[Jeepkid1995]

Hey guys, I have a Carter BDD (which is stock, I believe) on a '79 CJ7 with a 258. After a rebuild, I have a few extra hoses lying around and I can't find a home for them. Anyone have a picture of theirs? I am also looking to replace the carb in the name of fuel efficiency. Is this carb decent for mileage? If not, which one will get me the best fuel economy? I know It's a CJ, and I am not expecting 30mpg or something, but simply the best possible carb for fuel efficiency. Also, completely unrelated, what does a heat stove do and is it necessary? To my understanding, it helps the engine warm up. Is that needed in 20+ degree weather? (Celsius). Again, any help, ideas and opinions are greatly appreciated. Thanks!

[John Strenk]

Well best one is a toss up. I guess it would be one that you can keep in tune. anything that causes a miss fire means you lost 1/6 of your fuel economy.

I was getting 20 mpg with my 1 bbl.

In theory, the Weber with the small primary should give you the best but there are a lot of Webers out there getting worse mileage than I am. But who want's to go back to a 1 bbl.

IF it's really important then look at FI either a throttle body or MPFI that you can tune electronically. Of course you will need a good, tight engine to start with.

There is another Canadian here on this forum that's getting 24 mpg with his BBD.

Post a picture of your hoses and what they are attached to, maybe we can figure something out.

anything like this? :


This is an 82 vacuum diagram.:



I have an 80 with all the pollution stuff attached. May that will help.

[86cj74.2L]

It's a toss up.

There is a "what mpg do you get" thread and most all tell you their milage and rig setup. I.E engine and carb.

I'm partial to the BBD. I know how it works. Know what goes wrong with it. Know how to make it better. It does have its quirks. Every BBD basher here will gladly point them out to you.

If I was forced to chose another it would be a toss up between a MC 2100 or a holly 2 barrel.

Would I buy a weber? Hard to say. If I found one in the junkyard or was given one I'd take it. But I need something with no quirks. Onceset up I'm sure they have none. But the "how to set up the weber carb" thread has a few 100 posts.

My mother in law is 66 and it just needs to start and run. Hot and cold, winter at 8 degrees f all to way to 100 in the heat of summer. It's all she has. And if I experiment and it leaves her sit it looks bad for me. ( and I have to turn around on my way to work to get her running. As well as fix it for her to use in the morning because I work a 12hr schedule. I leave before she leaves to go home and I'm not back home in the morning before she leaves for work)

I'm pretty sure I can get more mpg out of a BBD then the MC 2100 because of the metering rods Since if I understand correctly the MC 2100 is very similar to setup on a holly 4 barrel. as for the weber I can't say.

I have the BBD getting in the mid 17's currently. And I still have the carb hooked up to the computer.

Edit; I'm pretty sure I read most all of the what mpg thread and except for LT1 I'm not impressed with the mpg of the typical fuel injection conversion when done on the 258.