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Discussion Starter #1
Looking for some help here as im new to the 460 world. I recently bought a 76' f-150 with the 460 and a c6 tranny. Had it for about 3 days and when i was driving a knock started from under the valve cover. This happened after i put my foot into it to make it downshift up a very, very mild hill RPM was roughly 2800 and a loud bang came from the engine bay. Took the truck back to the house (1km away) and started to do the diagnosis on it. Left it for a couple of days and then finally took the time and tore the valve cover off on the driver side. One pushrod was completely missing the other was bent all to F and was able to fish it out without taking the rocker off. Once i saw this i tore the intake off, found the "missing" pushrod and noticed a bunch of other pushrods were bent. In total 3 pushrods were broke in half, and of the 16 only 6 appear to not have a bend in them; most were a mild bend.

Truck as purchased, (accord to seller)
Has Weiend Stealth intake--Confirmed
Slayer Quick fuel 600 CFM Carb-- Confirmed
Straight up Timing-- Not Confirmed
Crower Power Beast Cam-- Not Confirmed
Original 76' 460

Cam lobes appear to be in perfect condition, all of the lifters looked brand new with no visible wear. The seller supposedly did all the work to this truck 2 years ago and had used it as an occasional driver. So assuming thats correct something must have failed that im not thinking of?

My question(s) are
1. With his cam choice would stock rods have worked? I also think its too much cam for what he has in here but again, im new into this world.
2. With this bad of a failure i dont want to just replace the rods/rockers, something happened and it is NOT an over rev since i have had it, i drove this truck like a grandma. so somthing else must have happened and i need to find that problem first, could the timing have skipped ?
3. Long term goals for this truck was a complete tear down and throw a scat stroker rotating assembly in, Goals were high HP on pump gas. Im saying this because any replacement part on the top end im willing to upgrade if it would help in the future.

And lastly for my job i get free fuel, (regular) so any changes or upgrades for the time being would need to keep me in the 87 octane range.

Anyone else heard of this? Any thoughts?
 

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BBF's bend push rods for several reasons.

Spring retainer to seal contact when a higher lift cam is installed on an OEM head with out topping the guides and changing to P/C seals.

Spring stack when a higher lift cam is used with oem springs

OEM style push rods used with performance springs with higher open pressures.


In 76 the actual static c/r is less than 8 to 1 so short cam timing with a straight up timing set and a proper ignition curve is needed.




SJ
used 2b RHP


:D
 

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Discussion Starter #3
Ok, ill check all of that out then. Seems like having the high lift cam would cause lots of problems if your not doing the top end.....

next question, if you dont mind.

i have a line on a set of Dove's(ported/Polished), i was worried about compression being to high for regular gas. I thought it was on the high end of 8:1. Rumour has it those heads with the smaller chambers would raise me about a full point? Do you think i would have a problem of detonation? The reason this is relevant is i was looking at making this my project. And if i have to mess with valves/springs i may as well pull the heads and put some love into them ? Thank you in advance
 

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Ok, ill check all of that out then. Seems like having the high lift cam would cause lots of problems if your not doing the top end.....

next question, if you dont mind.

i have a line on a set of Dove's(ported/Polished), i was worried about compression being to high for regular gas. I thought it was on the high end of 8:1. Rumour has it those heads with the smaller chambers would raise me about a full point? Do you think i would have a problem of detonation? The reason this is relevant is i was looking at making this my project. And if i have to mess with valves/springs i may as well pull the heads and put some love into them ? Thank you in advance

Static c/r on a 76 oem 460 is in the high 7's. Adding small chamber heads might get you to 9 to 1.

How rattle happy the combo is will depend on cam timing, ignition curve, quench distance, intake manifold cross over heat, T stat temp, your location and altitude.

I used to have a low mileage 78 F250 CS. I put a pair of our budget early castings on the OEM short block. Pistons were only .020" in the hole at TDC. Custom Voodoo 213 / 227 cam, straight up timing set, properly curved DS distributor, performer intake and dual exhaust with oem truck manifolds.

Truck liked 89 octane as we are near sea level. Went from a turd to boiling the tires from a dead punch.


SJ
used 2b RHP


:D
 
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