So on my 84 z28 when ever i brake hard or make a sharp corner my rpm's shoot way low and it seems as if the engine is about do die...I wonder if any of you guys have experienced that....im guessing that the gas sloshes in the tank and it looses pressure but I have over half a tank of gas, and whether I have a full tank or not it always happens.......

 

could be float level set too low-uncovering the jets during the braking or cornering.

 

Or too high... not sure what kind of carb we're talking about here, though.

 

Sounds like a vacuum leak to me. Maybe your brake booster is giving out.

 

I actually do believe that my booster is giving out but i dont see why my rps should fall like that..

 

Brake boosters work off vacuum. When they go bad they leak creating a huge vacuum leak thus causing your RPM fluctuation.

 

well is there a way to know forsure that I have a bad brake booster.....?

 

If the booster is bad you will have a stiff pedal, and/or hte engine will run badly with the pedal pushed down. When you push in the pedal you're increasing the volume of the vacuum... system. The total volume of all your vacuum lines and intake manifold etc is static, but when you hit hte booster, you place a demand on that system to pull out all the atmospheric pressure in the brake booster. So it will regardless cause a small vacuum dip on a gauge. How much varies, and Im sure there's a point where it's too much and something is wrong.

It's just a judgment call really unless you have a vacuum gauge hooked up while you hit the pedal. But remember if something else is causing the engine to sputter and nearly stall, the vacuum will be low anyway. Correlation isnt causation.

 

well i do have somewhat of a stiff pedal.....but the engine runs fine with the pedal pushed down.....

 

try to push hte pedal in with the car off. You will probably get 1 to 1.5 full pumps out of it (there's a check valve in there...) and after that it will be stiff as a rock. You're looking for something between those two extremes.

Stiff pedal is good, but theres a difference between a stiff pedal and booster thats not working well. Again, kind of a judgment call.

 

hmmm....ye you got a point...well ima look into it...I appreciate the help...