Tuning Weber 32/36 on a 2F

[nabbasi]

I replaced the weber 32/36 that was on my 2F when I got it with a Fuji from cityracer. Along with an OEM fuel pump, distributor, plugs, plug wires and fuel line, it’s a huge improvement with everything from starting to keeping up on traffic to climbing hills.

 

[Grayscale]

In my opinion, the 32/36 is for a 2.4L. The 2F is a 4.2L. The two engines produce similar vacuum, about 15 to 22in-Hg. The problem is getting the volume of air/fuel-mix for your engine thru the ventuir (narrowest point) of the carburetor's primary barrel.

 

[RevISK]

Y’all are missing the assignment.

We’re looking for a solution USING the Weber.
Everyone knows OEM is the ticket or even a 38/38.

A 32/36 can work according to several of the wisest mudders as well as a few non forum members.

Mine was behaving amazingly this evening, I just don’t know why.

 

[nabbasi]

Y’all are missing the assignment.

We’re looking for a solution USING the Weber.
Everyone knows OEM is the ticket or even a 38/38.

A 32/36 can work according to several of the wisest mudders as well as a few non forum members.

Mine was behaving amazingly this evening, I just don’t know why.

My friends are all jeep guys, and they weren’t sure why I was going through the hassle of tossing a perfectly good carburetor.

 

[fireflyr]

Here’s a screenshot of a conversation I had with another member. It may help. Then again, it may not….

I ran a 32/36 for about 15 years. It was nice after I jetted it. The F.5 was bored .40 (?) over and I was running a header.

 

[RevISK]

Awesome, thanks @fireflyr

 

[RevISK]

Alright, because I said I’d come back…

Typical, 32/36 falling on its face in the mid 2,000 rpm range, right? That’s why you’re here?
My truck ran fairly close to what I think could be perfect with my setup this summer at elevations of 8,000-13,500 with just some advance and upping the air correctors 1 size.

Got back to 650’, threw the old correctors in and it’s running like hammered dog dook.

This tells me something… I’m running lean.
I pulled the plugs and yeah, muy lean.

I only had one jet larger for my secondary and it made a difference.

By the time the jet kit gets here so will the Fuji carb from city racer and I can finally go full office space on the Weber. But, I am a dog on a bone and need to know how to make this carb work on this truck.

A picture just FFS…

 

[brian]

Glad to there's a fuji enroute.....you'll not miss the weber.

 

[Grayscale]

This is how I'd tune a Weber. Starting with a 38/38 synchronous, I'd grind off some/most of the teeth on the primary throttle shaft gear. Performing such a mod makes it so the secondary would open about at the same angle as the 2F carb, no longer synchronous. Even eliminating the secondary entirely would be like the early F-one-barrel-carbs. The 2F carb is about 38mm in its venturi, iirc. It is just that the difference in primary-barrel area between 32mm DGV or DGEV and the 38mm-synchronous, or 2F carb is like 1.25-square-inches to 1.75-square-inches respectively. Hence the 32/36 is for a 2.4L not a 4.2L. This way, you are starting with about a similar amount of throttle opening, thru a similar venturi, for the same rotation of throttle lever / accelerator pedal motion. The 2F carb just barely opens up on the secondary when the primary is almost fully open, but that is only if the vacuum allows it to open. After you mimic the venturi needed for the F or 2F, then tinker with jets, emulsion tubes, and air correctors, but, starting too small in the carb venturi will slow the movement of air, not creating enough Venturi-effect, hence the stumble.

I have a never-used, manual choke, 38/38 on the shelf that anyone can have a stab at, pick-up only.

I get the feeling that Webers became popular for carb swaps due to some kind of proprietary-rules history?

 

[brian]

I get the feeling that Webers became popular for carb swaps due to some kind of proprietary-rules history?

they came on the scene right about the time oe carbs were getting to the point they needed rebuilt the first time....pre pre internet. rebuilding carbs is harder to do then exploring deep space, as we all know.... advertised as being the end all to beat all, they quickly gained a reputation .....they gained that rep by running better than oe carbs that needed attention.

 

[Grayscale]

Man-A-Fre once offered an adapter for a Rochester 2G 2-Jet. Downey did the Holley 350 7448. Pegasus describes the Weber 38/38 as 280 cfm. All these options offer less restriction than the 32/36...

I have a synchronous adapter for the 32/36 from Pierce Manifold, iirc, intended to make the secondary to open with the primary, making the carb do more work without as much restriction... I wasn't impressed when I installed it on the bench. I don't remember it being actually synchronous, there was some slop between the two throttle blades, maybe it is supposed to be that way.? Also, adjustment of the secondary idle requires a set-screw only accessible when the carb is off the truck. Maybe I should have tried it out?

Perhaps reasons for going aftermarket, skipping a rebuild, are damaged fuel inlets on the F-carbs, or lack of an air cleaner assembly from previous owners, or a mismatched intake manifold from exhaust heat-riser damage.

