Odd Problem

[73SWING]

Edelbrock carbs will generously flood with fuel under as little as 7.1 pounds of pressure. This would cause the car to idle poorly, especially under load and will smooth out and behave once RPMs are higher and the bowls are not allowed a chance to fill up...

Simple test:

start the vehicle and run until the issue appears then apply pressure to the fuel inlet hose with a pair of pliers. If the condition improves you more than likely found your culprit.

Kind of a shot in the dark, but i hope it helps

 

[MOPARJ]

Edelbrock carbs will generously flood with fuel under as little as 7.1 pounds of pressure. This would cause the car to idle poorly, especially under load and will smooth out and behave once RPMs are higher and the bowls are not allowed a chance to fill up...

Simple test:

start the vehicle and run until the issue appears then apply pressure to the fuel inlet hose with a pair of pliers. If the condition improves you more than likely found your culprit.

Kind of a shot in the dark, but i hope it helps

I have a Holley I can swap as well, but I am having a hard time understanding how the carb (even the new carb) can be flooding all of the sudden after so long. I even put a new pump on last week. Fuel pressure is still 7-8 psi at times, according to the autometer gauge.

 

[fstfish66]

get a vacuum gauge, see what it tells you,,,i highly doubt the fuel pressure is your problem,,since you have changed carbs,, what about the gasket under the carb??? reused??? have you held a timing light on the motor at idle just to see if its stable??? all these suggestions area long shot good luck

 

[rod440]

Is there a ground strap or cable from the engine to the firewall/chassis? Just one more thing to check.Good luck!

 

[MOPARJ]

get a vacuum gauge, see what it tells you,,,i highly doubt the fuel pressure is your problem,,since you have changed carbs,, what about the gasket under the carb??? reused??? have you held a timing light on the motor at idle just to see if its stable??? all these suggestions area long shot good luck

Vacuum is about 8-10 at 550 rpm, steady and roughly 12-13 at 900 rpm. It does go up with revs as should.

Timing is ok. Pulls up through the rev range without any misfires.

There is a ground strap from the head to firewall (cleaned), head to battery, and one to the chassis as well.

I do have quite a bit of timing in it, but no audiable detonation. About 18-19 degrees of initial. I have always had this much timing in it. The difference is now that when I retard the timing a bit, there is a bigger difference that if I would of previously.

 

[cuda2ya]

If I read right you mentioned a gurgling sound. Hand touch the gas line close to the carb . If the line is hot your gas is vaporizing and not completly filling the chambers Check where your lines are run and how hot is the engine. You should not hear that sound unless there is not enough fuel in the carb and engine is hot. This is a strange situation but had happened to me and was my fuel line was hot (too close to engine and engine running on the hotter side) causing fuel to vaposize before it got to carb (not ness vapor lock but close). maybe that will help

 

[dusty1]

Thought that would get your attention. I bought a Wedge that I am looking for a surge too. Mine has goes up and down as it builds speed, and my foot stays steady at one spot on the accellerator. An article I read said to check for an intake leak with a hose and propane. Motor changes sound, and you found your leak. Havent tried it yet but better than wd40 all over the motor.

 

[MOPARJ]

Update:

I have been driving the car here and there recently, to figure this out.

A few nights ago, I was sitting in the drive through at an In-N-Out with the car idling in drive at the low 550 rpm that it has been idling at lately. Suddenly, the revs came up to about 700 rpm and it smoothed out. On instinct, I put the car in neutral and the revs rose about 150 rpm, which is normal.

When I drove away, it didnt fall on its face when shifting from first to second and is running decent.

This new trend had continued for the past few days.

What the hell??! It now seems like it was/is the converter, but I am trying to determine what about it is/was causing the issue for a couple of weeks. Maybe there was an obstuction somewhere?