holley 4160 dies on acceleration

[Jase.Heuer]

i have a holley 4160 600 CFM on a 302 that is dying on acceleration. i currently have 63 jets and a 31 squirter. does anyone have a suggestion for what size to use?

 

[rocket366]

your engine issue is tough to diagnose on a forum for sure.

Changing jets or nozzles is a tuning thing for a engine that runs without issues.

I would say that if the accelerator pump or pumps are squirting fuel working the throttle

and the engine is dying than I would look at weak spark or some other cause.

Note that a mechanical secondary carb with no secondary pump action will be an issue

and you can feel that.

Paul

 

[72HCODE]

you did not provide much information

1) is there a difference when the engine is cold verse warmed up?

2) is it dying if you slowly accelerate? or this only happens when you stomp on it going to wide open throttle.

3) is the car backfiring through the carb then dying?

4) is the car backfiring through the tail pipe?

5) is this a new problem was the car running fine something changed and now its dying?

6) is your accelerator pump linkage setup properly?

there are many more questions that will help narrow things down

 

[Jase.Heuer]

you did not provide much information

1) is there a difference when the engine is cold verse warmed up?

2) is it dying if you slowly accelerate? or this only happens when you stomp on it going to wide open throttle.

3) is the car backfiring through the carb then dying?

4) is the car backfiring through the tail pipe?

5) is this a new problem was the car running fine something changed and now its dying?

6) is your accelerator pump linkage setup properly?

there are many more questions that will help narrow things down

1) is there a difference when the engine is cold verse warmed up?

The issue is worse when the car is cold

2) is it dying if you slowly accelerate? or this only happens when you stomp on it going to wide open throttle.

It happens whenever the accelerator is pressed

3) is the car backfiring through the carb then dying?

No the car is not backfiring

4) is the car backfiring through the tail pipe?

Same as above no backfiring

5) is this a new problem was the car running fine something changed and now its dying?

Just putting the car together after someone else had it built

6) is your accelerator pump linkage setup properly?

According to the instructions and the gauge measurements yes

 

[Don C]

Is the carburetor new, if not was it rebuilt? A used carburetor that was allowed to have fuel dry out in it will likely have plugged passages. However, a lean condition on acceleration will usually cause backfiring through the carburetor.

I would check the ignition timing, dwell, and spark output.

 

[mjlan]

It sounds a bit like timing to me. What's yours set at?

Even if you pump shot is wrong, slowly opening the throttle should get allow the carb to transition circuits if there isn't anything plugged up or wrong with the carb. Is your power valve ok and it's opening point ok?

 

[72HCODE]

Jetting is mostly used at cruise so changing them isn't going to have an effect on the engine dying when touching the accelerator.

Shooters will have an effect. Accelerator pump CC size, accelerator cam power valve will have an effect.

however just touching the throttle killing the motor, usually indicates another problem.

---

if you idle the motor with the trans in park or natural, does the engine die when touching the throttle?

shutdown the motor, look down the carb throat, and move the throttle by hand do the shooters spray evenly down into the carb throat the second the linkage on the throttle moves?

Cap off the distributor vacuum advance at the carb, does it still die off idle?

you could have:

possible clogged fuel circuit in carburetor.

possible vacuum leak.

ignition problem.

electronic or points ignition?

using a Vacuum gauge what are you making at idle?

 

[71 gbvert]

+1 on the suggestions already given, however don't forget to check the fuel pressure. And if you haven't already, you may want to check the fuel filter.

 

[will e]

I assume you have checked the float levels.

 

[Jase.Heuer]

Ok so I checked the float level and rebuilt the carb. I am pretty sure that I found the issue. The old fuel filter that was on the fuel mine was hollowed out... So I put a new fuel filter on and had the carb cleaned out and amazingly it's running better. Yay for idiots that do crazy crap to their cars then sell them. So new fuel filter is a glass see through and well it's nasty so I put an extra inline before the fuel pump to try to help.

 

[Bill73Ragtop]

IMO: Get rid of the glass inline. They have a tendency to leak gas onto the manifold and cause very nasty fires...

Sounds like you have a lot of sediment and other stuff floating around the gas tank. Consider draining and flushing it.

Looks like you are on the right track.