302 timing
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302 timing
I am installing a 302 in my old F-150 and was wondering what timing setting would be good. I have a 600 holley and vacuum distributor on this engine. ( it was originally a '90 EFI 302) Any suggestions?
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From: Virginia
Set it around 8 degrees, get it warmed up good, and then test drive it in high gear on a long hill, putting a load on the engine. If you hear any pinging, the timing is too far up, turn it back a couple of degrees and try it again. If you don't hear any pinging, then turn it up a little bit more, and try it again. Keep doing this till you hear pinging under load, and then turn it back till the pinging goes away. Having the timing advanced as much as possible, without pinging, will give the best power and fuel mileage.
After this is all done, turn it off and let it sit for 5 minutes, and then try to start it. If the starter struggles to turn the engine over, then set the timing back a little bit more till the starter turns the engine easily.
When you are out there on your own with a modified engine, this is the best way to set the timing.
After this is all done, turn it off and let it sit for 5 minutes, and then try to start it. If the starter struggles to turn the engine over, then set the timing back a little bit more till the starter turns the engine easily.
When you are out there on your own with a modified engine, this is the best way to set the timing.
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I can get the engine to run great at 10 degrees, but ,after a sort run, I shut it off and it does struggle to turn over. I can set the timing back and it still struggles. I even have moved it back to where the engine runs very poorly, it seems to start good there.
It starts great cold and cranks good when hot, if you just shut it off and restart, but if you wait a few minutes, it cranks real slow.
Could this be a carb issue, rather than timing? It seems like if I floor the accelerator, it cranks easier and starts immediately, like its flooded.
It starts great cold and cranks good when hot, if you just shut it off and restart, but if you wait a few minutes, it cranks real slow.
Could this be a carb issue, rather than timing? It seems like if I floor the accelerator, it cranks easier and starts immediately, like its flooded.
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From: Virginia
You are correct, you are flooding the engine, which kills the spark for a little bit and lets the engine turn over easier. What is the situation with your ignition system. Is this truck completely stock, or is the wiring modified? The reason I ask, is the stock duraspark II ignition module has a white wire beside the red wire coming out of the module. This white wire should be hooked up to the red/blue that goes to the starter solenoid on the fender. When the white wire gets voltage during cranking, it tells the module to retard the timing a set amount to make the engine easier to turn over. After it starts, the voltage drops from the white wire, and the timing reverts back to where you have set it. A very nice feature for a stock system. Some of the high end hot rod systems have this feature too.
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Yes, this ignition system is stock for an '86 351. I repaced the 351 with a 5.0 and had to change the distributor ( the 5.0 was an EFI engine). I replaced the dist. with a remanned '84 stock distributor. I thought I could use the 351 dist. Everything looked the same except it had a 5/16 hex oil pump shaft; the 5.0 had a 1/4 shaft.
It seems to me that everything should be ok, unless ford changed modules or something between 84 and 86. I will check the wiring , I sure appreciate the feedback!
It seems to me that everything should be ok, unless ford changed modules or something between 84 and 86. I will check the wiring , I sure appreciate the feedback!
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I checked the wiring and it all looks ok. Do you think the ignition module could be bad and not retarding the spark, as it should?
I also had the same problem ( hard starting when hot) with the tired old 351, but attributed the problems to the fact that the engine was in such bad shape. (I retained the same ignition module)
I sure wish I had a known ,good ignition module, that I could try!
I also had the same problem ( hard starting when hot) with the tired old 351, but attributed the problems to the fact that the engine was in such bad shape. (I retained the same ignition module)
I sure wish I had a known ,good ignition module, that I could try!
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From: Virginia
Make sure you have voltage on that white wire at the module when the engine is cranking. I have also heard rumors, but cannot verify, that some of the aftermarket modules did not have this feature. Do you have a motorcraft module?
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My voltmeter shows about 4.5 volts when cranking. The module appears to be an aftermarket module. I haven't removed it from the inner fender, but it does not say motorcraft on it (that I can easily see).. It seems to me like the Motorcraft modules said motorcraft, cast into the metal. Hmmmmm!
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From: Virginia
I have heard the best place to get a good original module is the junkyard. It doesn't have to be from a truck. Any Ford/Lincoln/Mercury with any type engine, so long as it's a duraspark II with the blue grommet where the wires come out.
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From: Virginia
I have heard the best place to get a good original module is the junkyard. It doesn't have to be from a truck. Any Ford/Lincoln/Mercury with any type engine, so long as it's a duraspark II with the blue grommet where the wires come out.
I would check the "s" terminal over that the starter solenoid, and see if it has 4.5 volts too. If it's higher, you might have a wiring problem from that wire to the white wire.
I would check the "s" terminal over that the starter solenoid, and see if it has 4.5 volts too. If it's higher, you might have a wiring problem from that wire to the white wire.
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The junkyards, in my area, are few and far between. Usually if I am lucky enough to find an original good part, it is about 75% of the cost of a new part.
I will have to check it out. I have found a place on the internet that claims they have a new genuine Ford ignition module for about $60. Not a real bad price, IF I knew that was the souce of my problem.
Again , I truly appreciate the time you have spent on my problem! Thanks!
I will have to check it out. I have found a place on the internet that claims they have a new genuine Ford ignition module for about $60. Not a real bad price, IF I knew that was the souce of my problem.
Again , I truly appreciate the time you have spent on my problem! Thanks!
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update - I bought a new Motorcraft module. Installed it, and have the same problem.
Could the coil be a problem, I am using the same coil that was on the old 351 motor and the 351 had the same starting problem.
Could the coil be a problem, I am using the same coil that was on the old 351 motor and the 351 had the same starting problem.