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Discussion Starter #1
I took my car out this weekend to put some miles on the recent rebuild, and I wanted to rev it up to about 5500. However, the engine started dropping out at 5100 RPM. It almost seemed like the rev limiter was kickin in, but I verified that it was set at 6000. Thinking it might only happen under heavy acceleration, I gradually tried approaching 5100 but it still began dropping out.

I didn't have time to start looking in detail for the problem, but I wanted to get some ideas about what is the most likely cause.

It is currently using the stock distributor until I can get the magnetic triggering worked out with my new distributor. Could it be the points floating? Or maybe too much/too little advance?

I'm also using the stock fuel pump. Could it be a fuel starvation problem?

I have not yet jetted the carb (Edelbrock 600), but I'm not sure this would cause it.

I recently adjusted the Rhoads lifters to 1/4-turn of preload, so I don't think it's valve float or lifter pump-up.

Any ideas on the best place to start or how to isolate it?

Thanks!
 

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I installed a 600cfm Ebrock carb on my 302 and it was very lean....I went 1 stage rich on cruise mode and 2 stages richer on power mode....main jet .104 metering rod (.075x.047) secondary metering .101...Russ..
 

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Discussion Starter #5
I'm running at 4600 feet of elevation and the Edelbrock 1405 is supposed to be jetted for performance (i.e. closer to 13:1 A/F ratio). With the elevation and stock jetting, I'm probably running rich. I plan to get to the jetting once nicer weather settles in.

What are the chances of seeing valve float with new, dual valve springs and 1/4-turn of preload on Rhoads lifters? Is there a way to tell for sure?

I can play with the initial timing some, but I can't do much with the advance curve until I get my other distributor in and funcitonal.

Are there any suggestions for how to identify which problem is occuring? Or do I just correct each one until the problem goes away?
 

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I'd sure suspect the stock distributor. An old trick that might help you figure it out is to take a short piece of vacuum hose and put it behind the point arm to act as a second spring in case the points are bouncing. If it makes any difference then you know it's a distributor problem. You might also want to try disconnecting the tach in case there is a problem with it.
What did you set the initial timing at? If it's at least close to where it should be I dont think that's your problem.
 

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Darren...couple of quick Q's. How long was the car down during this rebuild. Looking at you 66 and the specs, how much of this is still current. When you were pedal down @ 5100, when you let off the gas, did it smooth out? Did it back fire at all?
 

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sounds like valve float to me too --- if dual springs look for a broken inner --- may be plugs or something also but have to start somewhere -- did it do this before any chages were done? if so look in that direction
 

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Discussion Starter #9
The initial timing is at 12 degrees without the vacuum advance connected. It advances to about 30 - 32 degrees max at higher RPM. I know this is not ideal, but could this be the cause because it is not advanced enough? I'll try the trick with the vacuum hose to see if it makes a difference.

The car was down for about a year during the rebuild, with the engine being rebuilt last winter and started up this past spring. Due to lack of time and trying to resolve some other issues, it only saw about 75 miles of use this past summer. All of the specs listed in the YOURCARS sections is current.

When I let off at 5100, it didn't smooth out until it dropped below 5100. At 5000, it seemed as smooth as any other lower RPM. There was no backfiring at all, it just felt like the rev limiter kicked in.

To eliminate the rev limiter as a cause, I'll dial it down to 4000 and make sure it limits properly there. Then I'll set it to 7000 to make sure it won't even be close.

I looked at the springs and pushrod guides a few weeks ago when I adjusted the lifter preload. Originally I was running 3/4 of a turn and decided to back it down to 1/4 turn based on other info I saw posted in this forum.
 

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Had similar problem with 351C. Checked all the normal stuff. Solution was new plugs, a wide top dist. cap and 9mm wires. Now she rev's to 5800. Before she would stop about 5000.
 

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Points suck. No doubt about it, even a Duraspark will beat the tightest points system in the world. I made the switch 2 years ago and will NEVER go back to points.

Remember when changing, Ford likes to make many different shaft diameters. Be careful.
 
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