Need experienced feedback on carb/manifold/header selections - JeepForum.com
 16Likes
Reply
 
LinkBack Thread Tools
post #1 of 32 Old 05-02-2020, 03:22 PM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
Cj Need experienced feedback on carb/manifold/header selections

Restoring my 1980 CJ7 and want to upgrade the left side of the engine a bit. Original 258 overhauled by a professional shop and cam upgraded to a Comp Cam X4250H. After surveying as many threads as I think I can absorb, here's the setup I'm considering and would appreciate constructive feedback on the combination including pros, cons, better solutions. Don't want to use original iron manifolds and curb appeal also plays into the performance goal.

CJ will be a football tailgate toy to pass on to kids/grandkids and be driven mostly on the street. Thanks in advance for the help, and here's a picture of current condition just to whet your appetite. See my signature for the rebuild thread. Be safe out there and thanks again.

Holley 4160, 390 CFM, 4bbl, electric choke, vacuum secondary (Summit Racing)
Offenhauser 5999DP, dual plane, 4bbl (Summit Racing)
Hedman Headers 99606, High Temp Coating, dual outlets

Attached Thumbnails
IMG_2248.jpg  

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
Sponsored Links
Advertisement
 
post #2 of 32 Old 05-03-2020, 09:09 PM
oldschool74cj5
Registered User
 
Join Date: Jan 2017
Posts: 503
hello

i would just keep it simple. remember the 258 is a tractor motor. its a low rpm stump puller.
1)put a factory 81 up aluminum manifold. the electric heater helps when engine is cold, its also water heated.
2) carb again keep simple i love the weber 38 but another good is a ford 2100 or 2150 carb with a 1.08 venturi. both are easy to tune. i have heard that the ford one stays tuned longer. also it is a better carb for 4 wheeling.
3) i like a single outlet header. exhaust is easier to get made.

oldschool
BagusJeep, 74G8R2 and STJP like this.
oldschool74cj5 is offline  
post #3 of 32 Old 05-04-2020, 10:09 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
Quote:
Originally Posted by oldschool74cj5 View Post
hello

i would just keep it simple. remember the 258 is a tractor motor. its a low rpm stump puller.
1)put a factory 81 up aluminum manifold. the electric heater helps when engine is cold, its also water heated.
2) carb again keep simple i love the weber 38 but another good is a ford 2100 or 2150 carb with a 1.08 venturi. both are easy to tune. i have heard that the ford one stays tuned longer. also it is a better carb for 4 wheeling.
3) i like a single outlet header. exhaust is easier to get made.

oldschool
Thanks OldSchool for that dose of reality. Keeping it simple has been my goal from the start so I will rethink. One thing that was driving my choices was the limited choices of manifolds (Factory, Clifford or Offy). I hadn't considered looking at the '81 up aluminum manifold as you mentioned but I will now. I had originally planned on the Clifford Performance kit (that uses the Weber carb) but I've read too many negative comments on their current quality and fitment. thanks again...

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
 
post #4 of 32 Old 05-04-2020, 10:49 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
I would still welcome other input on these selections or your alternate ideas. Thanks

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #5 of 32 Old 05-04-2020, 12:46 PM
uptillnow
Web Wheeler
 
uptillnow's Avatar
 
Join Date: Mar 2009
Location: Fountain Valley
Posts: 1,263
Quote:
Originally Posted by 74G8R2 View Post

CJ will be a football tailgate toy to pass on to kids/grandkids and be driven mostly on the street.
My $0.02 cents worth.
For your usage as stated above.....

1. I too really like the later model stock aluminium manifolds. They have normal to smaller plenums, and normal to smaller diameter intake runners and have HEAT to them. This manifold is most desirable from 800-5200 power range.

2. Camshafts are a tough choice. I used the Comp Cam 260 and was a little out of my "realistic driving range", although I liked it. Shawn Watson seems to have a lot of experience with many cam grinders and engine/manifold combinations. I'm sure he will chime in here at some time. Mr. Camshaft himself says, and I agree... That keeping a lobe separation angle LSA of 107 with +4 degrees advance will keep that extreme low RPM torque and very good mid range power that these tractor engines are known for. 252 advertised duration, with 206 @ 0.050", with around 0.454" valve lift is around what you are looking for.

