Can not get pass 45 mph

Did it run ok in the past? Has something been changed? Are you saying it just tops out at 45, or does it kinda sputter or hesitate?
 
To Monitor a dwell meter while driving I clip the lead to the point side on the coil terminal and duct tape the meter to the windshield, of coarse the hood is off. Where I was going with this, I too had similar symptoms, it turned out to be a flaky ignition cable.

On a different car, something that caused a strange behavior was the engine didn't have a good ground. A temporary ground strap confirmed the problem.

Just stuff to look for...
 
w.michael said:
Many years ago, when good quality replacement points were difficult to find, I had this problem because the spring action on the points was too weak. It would run at slow speeds, but as the rpm's increased, the point spring did not close the points fast enough, and the engine would lose power and start to run roughly. Just check the points by pulling them open with your fingernail and see if it "feels" right.

W. Michael
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I remember when Chief had NEW points in hand, he would "feel" the spring pressure & "tweek" them, if necessary.
Bill W.
 
How much spark advance are you running?

My 30 roadster would start to act it like it was missing when it got up to 45-50 mph. I was running the the spark lever at the bottom - fully open. One day on a tour I moved the spark lever up slightly to 1/2 to 3/4 open and the engine smoothed right out and ran better. Top speed also improved.
 
I was also going to suggest checking the points spring tension. If the tension spring is rusty or got bent it will let the points bounce or float at higher speeds. When I was in high school it happened to my 55 Chevy when 12 volts got sent through the points. It took the temper out of the spring and the points would float at 35 MPH.
 
I had a case once where the car seemed to run normally, that is hitting on all cylinders, starting and idling pretty normal but just seemed to top out at about 25-30 MPH. My first check on an unknown car is to check compression. If I don't find 4 cylinders puffing along at 50 or more PSI, I can stop there before wasting time on tune-ups. While I have the plugs out checking compression, I can check the plug gap and condition. Plugs looked new(people always foodle with their car before bringing it to me.) BUT, the plugs were gapped at 25 thous! I gapped at 35, made no other changes and the car then ran normally! Go figure. Rainmaker Ron
 
Hey guys, I am going through a similar problem. Just did a trip about 50 minutes each way (longer back home). On the way there I was driving 57mph steadily and the car ran fine.

On the way home, the car seemed to stop responding after hitting the high 40s .. the added gas pedal after that sppedometer did not help it accelerate. Anyone have an idea of what I should check?

Ps - I have an exhaust leak that seems to have gotten worse during the trip
 
Bob Johnson said:
I was helping a club member tune up his car. I took it for a test drive and at about 45 mph (broken speedometer so just a guess) the car would loose power. If I backed off the accelerator the car would have power again. It also happens in second gear at about the same rpms. I adjusted the timing and points, checked the fuel flow at the carburetor (good). Took apart the carburetor, blew out the jets and took out one red washer (there were 2) on the float bowl jet. Checked the filter in the carburetor (OK). Adjusted the ferrule at the carburetor end of the fuel line. Still had the problem. Any suggestions.

Bob
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what should be the max speed be on a level road?
 
Bob Johnson said:
I was helping a club member tune up his car. I took it for a test drive and at about 45 mph (broken speedometer so just a guess) the car would loose power. If I backed off the accelerator the car would have power again. It also happens in second gear at about the same rpms. I adjusted the timing and points, checked the fuel flow at the carburetor (good). Took apart the carburetor, blew out the jets and took out one red washer (there were 2) on the float bowl jet. Checked the filter in the carburetor (OK). Adjusted the ferrule at the carburetor end of the fuel line. Still had the problem. Any suggestions.

Bob
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Spark plugs breaking down under load?
Bill
 
FrankWest said:
what should be the max speed be on a level road?
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Ford advertised that they could go 60 MPH, but that doesn't mean it's a good thing to do.

I'll bet my Olds can do over 100, but it wouldn't last long if I maintained that speed, and it has a counterweighted crank, oil filter, and pressure oiling.
 
30FordA50 said:
Hey guys, I am going through a similar problem. Just did a trip about 50 minutes each way (longer back home). On the way there I was driving 57mph steadily and the car ran fine.

On the way home, the car seemed to stop responding after hitting the high 40s .. the added gas pedal after that sppedometer did not help it accelerate. Anyone have an idea of what I should check?

Ps - I have an exhaust leak that seems to have gotten worse during the trip
Click to expand...

if its an exhuast manifold leak maybe the intake is leaking also causing you troubles. how is it idling?
 
I would like to build a little on what w.michael said. He alluded to "points float." Essentially, the distributor cam is spinning so fast that the points can't close quickly enough. This can be caused by a weak points spring. In my case, I had a broken points spring. A thin copper conductor was all that was forcing the points closed. It was fine at idle, but when I got up to speed, it would just sputter and barely run. I drove home 100 miles that day... very frustrating.

Good luck,

Ken
 
Hello all, thanks for the suggestions. The exhaust leak is between the manifold and tailpipe connection. I am having a hard time keeping them bolted together. The bottom connection keeps loosening up on me. There is no rough idle but there is a faint sound of a misfiring if the makes any sense.
 
Someone a while back mentioned they had an exhaust leak in that same location and the exhaust entering the carb made the car run very poorly.

Be sure the long side of the clamp is down, and also make sure the pipe has a good flange. Most of the budget pipes need to have the flange made better and the 90* bend removed slightly.
 
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