This was the 1977 nitrous 2 barrel!

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Rick, you are a wealth of technical information!

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Hyper_pak

What year did these Carter BBD carbs start having the extra housing above the accerator pump plunger?

I'd like to know more about what's going on inside that housing. The step-up rods seem to be moved by a cam inside that housing directly by the throttle linkage (the same link that operates the plunger). When the plunger moves down, the rods move up.

In earlier BBD's there was no such cam, no such extra box arrangement around the plunger. Instead the step-up rods were moved by a piston by vacuum?

I'd like to know more about this difference as to how the step-up rods were moved, and was there a performance improvement here?

Also, are the rods and jets larger on these newer-version BBD vs the older ones?

Buy this one and you can figure it out!

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Hyper_pak

I did buy this:

https://www.amazon.ca/Dromedary-MB-172- ... B07CNPCQBW

I just want to know what year that style carb came out, was it used for all 318's and slants when it came out?

Be wary of the Chinese wanna be anything.
The "tin top" came out about '74- '75ish.

This document: http://u225.torque.net/cars/SL6/docs/BBD_Manuals.pdf

Combines two documents in 1 file. 40 pages in total. The first document is "BBD-1 1/4" Service manual. About 26 pages. It's a Carter document. After that is this document:

Chrysler '76 November Reference Book
Two Barrels for Six Cylinders

It's about the Super 6 BBD carb, which I guess came out in 1977.

They go into detail explaining the difference between this carb and the pretty much identical version for the 318.

The stand-out differences to me are:

- brass plug insert with drilled hole above the mixture screw to limit fuel flow (throttle body restrictor)

- some small tweak in the step-up piston lifter tab and the width of the piston stops (slightly less free motion range in the super-6)

- main venturi is smaller in super 6 (1 1/16 inch vs 1 3/16 inch for 318). I would have to take a few carbs apart to see where they're making this measurement.

What I find VERY INTERESTING in this document is that they say nothing about the step rods and metering jets being any different with the Super-6 BBD and the 318 BBD.

The aftermarket china BBD carb seems to market itself as both a 318 carb and a Super-6 carb but the Chrysler document says there's differences between them (which is understandable) but the differences to me seem trivial and the only actual important difference is the size of the venturi (because they say nothing about rods and jets) and I can measure the china carb to see what it really is.

The diameter of the barrels for this china clone carb and various real BBD carbs I have are all 1 7/16 inch - not 1.25" or 1.5". So explain to me why I come across references to 1.25 and 1.5 inch BBD? What are they measuring? I don't get that.

And also the hokey term "solid fuel". What - are they freezing the gasoline somehow to make it solid?

Correct me if I'm wrong - The "solid fuel" term or idea comes from the venting of the accel pump well to allow vapor to be released leaving LIQUID (not solid) fuel in the well. If the carb has the boxy extension on the air horn -> does that make it the "solid fuel" type of BBD?

I don't remember details but I remember reading about the "solid fuel" thing somewhere pertaining to all but the earliest of the thermo quad which is also a Carter carburetor

They claim that the 1976 - 77 318 throttle body did not have channels cut from the intake-side into the curved channels on the bottom surface. But the "new" super-6 BBD does have them, and hence the gasket doesn't need the notches.

What year did these Carter BBD carbs start having the extra housing above the accerator pump plunger ? 1974 first year for tin top solid fuel carter bbd.

I'd like to know more about what's going on inside that housing. The step-up rods seem to be moved by a cam inside that housing directly by the throttle linkage (the same link that operates the plunger). When the plunger moves down, the rods move up.

In earlier BBD's there was no such cam, no such extra box arrangement around the plunger. Instead the step-up rods were moved by a piston by vacuum?
Metering rod arm puts metering rods in correct position for that throttle opening, vacuum piston controls rod position between rich and lean stops.

viewtopic.php?f=19&t=35294 Long post about this stuff

I'd like to know more about this difference as to how the step-up rods were moved, and was there a performance improvement here? Better air fuel ratio control,worked better than just a spring. Mpg drivabililty and emissions all better in my opinion. Wide open throttle with right spring not much difference.318 small carb might still have enough vacuum at full throttle to prevent rods going full rich.

Also, are the rods and jets larger on these newer-version BBD vs the older ones? Completely different both jets and rods.

I just want to know what year that style carb came out, was it used for all 318's and slants when it came out? 318 74 slant 1977 by 1977 all carbs had slots no need for notched gasket

Rod and jet and orther info down load all 3 lots of info http://www.tocmp.com/manuals/Carbs/Cart ... index.html jet size varys with venturi size slant six cars most trucks .086 jet, 318 bigger jets and different rods