3. Headers are an improvement over the stock cast iron style exhaust systems.

4. A performance HEI, like the D.U.I. brand is a huge improvement over the stock Duraspark ignition. DUI utilizes their GM 4 pin style module and their High Performance coil that will create much more spark energy, and a longer duration of spark at the plug. The stock Motocraft distributor using the 18r advance slot gives 18 degrees total distributor advance, "IF" you have the 18r advance head, much less advance if you have a smaller slot. The DUI gives you 22 degrees total distributor advance.

5. I use, work on, and Highly recommend the Weber 38-DGES (NOT the 32/36) with this set-up/combination. The Weber is much more tunable than any other carburetor. (The Motorcraft 2100/2150 are good, and reliable, but not as tunable) There are many guys on this forum who are very experienced tuners, from very large camshafts and engine modifications, to completely stock (except the Weber) trying to pass tail pipe emissions, not visual requirements. Because of the Weber's tunability, sometimes there is a "tuning learning curve" when not stock or slightly modified. But once they are set-up, they don't go out of tune any more than any other carburetor does from dirt, vacuum leaks, bolts falling off, etc.

I am looking forward to following your choices and your build, Good luck. There are a lot of smart people on this forum.

UTN
74G8R2 likes this.
uptillnow is offline  
post #6 of 32 Old 05-05-2020, 07:42 AM
Shawn Watson
Registered User
 
Shawn Watson's Avatar
1983 CJ7 
 
Join Date: May 2009
Location: Texas Hill Country
Posts: 7,625
I'm in agreement with Mr. UTN on this one.

Years ago, I wanted to weld up the factory aluminum intake just under the carb flange and reshape those little shotgun barrels to better match the throttle bore size of a Weber 38 but I never got the chance. There really aren't any good intake options unless you're trying to turn a tractor into something it isn't.


Shawn

Live in a way that those who know you but don't know God will come to know God because they know you.
Shawn Watson is offline  
post #7 of 32 Old 05-05-2020, 07:40 PM
HighCountry
Registered User
1986 CJ7 
 
Join Date: Aug 2001
Location: North East Texas
Posts: 1,038
Just be aware, unless some thing has changed you can not find a REAL Air Filter Housing to fit the 'retard' Weber carb design. And anyone that thinks those oiled cloth rags (K&N and Etc.) are filters need to do some research.




Bruce
HighCountry is offline  
post #8 of 32 Old 05-05-2020, 11:28 PM
ddawg16
Registered User
 
ddawg16's Avatar
1984 CJ7 
 
Join Date: Oct 2018
Location: South Bay
Posts: 725
Garage
Quote:
Originally Posted by uptillnow View Post
My $0.02 cents worth.
For your usage as stated above.....

1. I too really like the later model stock aluminium manifolds. They have normal to smaller plenums, and normal to smaller diameter intake runners and have HEAT to them. This manifold is most desirable from 800-5200 power range.

2. Camshafts are a tough choice. I used the Comp Cam 260 and was a little out of my "realistic driving range", although I liked it. Shawn Watson seems to have a lot of experience with many cam grinders and engine/manifold combinations. I'm sure he will chime in here at some time. Mr. Camshaft himself says, and I agree... That keeping a lobe separation angle LSA of 107 with +4 degrees advance will keep that extreme low RPM torque and very good mid range power that these tractor engines are known for. 252 advertised duration, with 206 @ 0.050", with around 0.454" valve lift is around what you are looking for.

3. Headers are an improvement over the stock cast iron style exhaust systems.

4. A performance HEI, like the D.U.I. brand is a huge improvement over the stock Duraspark ignition. DUI utilizes their GM 4 pin style module and their High Performance coil that will create much more spark energy, and a longer duration of spark at the plug. The stock Motocraft distributor using the 18r advance slot gives 18 degrees total distributor advance, "IF" you have the 18r advance head, much less advance if you have a smaller slot. The DUI gives you 22 degrees total distributor advance.

5. I use, work on, and Highly recommend the Weber 38-DGES (NOT the 32/36) with this set-up/combination. The Weber is much more tunable than any other carburetor. (The Motorcraft 2100/2150 are good, and reliable, but not as tunable) There are many guys on this forum who are very experienced tuners, from very large camshafts and engine modifications, to completely stock (except the Weber) trying to pass tail pipe emissions, not visual requirements. Because of the Weber's tunability, sometimes there is a "tuning learning curve" when not stock or slightly modified. But once they are set-up, they don't go out of tune any more than any other carburetor does from dirt, vacuum leaks, bolts falling off, etc.