I've said it before, why all the 2F-carb-clones, someone should make a 2-barrel F-manifold carb? Or, someone should manufacture a simple air cleaner assembly, and throttle lever that can be used with the 2-barrel F-manifold and the 2F-clone-carb.

 

[RevISK]

Man-A-Fre once offered an adapter for a Rochester 2G 2-Jet. Downey did the Holley 350 7448. Pegasus describes the Weber 38/38 as 280 cfm. All these options offer less restriction than the 32/36...

I have a synchronous adapter for the 32/36 from Pierce Manifold, iirc, intended to make the secondary to open with the primary, making the carb do more work without as much restriction... I wasn't impressed when I installed it on the bench. I don't remember it being actually synchronous, there was some slop between the two throttle blades, maybe it is supposed to be that way.? Also, adjustment of the secondary idle requires a set-screw only accessible when the carb is off the truck. Maybe I should have tried it out?

Perhaps reasons for going aftermarket, skipping a rebuild, are damaged fuel inlets on the F-carbs, or lack of an air cleaner assembly from previous owners, or a mismatched intake manifold from exhaust heat-riser damage.

I've said it before, why all the 2F-carb-clones, someone should make a 2-barrel F-manifold carb? Or, someone should manufacture a simple air cleaner assembly, and throttle lever that can be used with the 2-barrel F-manifold and the 2F-clone-carb.

I have the original Holley carb, 350 iirc, and a rebuild kit that came with the truck. I didn’t put the Weber on but that’s another story.

I’m going to dig that carb out and see if the jets are compatible.

Just got home from taking the genetic extension to his learning facility, this involves some freeway miles. I’ll have to say, the way it’s jetted now, the truck has juice. Still funky in the 2,500 rpm range but once through that area, I had no problems.

To be clear, I haven’t placed the order for the FUJI carb yet or the Jet kit. I have to figure out the transmission in the 62 first.

 

[RevISK]

Alright. Here to close out my contribution to this thread.

I found the solution to my Weber problems, finally.
My truck is running better than it ever has. I figured out the best setting for the Weber that really did the trick to solve all of the issues of mid range stumble, inconsistent running, constant tweaking to get it to run well etc…

In the end it was really quite easy and I should have done this much sooner but I am hard headed and don’t like to be beaten.

So what are those magic settings for the Weber?
The answer: set the carburetor in the box that the Fuji or Aisin carb you just bought came in and try to sell it to someone who could benefit from it. Next, install the Japanese carburetor and try really hard not to punch yourself in the face for waiting to make the switch for so long.

 

[steffan]

Alright. Here to close out my contribution to this thread.

I found the solution to my Weber problems, finally.
My truck is running better than it ever has. I figured out the best setting for the Weber that really did the trick to solve all of the issues of mid range stumble, inconsistent running, constant tweaking to get it to run well etc…

In the end it was really quite easy and I should have done this much sooner but I am hard headed and don’t like to be beaten.

So what are those magic settings for the Weber?
The answer: set the carburetor in the box that the Fuji or Aisin carb you just bought came in and try to sell it to someone who could benefit from it. Next, install the Japanese carburetor and try really hard not to punch yourself in the face for waiting to make the switch for so long.

 

[firefighterjed]

Alright. Here to close out my contribution to this thread.

I found the solution to my Weber problems, finally.
My truck is running better than it ever has. I figured out the best setting for the Weber that really did the trick to solve all of the issues of mid range stumble, inconsistent running, constant tweaking to get it to run well etc…

In the end it was really quite easy and I should have done this much sooner but I am hard headed and don’t like to be beaten.

So what are those magic settings for the Weber?
The answer: set the carburetor in the box that the Fuji or Aisin carb you just bought came in and try to sell it to someone who could benefit from it. Next, install the Japanese carburetor and try really hard not to punch yourself in the face for waiting to make the switch for so long.

I’m glad you resurrected this thread so it could get a proper ending. I shouldn’t have left it hanging. Also faglad that we both ended up with the same solution. Validates my decision. Mines still running strong, driven a couple times a month.

 

[Grayscale]

I keep thinking that if I didn't have the right combo of parts, like an F-intake manifold, I'd borrow the Weber for an air cleaner assembly, and its throttle lever. It should be possible to attach the air cleaner base plate to a 2F carb with the help of 22g sheet metal, pop rivets or small bolts, and a 3.125-inch hole saw? Cutting into the original Weber air cleaner base-plate would help it sit correct. The throttle lever can replace the ball on the throttle of the 2F carb, they are both 8mm with a flat milled into it. You'd need to fab up a cable sheat bracket to bolt onto the Aisan or Aisan-style carb, and make sure it clears the top-mounted air cleaner. I haven't actually done the mod, but, just from looking at the parts stash, I think that it is probably doable.