ok i have a question or 2 about the 8ba in my 50 shoebox i was told that an easy way to get alittle more performance was to get an iron 2bbl intake from a mercury which i did it has the 4 bolt carb flange and im told i can run a certain early 60's rochester 2 bbl on it now here come the questions what years was the carb that fits this intake availible i have bought 3 different rochester 2bbls and the bases are all too wide for the intake flange would i have to run a carb adaptor to get the later carb to fit the intake if i can find the "smaller" base from a rochester 2bbl will it fit the bodys i have or do i need to run the whole body? on the intake i have i believe it is also a 1950 on the pass side of the intake below the carb flange there is a steel line that screws into the intake ...what is this? can i just put a plug in it? and on the driver side of the intake below the carb flange there are a series of holes on a flat machined serface ...what are they? and can i just plug them and im tryin to build my shoebox as a "hopped-up" car that a kid just out of high school would of had in and around 58-60 this is why im not running an aluminum intake or heads unless i paint them to match the engine to "hide" them (but it will have a few later updates that dont meet the eye) i.e. 12v and electronic igntition also i have a set of headers for it and im going to be buying some 80 inch lakepipes which im planning on actually hooking up with out any mufflers are the pipe diameters a good size for a flathead meaning will they give enough back pressure without choking the engine i know this car isnt gonna be a road rocket by any stretch of the imagination i just want have afun little car to cruise around in
The later ones were larger. You need something that came off a 283....'50s-'60s. The ones you have probably have a seven-digit number on the side that starts with "7". They're too big. DD
That steal line on the bottom is probably your vacuum advance, or whats left of it. Research the Carter two barrels, You can run those on some pretty big inch flatties and get good performance.... Cheers and beers Hodge
the steel line im refering to is about 3/8 diameter so i dont think its a vacuum advance line and im not sure a 50 flatty has a vacuum advance on the dizzy need to go out and look thanks guys for the responces soo far
that steel 3/8 npt fitting is a vacuum line for the wipers. the advance line went into the carb base.
You are never going to notice the difference on the street with that carb. Your Holley will be just fine. If you change the carb, you will have to change the distributor to something with mechanical advance. Check with Bubba's form Indianapolis.
My 51 flat 6 has a vac line coming out of the carb base going to the dizzy, 3/8 is def too big for advance...My wiper vac line is 3/8 and does come out of the manifold close to the carb....HTH Cheers Hodge (hey post a pic of that setup just for grins....)
i am going to be buying an electronic dizzy from speedway ...yeah im on a budget bubba has never responded to any of my pms thanks johnny bondo
drunkandgreasy yeah i went out and looked at my engine it does have the vacuum advance sometimes im a dope
also, you want cheap power, weld up a little "y intake" and bolt the two carbs on-top of the stock manifold. or if you wanna get crazy weld or braze it in place of the pad the stock carb bolts too, and paint the intake aluminum. OR buy an early aluminum intake, some aluminum tube and flat stock, weld it all together grind it all smooth use the welding rod to fill in areas ect, grind that smooth. then sandblast the whole thing with heavy sand. itll look just like a aftermarket speed part lol then you can mill the heads down a little. THEN you could maybe put some "pop up" style pistons in it if you wanted to get real on the inside. some cheapy headers..... thats the cheapy ways. putting a merc crank in it used to be cheap, but everyone bought those up like crack rocks, and now want to sell them for diamond prices to fund there raging ardun OHV addiction.
ahh I can,t believe that 2 carbs on a y manifold will help anything. If so why not use 3carbs? Using a larger 2 bbl carb makes more sense, and would be what I would,v used baknthdayd. The 2bbl manifold could stand a little boring out for the bigger carb.
'57 Ford etc, Your Merc 4 bolt manifold is missing parts, making it look odd. First, the angled tap directly under the carb base is threaded for the vac wiper hose barb. The metallic pipe coming from the right angle fitting near the manifold base on the passenger side is actually routed from the air cleaner and is a filtered air inlet to the choke heater pipe running crosswise inside the manifold. Those various holes and mounts on the driver side of the manifold are the other end of that pipe and are for the choke operating module (missing), which uses metered manifold vacuum to draw heated air from the choke heater pipe into the spring chamber of the choke cover and cause it to operate a rod linked to the choke shaft of the carb and provide cold start mixture enrichment. Venturi vacuum fittings are provided on the carb to operate the distributor advance system. I recently fitted the exact manifold to my '49 Merc rebuild. The carb I used is the Rochester 2GV, with a Mallory dual point mechanical advance dist.
Edelbrock didnt just stick 2 carbs on a single carb manifold, look where the Y is attached, it actually has more open area than a 4 bbl.
As stated small block Chevys used the small based Rochesters until approximately 1969. So you can verify it will fit, the small base Rochester bolt spacing is 1-7/8" by 3-1/4".
I'm running an early 2g on the flathead in my F-1. Make sure the ports in the manifold match the throttle bores in the carb.......also you may have to run the carb backwards for the stock linkage to hook up. These carbs work good on a flathead and are dead reliable....
i think these guys have it covered ,i pulled my stock heads and had them plained down for more compression [cheap] made a world of difference.
I always turn them over and look for the very distinctively shaped exhaust heat riser channel that runs from side to side along the top in this picture. No ruler required and I'd forget the dimensions anyway. The newer carbs are very different looking underneath. If it has this shaped channel it's an early model and will fit the Mercury bolt pattern. Never trust a vendor that is trying to make a sale.
will the smaller base fit the larger body? im thinkin it wont thanks guys for the very informative replys
This is what my flattie model A will be. I'm running a stock manifold, 3-bolt pattern, not your 4-bolt pattern, and a Y intake. I'm no historian, but from what I've read these Y intakes where made by a bunch of people, and surely may have been what some high school kid bought to try to hop up his car. I'm running 94s, which have a vac line going to the stock distributor. For now, I've got one carb blocked off, so the vac signal is the same as it would be on a stock single carb intake motor. My car's not done, but the flattie does run. Sure, it's probably not the way most would do it, but it looks awesome to me, and it's way cool. And it'll run good, and be fun to tool around in. Some day it may change, but for now, it's cheap, I could afford it, and it's cool in my book. Pete
I would question how fresh your motor is,to start with. If your motor is like a lot of ol flatheads,you can gain a little power from a good ring and valve job. Read the book by Ol Ron or JWL ( Flathead Facts). They have a lot of good info back by Dyno test. JMO
I'm curious as why there wouldn't be any noticeable increase in performance. I am planning on doing this on my '51 Ford. I see where it would be important to enlarge the throttle bores to match the carb, but that seems easily doable. I have a couple of Mallory distributors (an old style one and a new style one) which I am planning on using; I'll put them both on and use the one that works best, or the old one if they work the same. I plan on milling the heads .050 as well. I already have a set of Fenton headers on the car, so I would expect to see a difference. Some one above said they had good luck with a 2GC on a flathead. I have them in several other applications (e.g. the hemi in my avatar) and have always been happy with them.
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