I am looking forward to following your choices and your build, Good luck. There are a lot of smart people on this forum.

UTN
I tried the 'upgrade' path twice on my jeep.....cam....porting the head...etc.

The biggest improvement was an HEI dist.....and fixing all the vacuum leaks.

Unless you go FI, you are just not going to get a whole lot more out of that motor. But I do agree with uptillnow on the carb. I had the old Carter BBD....the hours I spent on it.

I now have a 5.7L TBI.....I'll never go back to carbs.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
ddawg16 is online now  
post #9 of 32 Old 05-06-2020, 11:20 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
UTN, great feedback, just what I was looking for.
1. OK with the aluminum intake but where can i find one? have't had any luck with normal suppliers like Quadratec, Summit, etc.
2. Camshaft is done so no changes there.
3. Any recommendations on headers? Or any known issues on the Hedman single outlet suggested by Old School?
4. Have been planning on the D.U.I. HEI. Should i go all in on the rebuild (which might make trouble shooting tougher if there are any issues) or rebuild with factory ignition/dizzy/etc and then modify after I get it running again?
5. Agree, the 38DGES was my first choice on 2bbl carbs. If I decide against the factory alum intake, would it also work on the Offy 4bbl intake?
Much thanks...

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #10 of 32 Old 05-06-2020, 11:22 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
Quote:
Originally Posted by Shawn Watson View Post
I'm in agreement with Mr. UTN on this one.

Years ago, I wanted to weld up the factory aluminum intake just under the carb flange and reshape those little shotgun barrels to better match the throttle bore size of a Weber 38 but I never got the chance. There really aren't any good intake options unless you're trying to turn a tractor into something it isn't.


Shawn
Shawn, Appreciate the input and your world view. Blessings,

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #11 of 32 Old 05-06-2020, 11:23 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
Shawn BTW, replying to you from Lake Buchanan this week.
Shawn Watson likes this.

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #12 of 32 Old 05-06-2020, 11:25 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
High Country ... duly noted ... thanks

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #13 of 32 Old 05-06-2020, 11:26 AM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
ddawg, thanks for the feedback and confirmation on HEI

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
post #14 of 32 Old 05-06-2020, 04:07 PM
stripperguy
Registered User
2005 LJ Wrangler 
 
Join Date: Mar 2010
Location: Schenectady
Posts: 760
FWIW, I have a similar build as your wish list.

Comp Cams 252H
Clifford intake
Weber 38DGAS
Hedman 6 into 1 headers
All 2.25" exhaust with Flomaster 40
HEI distributor
Electric fan

It's plenty powerful and sounds fantastic, often mistaken for a V8.
And yes, the guys here helped me tune the Weber, it was a little tricky, I think because of the Clifford intake. Couldn't have done it without their help.
uptillnow likes this.

1977 CJ5 is a CJ build ever really done?
2002 TJ gone
2005 TJ also gone
2005 LJ insurance wreck
stripperguy is offline  
post #15 of 32 Old 05-06-2020, 04:27 PM Thread Starter
74G8R2
Registered User
1980 CJ7 
 
Join Date: Jul 2013
Location: Spring
Posts: 39
Quote:
Originally Posted by stripperguy View Post
FWIW, I have a similar build as your wish list.

Comp Cams 252H
Clifford intake
Weber 38DGAS
Hedman 6 into 1 headers
All 2.25" exhaust with Flomaster 40
HEI distributor
Electric fan

It's plenty powerful and sounds fantastic, often mistaken for a V8.
And yes, the guys here helped me tune the Weber, it was a little tricky, I think because of the Clifford intake. Couldn't have done it without their help.
Great info stripperguy, did you buy one of the Clifford Weber/Intake/Header kits, i.e.
6=8J242?Or did you purchase them separately? Also, what's your impression of fit & finish on the Clifford components? I've read a lot their product has slipped in recent years. Thanks

Camper
My 1980 CJ7 Build Thread: http://www.jeep-cj.com/forums/f98/1980-cj7-love-ya-blue-19508/
74G8R2 is offline  
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.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome