I am work on a tri power set up using Rochester 2G carbs and have some questions. I have a good tech drawing to help with part names- . link to tech sheet - http://www.surplussales.com/Automobile/Carburetors/pdf/ato-77-770a.pdf . Q1 - I have been looking at some set ups and noted some parts not fitted. One is Vent Valve parts - (9, 10, 11). Qis the rubber part underneath still used? Q2 - are all choke parts removed from the 2 outside carbs, including the choke plate and shaft? Q3 - parts that need plugs - the 2 holes were the choke shaft goes thu the carb body. The vacuum port on the base. the Idle adjustment (52,53)- the vacuum take off that operates the choke. Could I use the Idle Adjustment screws (52) to seal off the base- cut them down, discard the springs and use some lock-tight? Q4 remove the power valve parts (33,45,46)? Q5 best way to get get the end carbs (bases) to seal when closed. The after market one are pricey. any thing else?
gm used a product called dag213 to seal the secondarycarbs butterflys from the factory product still available at pontiactripower.com see that site for all your parts &info................
Somewhere on here is a post that I did on lapping in the thicker replacement secondary butterflies. It's pretty old now and I talk too much so it may be hard to find. You can buy the bases already done but I just enjoy doing it myself for myself. You can do it too if you want to.
http://www.jalopyjournal.com/forum/showthread.php?t=459068 http://www.jalopyjournal.com/forum/showthread.php?t=216531&highlight=cleaning+carb+bodies Read Read Read
rem: plug power valve holes on outers all the carbs have a vent tube in the center of the carb screwing the air screws in does not plug
There are kits on the market to convert the 2Gs to tri-power. They have the thicker throttle plates, long throttle shafts, plugs, springs, gaskets, everything you need to do the conversion. They are rather costly, but well worth it. I restore carbs and have done it both ways. The kit just makes a nicer set-up and you don't have to try to find stuff that will work. I know Charley Price - vintageparts.com has them and I think I saw them at Summit. There are also bases that are already made up that you can purchase. If you don't want to worry about sealing etc.
Are there any good shops that rebuild/refurbish 2G's? JET performance looks like excellent quality but their 2G's are a little too hi-po---i want stock for now. Also the JET carbs appear to have no choke.
yep, I'm up for laping in new thicker butterflies. as far as vacuum holes on the base - the large in the center. a small tube just above it (vac for choke pull off?) also 2 tiny holes just in from the base bolt holes.... whats this port for?- . ok should I assume all holes on the base that will allow vac are to be deleted? the to tiny ones near the bolt hole are above the buterflies- so no vac when butterflies are shut. the idle adjust screws allow air into the hole in between the butterflies (and below, is fuel also present at this place? - the screws control air in to suck a small amount if gas supplied by the power valve up a little higher? power valve is not used on secondarily s. am I on the right track??? ... .. .
Never assume that the location of a hole determines what kind of vacuum that it supplies. That port with the arrow is where the factory connected their vacuum advance and even though it is high on the carb body it is in fact manifold vacuum. Once you get the carb apart spray some gum cutter in there and trace where it comes out. You will find that it goes straight down into the carb base plate and is open to the manifold side of the butterflies. It will have to be plugged or the engine won't start. Yes the power valves on the secondaries get plugged too.
Power valves are 5/16-24x1/2, a nice button head allen and gasket solves that. jets and small parts can be sourced at walkerproducts.com or check with HAMB vendors.
Thank you for the walkerproducts.com link, a good place for all those small parts. I'm looking at how to build a progressive linkage - using the existing throttle levers. anybody done this?
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