dual 4 barrel carb

[Kim K Kaiser]

I was watching one of the car rebuild shows the other day and they kept talking bout putting 2 carburetors in the thing,,,and were would you put another carburetor...,,what would be the purpose,,  

would that work on the 63 64 cadillacs???    it does seem that getting one set properly can be  a sometime challenge, how wold you get two to work ... 

[3ft7bqmb7dryo]

There is no setup for the 63 and above to run dual carbs. 62 and below have an take manifold so you can run dual carbs.

Running dual carbs is more of a status statement with Cadillac, than it is with performance.

[Jason Edge]

Not getting into the pros vs cons of multi-carb set-ups, but this did trigger some thought I had on this way back on multi carbs on the 63/64 Cadillacs.  
In the 1966, 67 and 68 Master Parts Book parts group 3.265 the intake manifold for single carb applications have a different intake manifold from 59 to 62 (part # 351 2079) vs the 63 to 66 intake (part # 363 2870), yet in the 1969 Master Parts Book it lists 59 to 66 as the same intake part # (363 2870). I know the cylinder heads have the same mounting areas since the 1958 to 1963 heads were the same, however, I also know the engine block physically and dimensionally changed between 1962 and 1963 with the core block reducing length and height. I don’t know if the core block change altered the relative position of the intake on the heads and if it would be a straight bold up, but it seems going with the 69 Master parts book you can use the earlier multi-carb intake manifolds on our 63/64 Cadillacs.

Of course you would have a lot more work cut out for you in terms of accelerator linkage, fuel lines, air filter(s), etc.  If you were after all out performance the EFI and fuel injections options should produce the best power and performance gains, however, for Old-School Cool it would be neat to see a dual or triple carb setup on a 63 or 64. If someone knows for sure I would like to know so I can update my notes.

[Kim K Kaiser]

Understand,,,, i hv NO interest in pursueing such an endeavor,   i was just curiuos as to what it woukd provide you.   Is it power?  Engine rumble?  Im guessing not fuel ecomomy, so as Russ mentiined,  is it just a cool factor ...  and normally, on the drag race tv shows,   i dnt see too many 5300 lb caddys toeing  the line for a drag race.it seems the shows either flaunt the dual 4 bbl. Or the new FI systems on the older 60s and 70s restorations.   

[Jason Edge]

A properly designed and tuned dual carb setup can provide better fuel distribution and performance since the carbs can more evenly distribute the air/fuel mixture down the length of the engine cylinders.  If combined with a tunnel ram or hi rise intake is can also provide better fuel dispersion.  With a dual carb set-up you will run considerably smaller CFM rated carbs. For example if you were running a 850 cfm single carb you might run a pair of 450 cfm carbs on a dual carb setup. With a 750 cfm carb, you might run a pair of 390 cfm carbs.  Of course everything has to be dialed in perfectly to really take advantage of the potential of a dual or tri-carb setup.  There is a lot more up front cost and setup to consider, not to mention the additional maintenance of keeping multiple carbs tuned.   Of course multi-port, and direct port computer controlled fuel injection takes this distribution tot he extreme … but there can be some advantages of an 2 or 3 carb setup over a 1 carb setup since the questions was asked.
There is also the COOL FACTOR. It just looks cool to some of us old timers to see the 2 or 3 carbs sitting up there, especially when they are dialed in perfectly! If you want all out performance, look to fuel injection; however, for around town "cool as Fonzie" cruising, the dual carbs would look great...and could perform nice if set up correctly.

[3ft7bqmb7dryo]

I have a pre 62 dual carb intake. I'll have to see if it fits the 63/64 engine assembly.