[RattVette]

Having an issue with my car heres a brief description of whats going on , im having an issue with loss of power under acceleration, if I give it gas it wants to fall on its face or runs like it is just flat, with no power

Nothing has been changed on the motor, and symptoms have just showed up today. at first I thought it might be a missfiring plug so I pulled and replaced the plugs (NGK-R's), wires are new(accel) as is the distributer and coil (accell billet vacuum advance unit)

engine is a 350 .030 over (fresh build) with .477 lift cam hydrolic lifter, flat tops with 64cc heads, carb is an edelbrock 1406, performer intake,fuel pump is a mechanical edelbrock unit

So heres my thoughts and input is greatly appreciated, Im thinking I may have a fuel delivery problem.

Could the pump be bad and causing this, also could it be the accelerator pump in the carb or possibly a clogged fuel filter, would something like that cause the above symptoms

Or does it sound like something is amiss with my distributer

Im kinda stuck here, this is my first performance build and its ran quite well all summer and Im stumped (also not sure on fuel pressure as I dont have an inline guage, but will be adding one in the morning as I now see a need for one)

So all this said any ideas on what to check as I really dont want to just throw parts at it until it works again

All help welcome:cheers:

 

[Brass Pass]

I would try a new fuel filter.

 

[bloodmanic]

i would try a filter.

 

[Fred Mann]

Look in the tank and check if the filter bag is deteriotating. Is there a filter built into the carb inlet (or inlets)? You might need to change that, as well as the in-line filter mentioned by the guys above.

Sounds like a fuel problem, but you might put a timing light on the engine and see if the timing advances with increasing rpm, up to about 3000rpm. Maybe there's a problem with the mechanical advance.

What's the engine doing, does it stumble and then pick up speed normally? Or does the engine not accelerate at all?

 

[BonneRisque]

Make sure none of your spark plug wires are arcing

Look for vacuum leaks

 

[RattVette]

Ok added a fuel pressure gauge 4 1/2 to 5 pounds of pressure

new fuel filter

no vacuum leaks (checked it with carb cleaner)

Engine runs fine till she comes up to operating temp and then it wants to fall on its face under acceleration

Kinda feels like alot of cylinders arent firing and then do

Could it be internally in the distributer

or possibly a sticky lifter

 

[RattVette]

Look in the tank and check if the filter bag is deteriotating. Is there a filter built into the carb inlet (or inlets)? You might need to change that, as well as the in-line filter mentioned by the guys above.

Sounds like a fuel problem, but you might put a timing light on the engine and see if the timing advances with increasing rpm, up to about 3000rpm. Maybe there's a problem with the mechanical advance.

What's the engine doing, does it stumble and then pick up speed normally? Or does the engine not accelerate at all?

its not wanting to accelerate like it has no power, the and when it does the tourque just isnt there like it was, car could break the tires lose at a 25 mph roll and now just seems limp like it has no power, the accelration seems real flat and stumbles

 

[bunyz06rabit]

Power valve in the carb. Rebuild kit. JMHO...

 

[Bowtiedblood]

Per Edelbrock's website 5.5psi is optimal on a 1406, however the 1406 is shipped factory set to run lean. Maybe you need to recalibrate yours for more fuel since you have freshened your engine up a little.

 

[Fred Mann]

Power valve in the carb. Rebuild kit. JMHO...

In a Holley, the power valve is a mixture enrichment device for near WOT and WOT. Does the power valve have the same function on the OP's carb? I'm not familiar with the Edelbrocks.

From the description, I feel like the trouble is starting before the power valve would have an effect, if it behaves the same as in a Holley.

 

[TimAT]

Accelerator pump. Sounds like it's either a late or weak pump shot.

 

[RattVette]

Rebuilt the carb, found the accelerator pump rubber was cracked and the carb was missing the little ball bearing ???? but after cleaning it and re assembling it and a little fine tuning and a valve adjustment the car is running better then it ever has.

thanks everyone for all the help:thumbsup::cheers:

 

[Fred Mann]

Rebuilt the carb, found the accelerator pump rubber was cracked and the carb was missing the little ball bearing ???? but after cleaning it and re assembling it and a little fine tuning and a valve adjustment the car is running better then it ever has.

thanks everyone for all the help:thumbsup::cheers:

Nice call TimAT!

RattVette, this is what I was getting at when I asked if the engine was stumbling and then would start to accellerate. The accelerator pump is there for sudden large throttle position changes. If you slowly step on the gas, the carb's metering system can keep up with the airflow change. I like to play Sherlock Holmes on these engine problems, but didn't get the picture on this one. So far I'm 0 for 900. LOL.

Glad it's figured out.