installed, its bowl blended and the runners are "cleaned", Patriot Gold springs are installed.

Ron can be reached @2564426773

I want to point out that the modification to the water jacket holes is not performed.
mcmud is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 02:22 PM   #10
swatson454
Mall-crawlin' Hot Rodder
 
swatson454's Avatar
1983 CJ7 
 
Join Date: May 2009
Location: Dripping Springs, TX (soon)
Posts: 4,913
Great info, thanks!


Shawn
__________________
Live in a way that those who know you but don't know God will come to know God because they know you.
swatson454 is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 02:32 PM   #11
WillyC24
Member
1980 CJ7 
 
Join Date: Aug 2010
Location: Dallas, Texas
Posts: 143
Thanks, McMud! Did Ron give you a price on that mod to the head? Their "stock" 0331 head is $495.

http://www.acheinc.com/productdetail.php?id=109
WillyC24 is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 02:50 PM   #12
mcmud
Web Wheeler
1983 CJ8 
 
Join Date: May 2008
Location: N.E. Alabama
Posts: 2,650
No, price was not discussed.
mcmud is offline   Reply With Quote Quick reply to this message
Unread 01-21-2011, 08:32 PM   #13
johnson30
Registered User
1978 CJ5 
 
Join Date: Aug 2009
Location: Richmond, Va
Posts: 74
Hesco 4.0L head conversion Kit Price

Hesco's site is a little confusing....you have to hunt for it. Even having bought the thing, it just now took me about five minutes to find it.

What you saw immediately was the price for the aluminum head ($1,995.00).

Way to expensive for me.

Here's the information from the website on the standard head. Hesco modifies the head to accommodate the 4.2L intake, but they say they will weld the mounting studs on wherever you want them and that it can be reversed later to take the 4.0 intake. I was really happy with this- showed up at my door and I put it on. Done.

Cylinder Head Conversion Kit #HES4240CHC
Price: $1,150.00
Description: Converts the 4.2L to the 4.0L cylinder head using the superior 1991-up high port head casting. Designed to let your fuel starved 4.2L perform to its fullest potential. Provides a snappy throttle response with increased torque and horsepower. Complete bolt-on kit includes modified cylinder head with head gasket and valve cover. Will require a 4.0L exhaust manifold or header.
Part Number: HES4240CHC
Manufacturer: Hesco
Application 1: 4.2L Six Cylinder Jeep engines, to be converted to 4.0 head design.
johnson30 is offline   Reply With Quote Quick reply to this message
Unread 01-26-2011, 10:26 AM   #14
WillyC24
Member
1980 CJ7 
 
Join Date: Aug 2010
Location: Dallas, Texas
Posts: 143
Good discussion everyone, thanks. Three follow-up questions:

1) I've got a new 4.0L intake and exhaust manifold, so I don't need those mods. Is this head that Hesco sells already modified to accept the 4.2L intake?

2) Do you believe the 2x price difference with the Hesco is worth it over the Alabama Cylinder Head?

3) A bit of a random one, but what fuel pump would be most strongly recommended?
WillyC24 is offline   Reply With Quote Quick reply to this message
Unread 01-26-2011, 10:24 PM   #15
johnson30
Registered User
1978 CJ5 
 
Join Date: Aug 2009
Location: Richmond, Va
Posts: 74
Some opinion, some fact....

1) Hesco does whatever you want them to do, so to me that is a great advantage. They set it up for either the 4.0 intake or the 4.2, and they told me that if I changed my mind, I could have the mounting studs moved in the future, so I liked the sound of that.

2) I'd say that having the head delivered with the water jackets filled, a new valve cover, valve cover gasket (the metal and rubber type- not cork), and really expensive head gasket (it's the metal kind, with several layers...the factory gasket is more like one layer with some kind of felt on it....the Hesco gasket is clearly a high-pro version). So if you add up all the trouble of getting the modifications done, and finding and buying the upgade parts, I'd say yeah, it is worth it. I got the thing in the mail and installed it. Bing bang boom. Add it all up and compare- you are still paying more, but for me it was paying to remove a headache. You do need to buy new head bolts for a 4.0, something else I mistakenly forgot in my excitement.

3) I used a weber carb, so not sure from you saying that you have a 4.0 intake if your intent is to do a full MPI swap, but I'll give you my experience whether it helps or not (might help someone): I maintained the factory pulse fuel pump, and I wish I hadn't. I had to use a fuel regulator, and the fuel lines go everywhere because of mounting locations, and I still have the hard fuel line that runs over the valve cover (which I hate), and the pressure gauge pulses, so my perfectionist self wishes that I had coughed up a couple bucks for an electric fuel pump for the weber, which I know is available.

Maybe someone else can answer this one for the MPI if that is your intent.
johnson30 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.