New Carb Shopping

Tug-n-pull

New member
79 CJ7 4.2 with orginal carb. I have studied them a bit still have no idea as to the best choice. Bounty hunter mentioned someone he whells with running a Holly Truck Advenger the thing is 670 cfm or more is that not a little big on the I6. The Webber seems to be very well liked and disliked and problematic at best. The Stock carb is really no great picnic for sure. Injection is just not an option as the cost is just out the roof. Give em a little feed back if you have a choice and some info please. Can't take the stock deal much more it is worn out and sad. tug
 

soft doors

If you want to keep it simple there is no better way than the Weber. If you know or can learn anything about carbs, they're just as straight forward as possible. If your 4.2 is stock, or close to it, it will only make it better. Your in luck since your '79 doesn't have the stepper motor on the back of the carb or the associated EEC(computer) unit. If it did, or does, you'd have to bypass the EEC and all the sensors and trinkets that go along with it. I realize that some people have had problems with tuning them. Most carb tuning problems can be related back to vacum leaks either from a leaky(improperly installed) gasket, missing or misplaced vacum lines, or occasionally impoper jetting. The Weber's are shipped with a one size fits all jet size that should work on most any application. They get the bulk of there fuel mixture from the low speed mixture adjustment. Most Jeeping is at low speed.

Which ever you pick, I would suggest a two barrel or small four barrel. There is really no need for the large (500+ CFM) carbs on a small normally aspirated engine like the 258.

Holley makes a cool offroad kit for their carbs that eliminates the stalling and flooding problems associated with steep climbs/descents/sidehills. I think it is a fuel bowl that changes the position of the float and jets. I thought about this but eventually went with Weber since I had more history there.

Check out this web site http://www.bob2000.com/carb.htm It's got some good basic info on carbs, but the message is kinda universal for all carbs. There's some other cool info too, but it get's kinda deep.

Good luck.
 
Thanks for the info I will read and digest the info along with all the other stuff I have gathered. Welcome to jeepz and sounds like you will have a lot to offer here. Good to have you aboard. tug
 
I've heard mixed reviews on the holley, particularly for offroad reliability and steep inclines.
As far as the Weber goes, I've rarely heard complaints except from people trying to figure out how to hook up all the vacuum hoses. :roll:
Also, correct me if i'm wrong, but i think the holley requires a new intake manifold to work properly, where the weber is pretty much "bolt on"

Fuel injection is still horribly and unreasonably expensive for our engines, not to mention that apparently the wiring is a nightmare.
 

From what I understand both the two barrel holley and the two barrel webber require adapter plates to bolt to the intake. I am planning on installing a Holley 350cfm. That is the carb that my uncle used on his 4.2 and he loved it. The Holley is very tuneable (if that is a word). From what he told me, it is a simple carb to change jets, power valves, accelerator pump cams on.
 
Baton Rouge, LA

Tug -

thought you might want to see my holley for info-

http://home.kc.rr.com/jeepcj7/holley1.jpg

http://home.kc.rr.com/jeepcj7/holley2.jpg

http://home.kc.rr.com/jeepcj7/holley3.jpg

it is a 350cfm 2bbl. mounted to a Clifford intake (i also have headman headers but they are going to be replaced do to a crack) only one thing, i have a manual choke but you can get an electric one aftermarket if you wanted. there are tons of these carbs on ebay also...

no emissions on it, but it runs strong with no hesitation. (I also have a DUI distributor which helped a TON!)

it's an 81 so there was some work to do to remove electrical/emissions but that was done by previous owner...

Brad.
 
I'm not sure about offroad quality but for on road nothing is better than a Holley. They are easily tuned and can give much better power if done well(if your interested in that). Not sure how great a Weber is but then again most stuff i see is racing. Performance wise go with a Holley. I definitely do some reading of reviews tho.
Mike
 

The pre BBD Carter isn´t a bad carb. I´ve used the old one barrel Carter on most every engine Chrysler ever produced. The one barrel, while not the highest in HP, pulls real good with big tires at low RPM´s.
I´d research a two barrel with progressive linkage, makes sense for most 4X applications.
Ford pulled some heavy horses, out of some small I-6`s with there two barrels.
 
I agree with MudderChuck, the Carters from the early '80's (pre '84 anyway) were simple and reliable. The only downfall in my mind is the metering rods. Those things are tedious and tempermental if your not real familiar with them.

I think all these carbs would be a good choice. Unless your talking about some serious angles the offroadability is something that can be tweaked a little when you tune the carb.

You can usually find any of these carbs used on EBAY. I got my Weber 32/36 as a used Jeep kit. I got lucky and have had great luck with it. The new kits come with the adapter plates. But if your adventureous you could pick up just the carb and fab you're own adapter from aluminum plate. :idea:
 
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