Hey.... Wanted to change the carburetor of my 54 cadillac. Tried to rebuild my original rochester 4 jet but it's fucked up. So I don't know what other carburetor is the best. 500 or 600 edelbrock? Or other manufacturers? Made oder 40k Kilometers in the last 5 years so I need something that is easy to handle an for a car that I drive over long distances. Sorry for my bad English but I am from Bavaria Thanks for any help. Cheers Nickl
If it was mine I'd go with the Edelbrock 1404 500 cfm vacuum secondary manual choke square bore carburetor using the appropriate adapters. This carb was designed for street motors in the 289 to 327 cubic inch size range, but it has been my experience that a slightly under-size carb will give better street driveability and performance than an over-size carburetor. The reason being that the smaller size primaries promotes higher mixture velocity which is good for throttle response at low speeds and at partial throttle settings. Heres a good reference page from Edelbrock which may help you decide. http://www.edelbrock.com/automotive/mc/carburetors/performer.shtml
Lots of guys like the edelbrock and it is a carb that you can buy new in the box. I like carter carbs or holleys but the edelbrock is a new in the box carb and they work OK.
Hey... Thanks a lot for the link.... there they wrote that it's good for engines like the 302 or smaler engines?
Yes. Please see my whole previous post for the explanation. You'll be tuning for driveability, not peak performance, so you'll not need the flow capacity of a large cfm carb because it will drive worse, not better, in low to moderate speeds and throttle settings than a smaller cfm carburetor would. Higher mixture velocity through the primaries is your friend when it comes to driveability, so in your case, smaller is better. The spread-bore 4-bbl carbs on high performance GM cars of the late '60s combined small primaries with huge secondaries to produce the best of both worlds - great driveability at low speeds and huge performance potential when the secondaries were opened.
The engine is completely stock.... so smaler is better? Did I need a spacer or something or will it fit on the original intake?
In my opinion, yes, smaller is better. The 1404 will work great on your stock motor. I doubt that it will be a direct bolt-on. You might ask da34guy who posted earlier on this thread. Seems he's got one installed on his 331 so he'd know what it would take to get it done.
I wouldn't have edited it out, the logic was good. Nickl, Do not be afraid of the smaller CFM carb on the caddy. The original carb was not a monster and one of the things that I have found over the years is that people have a tendency to over carburete their cars. You will find that with the 500 CFM carb that it runs nice and crisp out of the gate.
Im a big fan of the edelbrock style carb. I wish they still made it with the carter logo. I think weber makes the things. I don't know anything about the caddy carburetor mounting but they sell a sealing plate for when the bolt pattern matches but the manifold has a weird shape that doesn't fit the carb. There like 6 bucks for various venders.
Yes sir a 500 CFM is plenty, my 331 is .30 over with a small Sig Erson cam and will get 20 mpg on the interstate cruisin @ 70/75. Hammer it from a dead stop it'll bark the tires and get a chirp goin into 2nd, It's in this.
Yes a smaller carburetor is better on a stock motor. When they recommend a bigger carburetor, it is for a racing motor or one modified for high speed. On your car the 500cfm model with give excellent performance and better gas mileage than a larger one. The smaller carburetor will also improve idling, smoothness, driveability and all around performance. The larger carburetor pays off only at high speeds. The only place I would differ is on the choke. I would chose the automatic choke model with electric choke.
When your Cadillac was new it was known for getting the best gas mileage of any American luxury car. 20 - 22 MPG on a highway trip is quite possible if you hold your speed to 100 KPH.
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