cluelesscutlass

title says it all. i have a 350 rocket with a four barrel holly carb. on the drivers side there is a screw for the idle. and the passengers side there is a big black wheel looking thing that has tree screws to it and it says lean on it. there two screws in the front that my uncle says are also for air fuel ratio? my problem is that i can get it run idle fine ( although fast) without dieing in drive or neutral. when i put it in gear it wants to die. by the way i havent done the timing with a timing light. any tips to get it runnin smooth.

oldsmobum

The two screws on the front are your idle mixture screws. You will be mostly playing with them and the one on the side which is the idle speed screw.

1, Screw in your idle mixture screws all the way in. Then back each one out 3 full turns.
2. Start engine. Screw in each one about 1/4 turn EACH (it is important that they are even, so any adjustment made to one, must be done equally to the other) one at a time. Repeat until the idle noticeably drops off in speed. Now back off each screw 1/8-1/4 of a turn.
3. Now, adjust the idle speed (screw on the side) where you want it. You now have course adjustment.
4. Repeat steps 1 and 2 and you should be in the ball park.

Another method:

Hook up a vacuum gauge and adjust idle mixture screws to where they pull the most vaccum at the desired idle speed. I prefer to use the first method its definitely workable.

cluelesscutlass

Thanks, ill give it a go in the morning. Do u kknow anything about the big screw on the passenger side that's labeled lean? When the car runs it really smells like gas. I bet the mixture screws will help with that.

455man

That sounds like the choke. I'm not sure how to adjust it but I'll be watching the thread for others to chime in.

RetroRanger

what size carb is it or model number

oldsmobum

That is indeed the adjustment for the choke spring. It will adjust the point that the choke butterfly opens up. Adjustment in the direction of "lean" will make it open sooner. Will need to know more about the carb before adjustment procedures can be described.

cluelesscutlass

its a holley four barrel and the the numbers that count on it are 6497. I've tried pulling the two screws out till the idle goes down but with nothing happens. Its worth mentioning that the car has been sitting for a long long time.

oldsmobum

You do not turn the screws OUT until it slows, you turn them IN.

Remember, turn them out (counter clockwise) 3 full turns each, with engine off.
Turn engine on, then 1/4 turn IN (clockwise) each one at a time until engine idle drops

BosMobile

Hey man,I'ts going to be important to find your carbs model #,Usally found on the air horn,or top of carb.Considering it's got an airhorn.The "big black thing,with 3 screws,is the choke.Holley has a great DVD,called "carb instalation and tuning ".Really opened my eyes.I't like 20 bucks in summit catolog.Good read.You might even could download it.I did'nt have a computer at the time.Holley also has great tech line,call them.Good luck my friend ,feel free to ask more questions of me,later,BO