Drove the 1974 Corvette to work yesterday, and for the most part it is running great. I did notice though, that when I make a left turn, like at an intersection, the car feels like it runs out of gas then runs fine when it gets straightened out. This happened twice yesterday, both times I was moving out at a pretty good clip, but not pulling any huge G's or anything.

I had thought maybe the pickup in the fuel tank was getting uncovered, but the loss of power is instantaneous when I crank into the turn, and I don't think fuel is flowing that fast. I have a new fuel pump, filter and lines, so now I think it must be an adjustment in the Edelbrock 1406 carb. Anybody have any ideas?

I am leaving town for the weekend, so I will look into it further on Monday if I am back.

Thanks a million!
John

 

Could be that the float bowl level is to low and needs to be adjusted.

 

Could be something as stupid as a motor mount. I've had it happen before....

 

I am trying to figure out what a left hand turn could induce that would cause stalling or loss of power..... does it do it with right hand turns? Does it do it with the directional on and or off?

I would think if the float bowls were low a hard acceleration going straight would show the same problem. (Dont know what carb you are running).

A bad motor mount should show torque rock no matter which way you turn but I guess could be more pronounced in one direction causing some type of electrical connection to be pulled but I would still expect this in a ***** out straight on acceleration as well. Or you could see it by opening the hood and power breaking the engine with one foot on the gas and the other on the break to see if the engine is really rocking.

Hook up your timing light to a spark plug wire and bring it into the car with you and hook it to the battery and then have someone watch how smooth the light pulses as you make these turns and the engine falters... if its sporadically lighting then you have ignition troubles.

If your tank pickup is off the bottom of the tank then I could see a right hand turn uncovering it but I dont think you would lose the engine that fast as the bowls would have gas in them as well as the lines unless you were doing donuts or a really long turn.

Is the car a stick or automatic.... is this power loss like the engine is revving like the trans is slipping and then ok way you straighten up.. if so could be low tranny fluid and your pump is cavitating in turns but man that would be low for that to happen.

 

You raise some interesting points, some of which will require further investigation when I can devote a little time to it.

It is interesting that the off-ramp just preceeding the left hand turn at the intersection is a fairly high speed right sweeper and I had no issues there. As I cross the lanes and get into the left hand turn lane all is well, but then it falls flat on its face when I turn left and it sort of coasts through the intersection, but picks back up about the time the turn is completed. When I have a chance, hopefully Monday, I am going to find someplace that I can just drive in circles to see if I can recreate the issue at will. It feels like a fuel starvation problem, but I suppose it could be ignition as well. It just feels like somebody shuts off the motor for a second. Disconcerting, but it comes back on so quickly that it makes you ask yourself, "Did that just happen?"

I have an Edelbrock carb on a L48 automatic. It is not the transmission...no motor revving, just no motor. I thought about the tank pickup, but don't think it have fuel starvation in one second.

I will let you know when I drive in circles and let you know what I find...it is always something, huh?

John

 

Sounding more like floats in the carb or possibly the accelerator pump is going. I dont know how the circuits run in them but the accelerator pump is in the front drivers side on most carbs and making a left could cause you to loose the fuel level there and not have the ACC to give you a sufficient squirt to transition from idle to power. Or the float level is just not enough and on left turns you simply cant get enough fuel for the ACC pump to squirt.

Maybe you can pull the carb apart and check the float level and replace the accelerator pump while in there. Don't want to spend you money but once your in there adjusting or at least checking the floats the accelerator pump is right there.

Call Edelbrock then can tell you how and what to do... they are very good that way.

Did a little looking on the web... seems this is an issue with some of these carbs they have an off road needle and seat kit that may help... discuss with the edlebrock guys I bet they have heard of it. Sounds like if double foot "1 foot brake1 foot gas" and keep the idle up it wont do it... see if that happens for you.

 

Before I even clicked on this thread, In said to myself "Hmmm, I wonder if he has an Edelbrock carb?" They have a reputation for doing exactly what you have described, and, from what I have read, (I have zero experience with Edelbrock carbs, myself) it's a float level problem. Not too hard to fix, you should be able to very easily find more info about it by doing a search.

Scott

 

Same issues here, also Edelbrock carb (1411). Left or right sharp turn without using the throttle = stumble.

Here's an interesting youtube video on how to set the float level. Haven't tried it myself yet, but seems doable.

https://www.youtube.com/watch?v=s-ab...tailpage#t=124