I understand that qjp was good at one point.. I wouldn't what to put a Todays built QJP carb On a NEW motor...... GOOD BYE camshaft.....
A 70 carb does not have a charcoal can port even on California car. Vacuum hose went to the air cleaner on a 70 California car. 71 has the port for can.
Agreed. the original carb... He must have received a newer 75-79 from qp. I dont for sure when they buick started using the charcoal can.
We can't be sure of anything until the OP updates this thread. It sounds to me like he connected the canister to the PCV vacuum port on the baseplate, and if that's the case, it will never idle because of the massive vacuum leak. I suggest we wait until he gets back here again. It might be awhile. No sense in speculating until then.
I agree OP does need to make updates.. Although The first POS carb I received for my 67 sky 400 was a 75+ from qp. one of those 1705**** with the choke built on the carb by Rochester.
Agree, as said before there is nothing on that baseplate to attach a vacuum on a 70 except that huge PCV port
1971 model year. 1970 California only model year I think it depends if the car was built in California.
No special California Carb in 70. Many California Emissions cars were built in Flint. My GSX was one of them. It had an elaborate emission venting system. I rebuilt the entire system. It used the same 4 speed Carburetor as other state models. I don’t think there was a California only carb for other models but I will have to look it up.
Wow, Thanks for all the replies. Going out to the garage in a couple of minutes. To clear things up, the original carb was from a 70 Riviera and had no port for the vacuum canister. The canister was damaged and not connected to anything but the fuel line from the tank. My rebuilt carb is a correct casting number for a 71 and has the port to the right and below the fuel line. I had picked up an unbroken canister at a swap meet and did hook it up. I will plug that line and see how it runs without that connected. I have also picked up a vacuum gauge and will use that to set the mixture screws. My problem was I could not get it to idle well enough to even begin to think about trying to set idle mixture. If it still idles bad with the canister disconnected, I will go back to QJP and go from there. They have been very responsive to my e-mails so far. I do have a 71 service manual, but the car is a combination of parts, so it is not always what I need. Will update later or tomorrow after I have a go at it.
You have to plug the vacuum port at the carb. Not the hose. The line from the charcoal can does nothing. The engine does not care if that charcoal can is even there. The carb creates the vacuum and sucks air from the can. The can does not make vacuum. Get some small vacuum caps to cover ports in carb for testing. You can run a vacuum line directly to a port on the carb from the distributor if you need vacuum advance. There are two. One is full time vacuum the other just off idle. You will get arguments which works better. If carb has lots of advance built in to it you don’t even need that. Plug all the ports in the carb except the big PCV port in front. See how it runs then. I highly suggest you find a 71 455 carb from a 71. They were bigger carbs than a 70 and made for the lower compression 71. They were also jetted much richer.
Now here is why you can’t run the charcoal can I just realized. This is the correct 71 455 routing. Look at the pencil. It is pointing to the baseplate port where the hose from the charcoal can should be attached. The 70 carb does not have that so you cannot use the can because the port is not there on a 70 carb. You can’t run it to the air cleaner like a 70 California emissions car because that requires special parts
For general information here are the 70 4 barrel carbs. There were no specific California carbs in 1970.
Dave have you ever driven that car on those dirty a Massachusetts streets. Damn that engine is tooooo clean
