390ci - Should I get a new carb or a carb/intake manifold combo? Feels pretty weak down low. I have some more tweaking to do before I make any purchases.
Does it feel like it is weaker than stock down low? I always like to start my search for power with basic tune-up junk and timing before parts. Are you running all-stock now, or what modifications/parts are you running?
Haha.... I guess it's funny you say that because I have NO CLUE what it should feel like. I guess it just feels weaker than I like. Yes it is all stock. Basically everything that is bolt on is new besides the distributor (cap/rotor/plugs/wires). A timing check is a great idea first,then some slight tweaking on my carb (newly rebuilt). Then i'll see where i'm at. Thanks!
I would start with a va*** gauge and set the carb. and timing first. A va*** gauge takes the guess working out of of setting the timing and carb. up right. Just my two cents. Jimbo
Is it in a rod, or in its original location? As much as a '59-'63 Cadillac weighs, it's not going to take off from a dead stop like a '60s musclecar. For low end power, I really don't think that you'd do better than the stock AFB setup.
Lot's of old car's suffer from timing chain stretch and old nylon gears, which screw's the timing all up as far as performance goes. You'd probally be better off just adjusting it for now.
I don't know all the intricacies of these Caddy motors but here's some things I'd take into consideration. *Mileage of the engine and general mechanical condition and tune-up. Good compression? Good valve and ring sealing? Were Caddys prone to stretching timing chains or jumping cam timing? *As mentioned above, vehicle weight and axle ratio. The engines may have been powerful, but they had to be just to move an extra 1,000 lbs. of car at highway speeds. It could have a pretty tall gear in the back to try making at least slightly better mileage. *Transmission type and condition. Is it maybe starting out in 2nd gear instead of low making it feel sluggish? Some Hydramatics byp***ed the fluid coupling in third or fourth gear going into a direct drive mode with no slippage. If this happens too early it can bog things down. Also, if it uses a fluid coupling instead of a torque converter you won't get any torque multiplication. It makes for smooth operation but it won't exactly snap your neck when accelerating away from a stoplight. Before you dig too far into the engine make sure you've got a reasonable idea of just what you can expect in return for your money and efforts. Maybe find someone with a similar car, engine and trans combo who can give you sort of a baseline of what you can work towards.
Ditto on the tuneup. After that I might consider doing some exhaust work, lots of the old cars I have bought have had junk restrictive mufflers on them that were old.
My 60 Coupe was a dog when I got it. Changed the carb to an Edelbrock 1406 600cfm added Pertronix, dumped the points, and it ran great. Trans kept blowing front seals and had it in and out a dozen times. I finally put a 700R with the wilcap adapter and it was Day and Night -- REALLY woke the car up, fast off the line and almost idling at 60mph Seemed to have unlimited top end, but that's where these boats get squirrely....
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