carb replacement/repair (long)
Your wrench oughta fix the sticking chokes, but you oughta make sure that's really the problem. But I don't know your wrench, so I'll take a couple shots at things that can cause high idle. Nor do I know your level of competence.
Improper ignition timing can raise the idle but not usually up to 2500. Static timing at TDC will put you real close to correct, assuming no excessive slop in the diz.
There is a single screw on the horizontal portion of the carb linkage, just forward of the fuel pump, that will raise the idle if screwed down too far. Find and check this little screw, make sure it's not the culprit.
Next, if you can re-synchronise the carbs (it's not hard) you can back out the idle speed screws, equally, about 1/4 to 1/2 turn, on both carbs. Maybe that's all it is. If this doesn't lead to happiness, run the idle speed screws back where they were. Maybe the idle mixture is off but you gotta have some practice and confidence to do those correctly.
Next, the linkage rod that's nearly vertical, coming up from the bellcrank on the left side of the block, may be incorrect length. Check by disconnecting that rod where it meets/mates with the horizontal linkage mounted on the manifold. If the idle rpm doesn't change, reconnect. This happened to me...
Maybe only one carb is way outta line. Disconnect the short vertical link on the rear carb so they operate independent of each other and see what happens. If no change, reconnect.
A large vacuum leak could raise the idle. Make sure the intake system is properly connected and there's no obvious intake leak. Run the car, disconnect the hose to the brake vacuum booster and plug the portion running to the intake manifold with your finger. No change? Reconnect. Change rpm? then there's a leak there, either in the hose, or the booster somewhere. This would likely also weaken your brakes, not a good thing.
Wow, see how many ways there are to go wrong? And there are probably some other potential things I've forgotten...
The most common carb replacement pattern is two Weber 32/36 carbs. These will cost you some (some say a lot) top end power, but are supposedly more adjustable, easier to drive a low speed and give better gas mileage.
Another carb option are a pair of Weber 38/38 carbs which have both barrels on each carb opening at the same time. Gas mileage goes down, power is there.
Triple Weber 40 DCOEs are racing carbs and EVERYTHING on them is adjustable. Though some have 'em working quite well, most setups will suffer from lousy gas mileage. Why put on three carbies if you're not going to be stomping on them every little while? Um, expensive too. Linkage, intake manifolds and water neck have to be customized. While you're at it put in a cam and really burn the fuel.
If you're full gonzo there are aftermarket fuel injection systems; some toss out the carby motor and go with L-jet or Motronic.
Maybe we continue this offline...
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