My 460 Build

Thewespaul

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I would almost guess it needs a lot of timing to make up for something, like masking an issue. Had that happen on a k5 blazer I built.
 

Dieselcrawler

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Did you degree the cam? Or just toss it in and set it straight up? I seen a few that set it straight up then checked it and found it 5 degrees off
 

FordGuy100

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I'm beginning to think the harmonic balancer has slipped, which I guess occurs. Cam was degreed. I also found the vacuum valve thing that sits on top of the thermostat housing is bad causing it go give the vacuum advance vacuum all the time, which it shouldn't. Which was causing my severe lack of power when lugged as I lost vacuum and thus timing. So right now timing is set to where it doesn't ping and runs good, I'll leave it there indefinitely. I'm getting the diesel itch already.


With timing straight up, and the cam plus porting, this thing has some pretty dang impressive power. Much stronger then my IDI.
 

FordGuy100

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Threw a cheapo muffler on it today. It sounds good if you like a kind of 80's mullet type of sound but I won't complain for a $40 setup with hangers and what not.
 

Dieselcrawler

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I actually tore my 460 apart today to start building it. I did find the balancer was coming apart. I could move it by hand on the rubber
 

raydav

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I have several 460s. The smog motors came with the cam retarded four degrees. There are timing sets that provide for plus or minus four and eight degrees. I have installed them all at plus eight. That is twelve degrees from stock. They all work very well.
 

FordGuy100

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I'm still getting popping out the exhaust when its up to temp, and engine has a slight shake. It did the same thing before the heads and cam. Spark plugs and wires are all new and every cylinder seems to contribute to engine running (ie unplugging wire causes more shake), plus all the plugs look the same and normal. I'm starting to wonder if its a carb tuning issue, so I was thinking about ditching the factory carb and getting a replacement ~600 cfm to go in its place.
 
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FordGuy100

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You know what, looking at pictures it appears I'm running lean. All spark plugs, which only have about 150 miles on them, are brownish grey. So I either have a vacuum leak of sorts or carb is out of tune (and is untuneable without knocking out those hardened tamper proof plugs.
 
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no mufflers

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it sounds like my 302 with a big cam. do you have a larger cam in it?

it would love a holly double pumper, 650 to 750 cfm.
 

Thewespaul

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I can feel my 80s mullet growing in! Sounds good imo but with your setup probably not what yours is supposed to sound like. Do you have a vacuum gauge and if so what are your readings? Modern gass reaks havoc on carbs, new carb or a rebuild could help, you may have a bunch of crud in your carb if it sat around for awhile while you rebuilt the engine.
 

FordGuy100

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Carb was rebuilt by myself but that doesn't mean I didn't screw something up.

The cam is the summit k3500 which is a very mild cam, maybe they put the wrong one in the box

It sounds cool but it just doesn't seem right.
 

FordGuy100

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So it's got to be carb related. Cold with choke on it runs perfect and a smooth idle. Warmed up the idle gets choppy. You can now hear it popping on decel, and when it warmed there is a lag in power when you first hit the throttle. Gotta be running lean.
 

IDIBRONCO

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I'd agree with the lean condition. Runs smooth with choke closed, rough with choke open is a pretty good sign. At least with dirt bikes and atvs, popping in the exhaust during deceleration is another sign of running lean.
 

FordGuy100

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Was about to buy a carb when I said screw it I'll drill out those hardened plugs and see if I can't adjust idle mixture.

Thing is running smooth as silk. Took 2 extra turns on each to get it to smooth out (from a factory setting of 2 turns off bottom).

Now I'll retime it in case it doesn't need as much base timing.
 

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