problem off the line

[73redblaze]

so my bro-in-law has a 69 firebird that we have been working on for a little while now. when we mash on the gas petal it stalls for a sec then takes off? its like it gets flooded or somthing. i know you guys will know exactly what to do but im a noob to this game so if you could, fill me in plez?

 

[Burbdood 74]

The only things I can think of is either the float level is low, accelerator pump is shot on the carb or the vacuum advance on the distributor is sticking. What kind of carb does it have on it anyway and does it have electronic ignition or points style distributor?

 

[4X4HIGH]

What carb is on it? If it's a Holley i can tell you how to PROPERLY adjust the accelerator pump and your hesitation should go away. I have yet to see anyone who knows hot to set it properly.

 

[73redblaze]

it's a holly 700 and it's a points dist

 

[Burbdood 74]

Well, new points, (or even an electronic ignition conversion) might help burn the fuel a little more effeciently. But since the carb is a Holley 700, it might be a little too much for the engine.

What engine does it have?

 

[AZ79K5Project]

Check the timing and vacuum advance. Start with the simple stuff first.

 

[Slapperbar]

I think 4X4HIGH hit it on the head. I sounds like the pump shot isn't right.

 

[4X4HIGH]

it's a holly 700 and it's a points dist

The proper way to adjust the accelerator pump is to have someone help you hold the throttle wide open, while you also depress the accelerator lever until it won't move any further (i use a small screw driver under the float bowl as a leverage point and then pry downward on the lever), now you need to adjust the screw/spring so there is only a .015" gap between the pump lever and the adjuster screw.

Most people only hold the throttle wide open and then do the adjustment but then the adjustment is WAAAAY to loose. I don't know how many peoples cars/trucks i've cured their off idle lag problem by adjusting the accelerator pump properly.

Also installing an HEI distributor is a big help in eliminating the burnt point syndrome that is common for a points distributor.

 

[mrk5]

I agree with 4x4High. Your BIL has a lean-stall issue. If you still have the issue after adjusting the accelerator pump as 4x4High described, you may need to try changing out the accel pump cam and discharge nozzles.

There's a lot of good carb tuning info over on thirdgen.org; actually that crew would be right up your BIL's alley with is 69 Firebird. I love that body style BTW.

 

[73redblaze]

thanks for all the help guys. i will give it a shot.