crappy throttle response, hesitant

[jds1971]

Raise the float level and test drive it on the freeway to see if the stutter goes away- that may help your low end problems, too.

Joe

[71-F-250SC-72-F-250C]

The points condensor has also been replaced.

[Commodore Woods]

I can hear a vacuum leak but the gauge say's it is running fine

Don't know if this would apply or not, but I know on my '72 390 I've got a bad vacume leak around the main rod in the Carb, old bushings. Maybe check and see if you've got any play in the rod?

[68F250]

You definitely have a vacuum leak somewhere, I'd put money on it.

Take some starting fluid and while the engine's idling spray all the vacuum hoses, fittings, carb. base, throttle shaft, even around the intake to head surface. If the engine picks up speed you've found it. Don't stop at the first one. Be very specific on what you spray, don't go fogging. The carburetor will suck it up and give you a false indication.

Also, disconnect and plug the vacuum line that goes to the vacuum advance. Do you have power brakes?

[Faithful Old Road Dog]

Like JDS, I would check the float level or fatten up the mixture by changing the jets. I'm not too faniliar with the 2bbl, but it definitely sounds like lack of fuel.

Come to think of it, when was the last time you changed the fuel filter?

[71-F-250SC-72-F-250C]

I am gathering up all these suggestions, and plan on testing them this weekend. I was thinking a lack of fuel also at first, and tried changing the jets, but the guy said if I found some jets that would fit in that carburator, to give him a call because he has been looking for years. My only other option with the jets would be to drill them out, which I am not comfortable doing. Also, if it is a lack of fuel, then that can be adjusted out, unless the carburator is just to small for the engine. I know there is a vaccum leak somwhere though for sure, just a matter of finding it. But do you guys think 350 cfm is enough for that engine?

Stephen

[Faithful Old Road Dog]

Lot's of V-8's run on 2 bbl carbs. I wouldn't worry about cfm's unless you're looking for more power!

[Jonathan Rickman]

Personally, I do think the carb is too small, but that is not the source of your problem. In general, smaller carbs provide better response and often give the illusion of more power.