coupple quick 460 questions
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coupple quick 460 questions
i have a 460 sitting in my garage for my 86 F-150, i was debateing on building it but dont have the money so i decided on a cam/timeing set swap, and intake swap. im fairly new to 460s so i got a coupple simple questions. this is an 86 engine im pretty set on the weiand stealth intake but dont know where to go on the cam i was thinking the crane 353901 but i dont know the stock compression and i have a holley 4150 700cfm dp ms 4 corner idle to throw on top of it and im probably going to put the HP main body on that. would that make a fairly decent engine for hauling fire wood and messing around off road?
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From: Edmonton, Alberta Canada
the compression on the mid 80's 460's was pretty bad at about 8:1 maybe as high as 8.5:1. for waht you want to do, keep the cam small. something in the 240 - 260 duration will be a good torque cam. with the stock heads, that is about all you need. find a cam that has a higher exhaust duration as that is where the 460's need the most help.keep lift at max .5 if keeping the stock heads. that is all the stock valves and rockers can handle.the Weiand Stealth is a real decent intake. probably one of the best dual planes out there for the 460. good rpm range from around idle to about 5500rpm. i wouldn't use a double pumper, more of a race carb then a street carb. find a 650 - 750cfm vacuum secondary carb. much better choice then the double pumpers. even the stock 600cfm Holley would be a better choice on the street. compression was pretty bad on these motors, so no need in going hog wild as you are limited on how much you can get out of these motors without changing pistons and doing some head work to get the power potential out of them.rgdsMike
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what you described is pretty much what the 353901 is
Cam Timing: TAPPET @.005
Opens Closes ADV Duration
Intake 17.0 BTDC 59.0 ABDC 256.0 °
Exhaust 67.0 BBDC 21.0 ATDC 268.0 °
Lift: Intake @Cam 2847 @Valve 487
Exhaust @ Cam 3027 @Valve 518
Cam Timing: TAPPET @.005
Opens Closes ADV Duration
Intake 17.0 BTDC 59.0 ABDC 256.0 °
Exhaust 67.0 BBDC 21.0 ATDC 268.0 °
Lift: Intake @Cam 2847 @Valve 487
Exhaust @ Cam 3027 @Valve 518
Elder User
Joined: Jun 2004
Posts: 800
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From: Edmonton, Alberta Canada
that looks like a decent cam. should wake up the 460 quite a bit.
just make sure to use the early timing gear set when installing the cam or a good aftermarket one and install the cam straight up. the late gear sets (72 and newer) were 4 deg retarded (i think) and even going to the early (71 or older) gear set in the stock 460's really improve power.
have fun with it
Rgds
Mike
just make sure to use the early timing gear set when installing the cam or a good aftermarket one and install the cam straight up. the late gear sets (72 and newer) were 4 deg retarded (i think) and even going to the early (71 or older) gear set in the stock 460's really improve power.
have fun with it
Rgds
Mike
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From: Edmonton, Alberta Canada
it is probably at the upper limit.
you will have to do a mock up assembly and check the rocker arm geometry. you will want to check that the tip of the rocker arm is not too far to either edge at zero lift and max lift and that the rocker sweeps through the valve tip properly. also will have to check that the rocker arm doesn't hit either the valve retainer or any othr part of the head or bolts at full lift. because these heads use non-adjustable rocker arms, you might have to either convert to adjustable rocker arms (i think either crane or comp cams makes a pretty inexpensive kit for this) or use different lenght pushrods to get the correct geometry for this cam. depends on the core they ground the cam on and how close it is to the factory core dimensions.
as long as you are not planning on revving over 5k for extended periods, the stock springs should hold out long enough. they probably aren't up to the task of extended high rpm though.
as with any upgrades, you will have to assemble and check for fitment.
good luck
Rgds
Mike
you will have to do a mock up assembly and check the rocker arm geometry. you will want to check that the tip of the rocker arm is not too far to either edge at zero lift and max lift and that the rocker sweeps through the valve tip properly. also will have to check that the rocker arm doesn't hit either the valve retainer or any othr part of the head or bolts at full lift. because these heads use non-adjustable rocker arms, you might have to either convert to adjustable rocker arms (i think either crane or comp cams makes a pretty inexpensive kit for this) or use different lenght pushrods to get the correct geometry for this cam. depends on the core they ground the cam on and how close it is to the factory core dimensions.
as long as you are not planning on revving over 5k for extended periods, the stock springs should hold out long enough. they probably aren't up to the task of extended high rpm though.
as with any upgrades, you will have to assemble and check for fitment.
good luck
Rgds
Mike
