Unfortunately I don't have any spare carburetors, so I have to buy something. There are a lot of BBS variants out there - is there a chart somewhere that says which ones have PCV, automatic choke, etc? Some pictures show some vacuum ports but I can't always tell what I'm looking at.

I thought you'd narrowed in on a 6218s, which would be a very good candidate.

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Too many people who were born on third base actually believe they've hit a triple.

Well, that one is by far the most expensive. I wouldn’t hesitate to spend the bucks if I knew it would work, but I’m still troubleshooting at this point.

The 1974 Holley 1945 is notorious for being junk no matter how much fiddlefutzing one does with it.

The 1973 Carter BBS is notorious for being quite good with no fiddlefutzing required.

Nice new motor…junky old carb…I don't get it, but you do you!

¯\_(ツ)_/¯

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Too many people who were born on third base actually believe they've hit a triple.

http://www.slantsix.org/forum/viewtopic ... heavy+duty towards the bottom of that page you'll see a listing for Carter carburetors I believe that's the heavy duty emissions carburetor used D200 300 trucks. Which means bowl vent open air, and no canister purge port.

Oh my.. That may be a wonderful carb.. but it requires a whole bag of gold coin.. IF that is the price of a carb these days... I would start looking at EFI as an option..

Rich006, where do you live? Maybe there is a forum member near by who has a known good carb that you could try.. Then you could make what ever purchase decision you want with confidence.. Or just keep your eyes out.. as BBS carbs can not be that hard to find. OR post in the wanted section...

{edit} Ok I just looked up EFI prices, and that new carb is thrifty in comparison.. Still 4 bills seems like a lot of coin.

Matv91, you win the research award! I see the two old threads with posts from MitchB about drilling out the power valve restriction in the 1945. I think you're suggesting I could solve my problem by opening up that restriction. My 1945 has the California power valve with the rod that mechanically overrides the vacuum control at WOT. I don't know why that was necessary, but maybe it's because the valve is calibrated extra lean, that is the restriction is extra small?

I am thinking for now what I'll do is get an AFR sensor and have the muffler shop install the bung while also enlarging my exhaust from 2" to 2-1/4" to the muffler.

for that much as is being asked for that BBS carb, you could buy the NOS BBD in the classifieds and have enough left for the Super 6 intake it would take to get it mounted to your engine.... or mod the 1 bbl intake you have now for parallel mount..... I don't think I'd pay $450 for any 1 bbl.

I don't know why I didn't think to look in the For Sale board! I wanted to get my 1bbl setup running as well as it can before I make any more changes, but maybe I've already done that and it's time to cut bait. I see a 1976 Valiant 2bbl being parted out, and a 1978 Super Six seemingly with all the needed parts. I'm not sure which of those is an easier install in my car.

There were no '76 Valiants with factory 2bbl, so that one you saw (I saw it too) has had a Super Six swap. No way to know how good or bad of one, but also no way to know how good or bad the parts on that '78 are.

I agree that a (good) 2bbl setup would be a better investment than a better 1bbl carburetor.

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Too many people who were born on third base actually believe they've hit a triple.

sure made a noticeable difference to go to the Super 6 on my kid's 80 D150.... Super 6 intake, and a stock exhaust manifold, hogged out with a die grinder (just on the "exit" side/ nothing was done to ports themselves) to the ID of the flange gasket. he has yet to replace the hodge podge exhaust (which is from PO, as he bought the truck) to match the diameter of the manifold outlet. (2-1/4")

and that improvement was measured by the butt dyno, over the "good" 1945, that I had to loan him from my truck when his truck laid over in the parking lot of his wife's work....
and my 1945 was a big improvement over his original 1945 with its worn out throttle bores and all....... it had gotten to a point of "barely ran" with its original carb.
the super 6 is worth it. As I was acquiring parts to convert both of these trucks to a Super setup, I stumbled across a seller that had several "new in package", "Tomco" brand OE style electric chokes on Ebay, I got 2 of those..... and the "correct" choke lever that the choke attaches to for a slant 6 vs a V8 came from Ebay as well.... the 1st is working fine on the kid's truck.....
I ain't driving my 85 yet.... the closer to winter we get, the less likely it will get plated (license) in 2020..... I dont want to drive it in salt season. so do I put my other super 6 setup on it now or save it "fresh" for the engine currently in machine shop jail, that is going into this truck.....

now back to your post..... trust me though, the "Super" setup is definitely worth it.....

See here for a pictorial.
Ebay scores are fun, but you're much(!) better off with an electric choke kit (№ 1232 for use with a 2bbl carb). Unlike the factory choke setup, these are adjustable.

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Too many people who were born on third base actually believe they've hit a triple.

I never had much joy with the adjustable choke on my 1945, which is not to say the choke itself was bad but it might say something about my carburetor. I spent a year or two fiddling with the adjustable choke, never getting it to open at the right rate. I now think maybe the reason I could never get it adjusted right is that the engine is running lean anyway, and so it always wants more choke than it should want. Even the factory choke opens up "too early", with or without the electric assist connected. There's a stoplight about 3/4 mile from my house. In the morning, after that light turns green, I have to use a pretty light foot to avoid a bog-down and backfire.

(Side note: the reason I finally gave up on the adjustable choke is one day it stopped closing the choke at all. I found out it had quickly and completely corroded when a pinhole radiator leak sprayed a perfectly aimed stream of water on it. The pinhole self-sealed with no action on my part, and never came back. I reinstalled the factory choke control and drove like that for another year or two, then I had the radiator tested/brazed while I was rebuilding the engine. Now I have the waterless coolant, so no more high pressure in there.)

Lookee what I found! My local parts yard had a 79 Lebaron with Super Six. I got all of it for $200, less than half the cost of that NOS BBS on eBay. I also got my new AFR sensor in the mail, so I'll get that installed and take some measurements before I do anything else, but there's no doubt I'll be installing the 2-barrel setup.

Initial questions: What's the sensor just downstream of the manifold vacuum port (and why is there a wire attached to the vacuum port)? And what's the part on the red rag, that was bolted to the center of the cylinder head? Looks like it has 2 electrical connectors. (It's what the guy pointed me to when I asked about an EGR vacuum amplifier--it's clearly not that, but he said it connects to something in the exhaust).